2024/05/14 更新

ツボイ ノブユキ
坪井 伸幸
TSUBOI Nobuyuki
Scopus 論文情報  
総論文数: 0  総Citation: 0  h-index: 12

Citation Countは当該年に発表した論文の被引用数

所属
大学院工学研究院 機械知能工学研究系
職名
教授
メールアドレス
メールアドレス
研究室電話
093-884-3134
外部リンク

研究キーワード

  • ロケットエンジン

  • 超音速燃焼

  • 希薄流

  • 将来宇宙輸送機

  • デトネーション

取得学位

  • 東京大学  -  博士(工学)   2000年03月

学内職務経歴

  • 2013年05月 - 現在   九州工業大学   大学院工学研究院   機械知能工学研究系     教授

  • 2009年07月 - 2013年04月   九州工業大学   大学院工学研究院   機械知能工学研究系     准教授

論文

  • Investigation of liquid n-heptane/air spray detonation with an Eulerian-Eulerian model 査読有り 国際誌

    Jourdaine N., Tsuboi N., Hayashi A.K.

    Combustion and Flame   244   2022年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    A two-dimensional numerical simulation of detonation in a reactive dispersed liquid droplet cloud is performed with an Eulerian-Eulerian method. This study aims to investigate the model and the effects of two-phase sub-models on the propagation of a detonation through an n-heptane spray. Firstly, the simulations are compared to the experiments conducted in the thesis of Mohamed El-Amine Benmahammed [1]. Three simulations are carried out for a mono-dispersed/one sample cloud of droplets with a mass corresponding to equivalence ratios of 0.8, 1.0, and 1.3. The Eulerian-Eulerian method predicted the experimental detonation velocity and gaseous phase thermodynamic properties with reasonable accuracy. Secondly, an investigation of the effects of the mobilization of the droplet size poly-dispersity on the detonation properties was carried out. For a droplet Sauter mean diameter of 30 µm, the effect of the number of droplet samples used for modeling the poly-dispersity modifies the front structure and detonation properties. For instance, comparing 15 samples of droplet size to a unique sample, the detonation velocity decreases by 2.0 %, and the mean detonation cell width increases by 10 %.

    DOI: 10.1016/j.combustflame.2022.112278

    Scopus

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  • Effects of a Recess on Coaxial Cryogenic Injections at Supercritical Pressure 査読有り 国際誌

    Muto D., Terashima H., Araki T., Tsuboi N.

    Journal of Propulsion and Power   38 ( 4 )   581 - 591   2022年01月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Effects of recess lengths on coaxial cryogenic jets under a supercritical pressure are numerically studied. A hybrid large-eddy simulation/Reynolds-averaged Navier–Stokes methodology is applied to capture unsteady jet behaviors of recessed injectors. For the injector with a moderate recess length, the dense-core length of the inner jet is shorter than that with a nonrecessed injector, demonstrating that recessing improves the mixing. The flowfields show that the vortex structures in an inner mixing layer are strongly developed within the recessed region, and the entrainment of the outer jet into the inner jet is strengthened. However, a further increase in the recess length turns to the increase of the dense-core length and deteriorates the inner jet decay along the centerline. This deterioration is caused by the separation of the outer jet flow on the wall in the recessed region. The turbulence generation in the outer mixing layer is suppressed because of the separation, resulting in less enhancement of the mixing in the downstream region. Therefore, the study demonstrates that there is an approximate recess length for optimum jet mixing. Finally, a correlation relationship is provided between the dense-core length and the momentum flux ratio from a comprehensive comparison of existing experimental and numerical data.

    DOI: 10.2514/1.B38552

    Scopus

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  • Operation characteristics of a disk-type rotating detonation engine 査読有り 国際誌

    Ishii K., Ohno K., Kawana H., Kawasaki K., Hayashi A.K., Tsuboi N.

    Shock Waves   33 ( 3 )   267 - 274   2023年04月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    In the present work, operation characteristics of a disk-type rotating detonation engine (DRDE) with a constant chamber area were experimentally studied for various total mass flow rates and a wide variety of equivalence ratios of hydrogen–air mixtures. From the direct visualizations, the rotating detonation wave was found to propagate near the outer wall of the combustion chamber, regardless of the wave mode. For the present test conditions, single- and double-wave modes are observed, depending on the equivalence ratio of the mixture. The pressure gain was evaluated based on a one-dimensional flow model together with the chamber static pressure measured with the capillary tube average pressure technique. Although the present DRDE configuration provided a negative pressure gain for all the test conditions, it was found that the single-wave mode was superior to the double-wave mode in terms of the pressure gain.

    DOI: 10.1007/s00193-023-01133-6

    Scopus

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  • Influence of tube cross-section geometry on high-pressure hydrogen-flow-induced self-ignition 査読有り 国際誌

    Asahara M., Yokoyama A., Tsuboi N., Hayashi A.K.

    International Journal of Hydrogen Energy   48 ( 21 )   7909 - 7926   2023年03月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Self-ignition within a cylindrical tube that discharges high-pressure hydrogen results in flame formation. Because rectangular tubes are used to visualize fuel-flow dynamics, the influence of the tube cross-section on the self-ignition characteristics is investigated. As experimental investigation of the mechanisms underlying the self-ignition phenomenon in cylindrical tubes is difficult, three-dimensional numerical simulation is employed. Following the bursting of diaphragm by high-pressure hydrogen with a storage pressure of 9.0 MPa and a temperature of 300 K, initial self-ignition occurs at the center of the rectangular tube sidewall. This is because of the mixing of air and hydrogen induced by the bow-shock reflection-generated jet flow and resulting adiabatic shock compression-induced temperature increase. This temperature rise induces a secondary self-ignition at the tube corners. In the cylindrical tube, a solitary ring-shaped self-ignition occurs near the sidewall. The flame evolutions in rectangular and cylindrical tubes reveal similar flame-spreading trends, which indicates similar bow-shock reflection-induced self-ignition mechanisms.

    DOI: 10.1016/j.ijhydene.2022.08.210

    Scopus

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  • Validation of Soave–Redlich–Kwong equation of state coupled with a classical mixing rule for sound speed of non-ideal gas mixture of oxygen-hydrogen as liquid rocket propellants 査読有り 国際誌

    Takahashi R., Tsuboi N., Tokumasu T., Tsuda S.I.

    Journal of Thermal Science and Technology ( 一般社団法人日本機械学会・社団法人日本伝熱学会 )   18 ( 1 )   22-00365 - 22-00365   2023年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Numerical simulations of inlet jets flow of propellants in the main combustion chamber equipped in a liquid rocket engine have been conducted by compressible CFD technics employing a van der Waals-type equation of state (EOS) and chemical reaction models. Various simulations have been already conducted both for combustion and non-combustion state in the chamber; however, the accuracy of EOS for the mixture of propellant employing a classical mixing rule (CMR), particularly for the sound speed, has not been understood well. Therefore, we have validated the applicability of Soave–Redlich–Kwong (SRK) EOS as one of the van der Waals-type EOSs coupled with the CMR for the sound speed using molecular dynamics (MD) simulations against an imaginary model of oxygen-hydrogen mixture system. We found that SRK EOS coupled with a well-employed CMR can reproduce the sound speed in the MD simulations within a relative error of several percent and that the CMR hardly increases the deviation of the SRK EOS in the single component. The present results suggest that the SRK EOS with the CMR cannot be the main factor to cause critical errors in the CFD based on RANS, which will give reliability to current CFD simulations for internal flows in a combustion chamber of a liquid rocket engine.

    DOI: 10.1299/jtst.22-00365

    Scopus

    CiNii Research

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  • Numerical Study of Cryogenic Hydrogen Jet in Crossflow under Supercritical Pressure: Comparison of Tandem and Twin Jets 査読有り 国際誌

    NAKATSUKASA Tomohito, AMANO Taishi, ARAKI Takahide, TERASHIMA Hiroshi, TSUBOI Nobuyuki, OZAWA Kohei

    Journal of Evolving Space Activities ( 宇宙技術および科学の国際シンポジウム )   1 ( 0 )   n/a   2023年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    <p>The present study numerically investigates the flow fields of the twin- and tandem-jet in crossflow (JIC) under supercritical pressure. An ILES/RANS method is applied. In the present JIC, cryogenic hydrogen jets are vertically injected to warm temperature hydrogen crossflow through circular injector holes. The results show that the penetration of cryogenic jets into the crossflow is more enhanced with the tandem-jet than with the twin-jet. The higher jet penetration with the tandem jets is caused by a downstream jet behavior less influenced by the crossflow. Nevertheless, a mixedness analysis indicates that the mixing state at a downstream position is almost similar between the tandem and twin jets.<b><i> </i></b></p>

    DOI: 10.57350/jesa.29

    CiNii Research

  • Visualization of the physical destruction process of additive-manufactured regression sensor structures 査読有り 国際誌

    Ozawa Kohei, Neki Tomoya, Tsuboi Nobuyuki

    Science and Technology of Energetic Materials ( 一般社団法人 火薬学会 )   84 ( 2 )   24 - 31   2023年01月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Advanced closed-loop control of thrust and mixture ratio of hybrid rockets can be realized by combing a fuel mass flow rate control technique with a real-time fuel regression measurement. One of the promising techniques to realize real-time fuel regression measurement is the multi-material-additive-manufactured solid fuel with an integrated sensor probe structure. In this work, the destruction process of its regression sensor structure was visualized by the high-speed video from the top view of the sensor structure. The acquired high-speed video revealed the destruction process and its relationship with the time history of the voltage on the sensor structure. One of the findings is that unevenness or bumps of the rung form hot spots with strong emission, leading to the dropping-off and entrainment of the fragmented rung into the diffusion flame. Another important finding is that the destruction process of the rung starts before the rapid voltage increase, but it precedes the more intensive and frequent destruction. The post-processing of the sequential frames of the high-speed video successfully provided the observation of the fuel surface behind the diffusion flames. These reconstructed videos visualized the motions of the fragmented rung remaining on the fuel surface. The physical destruction process of the regression sensor structure revealed in this study can contribute to the improvement of the sensor structure design to avoid the unexpected off-nominal responses previously observed.

    DOI: 10.34571/stem.84.2_24

    CiNii Research

  • Numerical study on unsteady characteristics of high-pressure hydrogen jet ejected from a pinhole 査読有り

    Asahara M., Iwasa T., Tsuboi N., Hayashi A.K.

    International Journal of Hydrogen Energy   47 ( 74 )   31709 - 31728   2022年08月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    The aim of this study was to delineate the unsteady fluid dynamics of the high-pressure hydrogen jet to clarify the relationship between the forced ignition position and the flame development characteristics in a high-pressure hydrogen jet leaking from a pinhole. The Navier–Stokes equation for a compressible multi-component gas was used to simulate a high-pressure (82 MPa stagnation pressure) unsteady hydrogen jet ejected into the atmosphere through a pinhole (diameter = 0.2 mm). The results indicated that the flapping jet at the base of the jet formed a cloud of highly concentrated hydrogen that flowed downstream. A correlation was observed between the spatio-temporal distribution of hydrogen concentration and velocity was observed. The unsteady high-pressure hydrogen jet obtained by simulation will be used in subsequent studies focusing on flame development under forced ignition.

    DOI: 10.1016/j.ijhydene.2022.05.079

    Scopus

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  • Numerical Analysis on Ammonia / Hydrogen / Air Detonation Using Detailed Chemical Reaction Model 査読有り 国際誌

    G. Inoue, N. Tsuboi, K. Ozawa, A.K. Hayashi

    28th International Colloquium on the Dynamics of Explosions and Reactive systems   Paper 94   2022年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Operation Characteristics of a Disk-Type Rotating Detonation Engine 査読有り 国際誌

    K. Ishii, K. Ohno, H. Kawana, K. Kawasaki, A.K. Hayashi, N. Tsuboi

    28th International Colloquium on the Dynamics of Explosions and Reactive systems   Paper 203   2022年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Analysis on Pressure Gain of Rotating Detonation Engine Using H2-O2 Gases: Influence of Number of Injector 査読有り 国際誌

    A.K. Hayashi, K. Yoshidomi, K. Ozawa, N. Tsuboi, H. Kawashima

    28th International Colloquium on the Dynamics of Explosions and Reactive systems   Paper 218   2022年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Experimental and Numerical Study on Disc-RDE: Relation between Number of Detonation Wave and Pressure 査読有り 国際誌

    Koichi Hayashi A., Ohno K., Ishii K., Shimomura K., Tsuboi N., Ozawa K., Jourdaine N.H., Dzieminska E., Obara T., Maeda S., Mizukaki T.

    AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022   2022年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Disc-RDE is studied experimentally and numerically to figure out how single-wave mode and double-wave mode appear. From the measurement, we can pick up the better condition for the better pressure gain result. The experimental results are obtained that rotating detonation waves mainly propagate near the outer circumference of the combustion chamber. A transition of the wave number from single to double is found to exist at the equivalence ratio of 0.67 to 0.84. However, the normal transition of wave number is from double to single transition at the equivalence ratio of 1.45 and higher. Numerical work starts with a single-wave system to turn to double-wave system, then single-wave system back due to the ignition, bifurcation, and so on. Depending on the condition, a single-wave becomes a double-wave, which is confirmed at both the experiment and numerical analysis. The reduction of detonation velocity is confirmed at both experiment and numerical calculation up to 7 % when a single detonation becomes double one.

    DOI: 10.2514/6.2022-0837

    Scopus

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  • Numerical Simulation on Rotating Detonation Engine: Effect of Number of Injection Ports in Non-Premixed H2-O2 Gases 査読有り 国際誌

    Yoshidomi K., Kurita N., Ozawa K., Tsuboi N., Hayashi A.K., Kawashima H.

    AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022   2022年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    The effect of the number of injection ports in H2-O2 non-premixed gases on the performance of rotating detonation engine is estimated using two-dimensional numerical simulation with a detailed H2-O2 chemical reaction model. The differences in the instantaneous flow field, specific impulse, detonation velocity, and pressure gain are discussed among three configurations with the different numbers of injection ports. The detonation disappears for the 40-port configuration, while it continues to propagate stably for 60-and 80-port configurations. During the detonation propagation, the specific impulse has small, but significant difference depending on the number of injection ports. Detonation velocity is lower than the CJ velocity and its difference increases as the number of injection ports decreases. Pressure gain using oxygen has a maximum value of-0.084 at the 60-port configuration.

    DOI: 10.2514/6.2022-1112

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  • Numerical Simulation of Jet Mixing in Supersonic Crossflow: Effect of Jet Exit Geometry 査読有り 国際誌

    IWASA Toshihiro, TSUBOI Nobuyuki

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES ( 一般社団法人 日本航空宇宙学会 )   65 ( 4 )   172 - 184   2022年01月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    <p>Implicit large-eddy simulation/Reynolds-averaged Navier-Stokes hybrid simulation of sheet-like hydrogen jets in a supersonic crossflow are performed to investigate jet mixing, focusing on the difference in flow structures between sheet-like jets and round jets. The simulation is validated with a helium jet experiment in terms of the mean concentration. The numerical results showed good agreement with the experimental results. A characteristic of injection from the sheet-like jet exit is the spread of the windward jet toward the spanwise direction owing to the strong interaction with the freestream, while the leeward jet highly penetrated the freestream. In the investigation on jet mixing using different jet exit geometries, it was found that the sheet-like jet has a lower mixing efficiency compared with the round jet. The two mixing characteristics of the sheet-like jet are (i) a large jet cross-sectional area, and (ii) a weak turbulent mixing in the windward shear layer. As the effect of the momentum flux ratio on the jet mixing with sheet-like jet port, the mixing is enhanced with increasing the momentum flux ratio.</p>

    DOI: 10.2322/tjsass.65.172

    CiNii Research

  • Attempts of Time-Resolved Fuel Regression Measurements of an Altering-Swirling-Oxidizer-Flow-Type Hybrid Rocket Motor 査読有り 国際誌

    Ozawa K., Omiya K., Tsuboi N., Ishii K.

    AIAA AVIATION 2022 Forum   2022年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    This paper presents efforts to acquire the time-resolved fuel regression data of an Altering-Swirling-Oxidizer-Flow-Type (A-SOFT) hybrid rocket motor using polylactic acid (PLA)-based segmented solid fuels as well as the steady-state fuel regression behavior of the A-SOFT with PLA-based solid fuel. The sensing segments are manufactured by the multi-material Fused Filament Fabrication. They have a ladder-shaped resistor structure to detect the fuel regression in the form of rapid voltage changes caused by its rung destruction. Despite the successful firings of the motor, the verification of the temporally resolved fuel regression was imperfect. The destructions of the first and final rungs provided rapid voltage change, but the other rungs did not provide a rapid voltage change when they were expected to be broken according to the time-averaged regression rate of the segment. The major factors causing the unexpected sensor voltages can include chamber pressure and thermal environments in the motor because the sensor structure had not been tested under these conditions. The spatiotemporal-averaged fuel regression behavior was approximated by a fuel-mass-flux-based linear regression, reflecting the variety of filling rates in additive-manufactured solid fuels. The approximation agreed with the resultant fuel regression behavior, with the residual standard deviation of 2.97×10-2 mm/s. The segmentation of the solid fuels provided the ease of post-experimental measurements of axial distribution of regression rates.

    DOI: 10.2514/6.2022-3565

    Scopus

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  • Numerical Simulation of the Deflagration to Detonation Transition in a Tube with Repeated Obstacles: Experimental Scale Simulation Using the Artificial Thickened Flame Method 査読有り 国際誌

    N. Tsuboi, A.K. Hayashi, Y. Tamauchi, T. Kodama

    Transactions on Aerospace Research   4 ( 265 )   41 - 53   2021年12月

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.2478/tar-2021-0022

  • Numerical investigation of three deflagration-to-detonation transition conditions related to the velocity of the spontaneous reaction wave 査読有り

    Tang X., Dziemińska E., Hayashi A.K., Tsuboi N.

    International Journal of Hydrogen Energy   46 ( 75 )   37487 - 37501   2021年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    In this work, the deflagration-to-detonation transition (DDT) process in a tube filled with quiescent and stoichiometric hydrogen/oxygen mixture is numerically simulated by a detailed chemical reaction model together with a high-resolution adaptive mesh refinement (AMR) mesh system. Then the flow field is analyzed in detail. It is found that for the onset of detonation in a DDT process there are three essential conditions related to the velocity of the spontaneous reaction wave DSpRW. The first condition is that on a hot spot the DSpRW should be slower than the speed of the Chapman–Jouguet (CJ) detonation wave DCJ to make sure that a spontaneous shock wave could arise originating from the spontaneous reaction wave. The spontaneous shock wave and the spontaneous reaction wave have conspicuous positive correlation to accelerate the spontaneous reaction wave to be faster than the local sound speed, which is the second DDT condition. With this condition the spontaneous reaction wave could catch up with its associated spontaneous shock wave and implement a coupling of the gasdynamics and the chemical energy release. This process is in line with Lee's SWACER idea, while throughout the process the spontaneous reaction wave propagates mainly through the Zel'dovich's reactivity gradients mechanism. Meanwhile, the gas velocity Vg is also essential to maintain the above two conditions and the resultant velocity meets the relation ∥DSpRW+Vg∥≥DCJ, which is the third condition. Distinctly this settles the wave speed gap between deflagration and detonation. More importantly, gas velocity plays an important role especially for the pressure build-up. The most important expressive differences between CJ deflagration and CJ detonation are the gas velocities of both the reactants and products as well as the pressure build-up. When these three relations successfully trigger a DDT and get a detonation wave, they still hold in the resulting detonation wave. They are delicately inherited as the inherent characters of the (detonation) wave. Formerly they are preconditioning-sustaining in the DDT process, and now they become self-sustaining in the detonation wave. Besides, the important role of the progress ratio of the induction period ε is emphasized for a spontaneous propagation.

    DOI: 10.1016/j.ijhydene.2021.09.055

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  • Time-resolved fuel regression measurement function of a hybrid rocket solid fuel integrated by multi-material additive manufacturing 査読有り

    Ozawa K., Wang H.w., Yoshino T., Tsuboi N.

    Acta Astronautica   187   89 - 100   2021年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    The function of time-resolved fuel regression measurement is integrated into additively manufactured hybrid rocket fuels and conceptually demonstrated through the comparison with time-resolved optical fuel regression measurements during burns. This function is enabled by multi-material additive manufacturing of mainly thermoplastic solid fuels with a ladder-shaped resistor made of a conductive thermoplastic. This functionalization has many advantages, as indicated by its wide range of applicability, including solid fuel grains with emerging complex geometries, cost-effectiveness, ease of implementation, and minimal influence on the original propulsive performance and fuel regression behavior. Fuel regression is detected by a step change in the voltage applied to the ladder-shaped resistor, indicating the breakage of its top fuel surface rung during a burn. For ignited cases, all the rung breaks were detected, while the fuel regression was also optically measured using high-speed video. Errors were observed between the fuel regression time-histories measured using the two methods; however, most of these errors could be explained by the distribution of the fuel regression in the camera direction and the camera resolution and the melted fuel layer thickness. Considering these uncertainties, the remaining errors that could not be explained by these factors were less than ±0.15 mm, corresponding to ±1 layer of additive manufacturing applied to the prototyping of the solid fuels.

    DOI: 10.1016/j.actaastro.2021.06.031

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  • Experimental and numerical study on disc-rde: Flow structure and its performances 査読有り

    Hayashi A.K., Ishii K., Watanabe T., Tsuboi N., Ozawa K., Jourdaine N.H., Dzieminska E., Tang X., Obara T., Maeda S., Mizukaki T.

    AIAA Scitech 2021 Forum   1 PartF   1 - 12   2021年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    The present study discusses disc-type rotating detonation engine (DRDE) experimentally and numerically. The experimental work shows that the detonation propagates in three different modes; single, dual, and hybrid. The operating frequency of dual-wave mode is 1.8-2.1 times faster than that of single wave mode. The number of detonation wave can be predicted based on the pressure history and the operating frequency signal. The numerical work shows the performance of 3D numerical analysis of DRDE with uniform injection case and multiport injection case. By increasing the wave number from one to two, the detonation propagation velocity decreases by 18.7 %. The one-detonation head case gives some better performance to the flow than the two-detonation head case. The inlet flow angle to the radial turbine becomes about 50 degrees to the radial direction no matter how large the plenum chamber is.

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  • ワックス燃料後退速度の加速度環境下における可視化システム研究開発

    長坂 春花, 小澤 晃平, 坪井 伸幸, 中田 大将

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2021 ( 0 )   2021年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2021.74.F33

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/130008092382

  • Regression behavior of polylactic acid manufactured by fused filament fabrication for hybrid rocket propulsion 査読有り 国際誌

    Ozawa Kohei, Wang Han-wei, Inenaga Takefumi, Tsuboi Nobuyuki

    Science and Technology of Energetic Materials ( 一般社団法人 火薬学会 )   82 ( 6 )   170 - 177   2021年01月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Advanced closed-loop control of thrust and mixture ratio of hybrid rockets is planned by combing a fuel mass flow rate control technique with a real-time fuel regression measurement. The latter technique is enabled by a multi-materialadditive-manufactured solid fuel with an integrated sensor probe structure. This work investigated the fuel regression behavior of polylactic acid (PLA) fuel used for the main material of this type of solid fuels. Rectangular slab fuels and cylindrical fuel grains were manufactured by Fused Filament Fabrication (FFF) and fired in an optically accessible slab burner and a lab-scale motor, respectively. The cylindrical fuel grains had more than 2 times larger regression rates than rectangular slab fuels even with the same PLA filament. One of the main factors causing this large difference can be an anisotropy in the fuel regression rate behavior of the solid fuels manufactured by FFF.

    DOI: 10.34571/stem.82.6_170

    CiNii Article

    CiNii Research

    その他リンク: http://hdl.handle.net/10228/00008705

  • 3D numerical study on flow field in disc-RDE 査読有り 国際誌

    Hayashi A.K., Shimomura K., Tsuboi N., Ozawa K., Jourdaine N.H., Ishii K., Dzieminska E., Obara T., Maeda S., Mizukaki T.

    AIAA Propulsion and Energy Forum, 2021   2021年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Disc-type rotating detonation engine is studied numerically using the threedimensional compressible Navier-Stokes equations with 9 species and 21 reactions and with an multi-port injection system. Especially the grid resolution using two-detonation case and the process of stabilization for one and two-detonation cases are studied. As the results of grid resolution, the case of larger grid number provides higher pressure due to capturing the pressure oscilation better and that their rotating speed becomes faster. And the detonation velocity becomes faster when the number of grid becomes larger. As the results of the process of stabilization for one and two-detonation cases, two detonation wave propagate by changing back and forth their distance and no matter what the number of detonation wave is given, one or two, the final detonation wave number becomes two.

    DOI: 10.2514/6.2021-3665

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85123365877&origin=inward

  • Numerical simulations on propane/oxygen detonation in a narrow channel using a detailed chemical mechanism: formation and detailed structure of irregular cells 査読有り 国際誌

    Takeshima N., Ozawa K., Tsuboi N., Hayashi A.K., Morii Y.

    Shock Waves   30 ( 7-8 )   809 - 824   2020年11月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Numerical simulations of two-dimensional inviscid detonations for a stoichiometric propane/oxygen gas mixture are performed using a detailed chemical reaction model. The UC San Diego model which includes 57 chemical species and 268 elementary reactions is mainly used in the present study. It is shown that a grid size of 3 µm can capture important features such as the unburned gas pocket behind the detonation when compared to larger grid sizes. The effects of channel width show that the detonation propagates with the CJ (Chapman–Jouguet) velocity for all cases and for more than 100 times the channel width of 4.5 mm. Increasing the channel width results in an irregular detonation cell structure. A transverse detonation forms with cross-hatching marks on the maximum pressure history. The irregular detonation cell structure forms because both the reduced activation energy and the stability parameter have a value of approximately 10; however, the maximum thermicity in the detonation is one. The free radicals C3H7 and H2O2 play an important role in the propane oxidation under the high temperature in the detonation. The maximum concentration exists at a temperature of 2000–3000 K. The fifth-order WCNS (weighted compact nonlinear scheme) scheme can resolve the contact surface and complicated flow structure behind the detonation front compared to the second-order MUSCL (Monotonic Upstream-centered Scheme for Conservation Laws).

    DOI: 10.1007/s00193-020-00978-5

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85097766750&origin=inward

  • Recent Experimental and Numerical Study on Disc-Type RDEs 査読有り 国際誌

    A. K. Hayashi, N. Tsuboi, K. Ozawa, T. Watanabe, N.H. Jordaine, K. Ishii, H. Kawana, W. Kuwata, K. Ohno, T. Obara, S. Maeda, E. Dzieminska, X. Tang, T. Mizukaki

    2020 AIAA SciTech   AIAA-2020-1169   2020年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    USA   Orlando  

  • Numerical Simulation on Disk Rotating Detonation Engine: Influence of Internal Flow Field Structure on Performance 査読有り 国際誌

    Tomohiro Watanabe, Kodai Shimomura, Nicolas H. Jourdaine, Kohei Ozawa, Nobuyuki Tsuboi, Takayuki Kojima, Kazuhiro Ishii, A. Koichi Hayashi

    AIAA Scitech 2020 Forum   AIAA-2020-2160   2020年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    USA   Orlando  

  • Three-Dimensional Numerical Simulation on Hydrogen/Air Rotating Detonation Engine with Aerospike Nozzle: Effects of Nozzle Geometries 査読有り 国際誌

    Nobuhiro Kurita, Nicolas Jourdaine, Nobuyuki Tsuboi, Kohei Ozawa, A. Koichi Hayashi

    2020 AIAA SciTech   AIAA-2020-0688   2020年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    USA   Orlando  

  • Accuracy of real-time fuel regression measurement function of a 3d printed solid fuel 査読有り

    Ozawa K., Wang H.W., Inenaga T., Tsuboi N.

    AIAA Propulsion and Energy 2020 Forum   1 - 15   2020年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    The accuracy of a real-time fuel regression measurement by an additive manufactured solid fuel was discussed by comparing with optically measured regression acquired in firing experiments for the conceptual demonstration. The solid fuels that succeeded in fuel regression measurement were manufactured by a multi-material 3D printer and had the ladder-shaped resistor structure with the 0.15 mm thickness rungs. The fuel regression is detected by the voltage change in the reference resistor due to the break of rungs. For all experiments, the initial resistance of the ladder-shaped resistor structure was estimated to be as expected, and all rung break was successfully detected by the steep voltage change. The acquired measurement values by the two methods had errors like an offset for all runs. The major factors of these errors were the distribution of the fuel regression in the fuel width direction and the resolution of the high-speed video camera. As a result, it was found that the time histories of the values optically measured for comparison had relatively large uncertainties. The remaining errors that cannot be explained by these major error factors were estimated to be less than ±0.15 mm, which corresponds to two layers of the solid fuels manufactured in this study.

    DOI: 10.2514/6.2020-3741

    Scopus

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  • 多素材3Dプリンタ製燃料後退計測機能付き固体燃料の研究

    小澤 晃平, 王 瀚緯, 坪井 伸幸

    スペース・エンジニアリング・コンファレンス講演論文集 ( 一般社団法人 日本機械学会 )   2020 ( 0 )   2020年01月

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    記述言語:英語   掲載種別:研究論文(研究会,シンポジウム資料等)

    <p>Prototype solid fuels for a hybrid rocket were fabricated by using a multi-material 3D printer and conductive thermoplastic composite to construct a ladder-shaped resistance inside the electrically-insulated thermoplastic solid fuel and to measure the time-resolved fuel regression. In this type of fuels, the remaining fuel thickness is monitored by the voltage applied to the resistance that changes according to the number of rungs of the ladder-shaped resistor. For comparison with the proposed measurement, the time-resolved fuel regression was optically measured by using a high-speed video visualization. The solid fuel regression history with the proposed technique agreed well with that with the optical measurement considering the uncertainties in the measurement methods. Errors that cannot be explained by these uncertainties were found to be ±0.15 [mm], corresponding to ±1 layer of the stacking pitch of the 3D printer applied in this study. This paper also shows a preliminary firing test result using a post-processed 3D-printed cylindrical solid fuel grain as a preparation for the application of the proposed technique to the cylindrical solid fuel.</p>

    DOI: 10.1299/jsmesec.2020.29.C1

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/130008064623

  • Three-dimensional numerical simulation on hydrogen/air rotating detonation engine with aerospike nozzle: Effects of nozzle geometries 査読有り

    Kurita N., Jourdaine N., Tsuboi N., Ozawa K., Hayashi A.K., Kojima T.

    AIAA Scitech 2020 Forum   1 PartF   2020年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Three-dimensional simulations with a detailed chemical reaction model were performed to evaluate the propulsive performance of rotating detonation engines (RDEs) for H2/Air with conic aerospike nozzles. The simulations aimed to clarify the propulsive performance for various configurations of aerospike nozzle: open/choked or complete/truncated configurations. The governing equations were the Euler equations, and the chemical model was for 9 species and 21 element chemical reactions. Various equivalent ratios from 0.9 to 1.4 were simulated. The results show that the specific impulse (Isp) and the efficiency of the choked nozzle were 4-6% higher than those for the open nozzle. The higher pressure in the chamber due to the decreasing in the throat area resulted in a gain of pressure thrust by the nozzle and consequently, an addition in Isp and the efficiency. The difference in thrust performance between the complete and the truncated nozzle was smaller than 2% because the pressure component on the base surface compensated for the thrust drop.

    DOI: 10.2514/6.2020-0688

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85091953963&origin=inward

  • Recent experimental and numerical study on disc-type rdes 査読有り

    Hayashi K., Tsuboi N., Ozawa K., Watanabe T., Jourdaine N.H., Ishii K., Kawana H., Kuwata W., Ohno K., Obara T., Maeda S., Dzieminska E., Tang X., Mizukaki T.

    AIAA Scitech 2020 Forum   1 PartF   2020年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    The present study discusses disc-type rotating detonation engine (DTRDE) experimental ly and numerically. The experimental work is performed using hydrogen and air and measuring pressure records together with taking a high speed movie to see a direction of rotating detonation. Especially the relation between mass flow rate and operation frequency and that between equivalence ratio and operation frequency. The number of detonation head is figured out from the maximum operation frequency. Then the 3D numerical analysis of DTRDE will provide the flow structure in the DTRDE combustion chamber, high pressure profile, and low mach number profiles.

    DOI: 10.2514/6.2020-1169

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85091925389&origin=inward

  • Numerical study on JP-10/air detonation and rotating detonation engine 査読有り 国際誌

    Hayashi A.K., Tsuboi N., Dzieminska E.

    AIAA Journal   58 ( 12 )   5078 - 5094   2020年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    JP-10/air two-phase detonation and rotating detonation engine (RDE) are numerically studied to find out their limits of physical values as a function of equivalence ratio, prevaporization, fuel concentration, droplet diameter, and initial pressure and temperature. To find such limits, the JP-10/air two-step chemical reaction mechanism is used and the Eulerian–Eulerian two-phase governing system is developed to simulate those limits. Especially the JP-10/air two-phase detonation velocity and cell size are investigated in detail and the generation of nonreacted region and quenching mechanism of JP-10/air two-phase RDE are simulated. The findings from those studies are that 1) the JP-10/air two-phase detonation and RDE codes are developed and validated to calculate detonation and RDE; 2) the JP-10/air detonation cell size is calculated by the developed code to show a good agreement with the experimental data; and 3) the JP-10/air RDE simulation shows a detonation quenching at the condition when the droplet diameter is larger than 4 μm and the prevaporization factor is smaller than 20%.

    DOI: 10.2514/1.J058167

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85092899280&origin=inward

  • Real-time regression rate measurement of an additive-manufactured functional hybrid rocket fuel 査読有り 国際誌

    Ozawa, K, Wang, H.-W., Yoshino, T., Tsuboi, N.

    70th International Astronautical Congress, IAC 2019   2019年10月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    USA   Washington  

  • Boundary-layer combustion of wax-based fuels at various chamber pressures under two static acceleration environments 査読有り 国際誌

    Ozawa, K., Yoshino, T., Wang, H.-W., Tsuboi, N.

    AIAA Propulsion and Energy Forum and Exposition 2019   AIAA-2019-4100   2019年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    USA   Indianapolis  

    DOI: 10.2514/6.2019-4100.c1

  • A Study on Operating Conditions of Disk-Type Rotating Detonation Engine 査読有り 国際誌

    H. Kawana, W. Kurata, K. Ohno, K. Ishii, A. K. Hayashi, N. Tsuboi, K. Ozawa, T. Obara, S. Maeda, E. Dzieminska, T. Mizukaki

    27th International Colloquium on the Dynamics of Explosions and Reactive System   415   2019年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    China   Beijing  

  • Gradient Mechanism on the Onset of Detonation in the Deflagration to Detonation Transition 査読有り 国際誌

    X. M. Tang, E. Dzieminska, A.K. Hayashi, N. Tsuboi

    27th International Colloquium on the Dynamics of Explosions and Reactive System   247   2019年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    China   Beijing  

  • Simulation of detonation propagation in a two-phase gas/liquid cross flow injection 査読有り 国際誌

    Nicolas Jourdaine, Nobuyuki Tsuboi, A. Koichi Hayashi, Xinmeng Tang, Kohei Ozawa

    27th International Colloquium on the Dynamics of Explosions and Reactive System   435   2019年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    China   Beijing  

  • Two-dimensional Numerical Simulations on Unstable Propagation of Propane/Oxygen Detonation Using Detailed Chemical Mechanism 査読有り 国際誌

    Naomi Takeshima, Kohei Ozawa, Nobuyuki Tsuboi, Youhi Morii, A. Koichi Hayashi

    27th International Colloquium on the Dynamics of Explosions and Reactive System   268   2019年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    China   Beijing  

  • Two-dimensional Numerical Simulation of Flame Acceleration and Deflagration-to-Detonation Transition in Channels with Obstacles: Effects of Blockage Ratio and Channel Size 査読有り 国際誌

    Kanta Iwasaki, Ayu Ago, Nobuyuki Tsuboi, Kohei Ozawa, A. Koichi Hayashi

    27th International Colloquium on the Dynamics of Explosions and Reactive System   267   2019年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    China   Beijing  

  • Mixing characteristics of the slit-shaped hydrogen jet in supersonic crossflow 査読有り 国際誌

    Toshihiro Iwasa, Nobuyuki Tsuboi

    32nd International Symposium on Shock Waves   OR-21-0357   2019年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Singapore   Singapore  

  • Feasibility Study of a Real-time Fuel Regression Rate Measurement using an Electrostatic Capacitive Probe for Hybrid Rocket Engine 査読有り

    Han-Wei Wang, Kohei Ozawa, Nobuyuki Tsuboi

    32nd International Symposium on Space Technology and Science 2019   a91363   2019年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Study on Cryogenic Jet/Crossflow Interaction Structures under a Supercritical Pressure 査読有り

    Taishi Amano, Takahide Araki, Hiroshi Terashima, Daiki Muto, Kohei Ozawa, Nobuyuki Tsuboi

    32nd International Symposium on Space Technology and Science (ISTS)   a91387   2019年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Validation of classical mixing rule coupled with van der Waals type equation of state for sound speed of non-ideal gas mixture

    Ryuji Takahashi, Nobuyuki Tsuboi, Takashi Tokumasu, Satoshi Watanabe and Shin-ichi Tsuda

    American Physical Society March Meeting 2019   R18.00010   2019年03月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Three-dimensional numerical thrust performance analysis of hydrogen fuel mixture rotating detonation engine with aerospike nozzle 査読有り

    Jourdaine N., Tsuboi N., Ozawa K., Kojima T., Koichi Hayashi A.

    Proceedings of the Combustion Institute   37 ( 3 )   3443 - 3451   2019年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    The propulsive performance for an H 2 /O 2 and H 2 /Air rotating detonation engine (RDE) with conic aerospike nozzle has been estimated using three-dimensional numerical simulation with detailed chemical reaction model. The present paper provides the evaluation of the specific impulse (I sp ), pressure gain and the thrust coefficient for different micro-nozzle stagnation pressures and for two configurations of conic aerospike nozzle, open and choked aerospike. The simulations show that regardless of the nozzle, increase the micro-nozzles stagnation pressure increases the mass flow rate, the pre-detonation gases pressure and consequently the post-detonation pressure. This gain of pressure in the combustion chamber leads to a higher pressure thrust through the nozzle, improving the I sp . It was also found that the choked nozzle increases the chamber time-averaged static pressure by 50-60% compared with the open nozzle, inducing higher performance for the same reason explained before.

    DOI: 10.1016/j.proci.2018.09.024

    Scopus

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  • Three-dimensional numerical simulation of disk rotating detonation engine: Unsteady flow structure 査読有り

    Watanabe T., Jourdaine N., Ozawa K., Tsuboi N., Kojima T., Hayashi A.

    AIAA Scitech 2019 Forum   2019年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2019 by Timothy K. Minton. Published by the American Institute of Aeronautics and Astronautics, Inc. Disk Rotating Detonation Engine (DRDE) simulation using a mixture of hydrogen and oxygen was performed by three-dimensional numerical analysis with detailed chemical reaction model. The computational grid is created based on the DRDE combustor shape designed by Huff et al. and this grid system use three regions. In zone 1 and 2, the inside of the combustor is simulated and in zone 3, the flow behind the nozzle exit is simulated. The combination of coarse and fine computational grids can calculate the propagation of rotating detonation wave inside the DRDE with small computational resources. The present results show that the detonation wave front is not normal to the outer circular wall but has approximately 60 degrees. The maximum pressure near the detonation head on the outer wall has approximately 10 MPa. The Mach number of the exhaust flow becomes approximately 2.5 in this condition.

    DOI: 10.2514/6.2019-1498

    Scopus

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  • Development of a high efficiency system with a rotating detonation engine for a gas turbine engine (RDE-GTE) using pressure gain combustion 査読有り

    Koichi Hayashi A., Tsuboi N., Ozawa K., Ishii K., Obara T., Maeda S., Dzieminska E., Mizukaki T.

    AIAA Scitech 2019 Forum   2019年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2019 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. The present study will show a new development of a gasturbine engine with rotating detonation engine. Five universities and a venture company will study characteristics of rotating detonation engines to develop a gasturbine engine with RDE system in order to improve its performance of gas turbine engine, especially its efficiency. We have three teams; the experimental team, numerical team, and gasturbine team. The experimental team will perform several categories; concentric as well as disk type RDE development and measurement of its stable conditions and controlabilities as well as its efficiency; the cooling system of RDE; injection and ignition system; and DDT performance. The numerical group will simulate above experimental categories by real size calculations with both DNS and AMR base. And a micro-gasturbine engine will be run together with RDE system in a near future. We prefer to choose a disc type RDE instead of concentric cylinder type one. Hence the midterm report like presentation will be given at the SciTech meeting, Jan 2019 and 2020.

    DOI: 10.2514/6.2019-1509

    Scopus

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  • Effects of a recess on supercritical co-flowing planar jets 査読有り

    Muto D., Terashima H., Tsuboi N.

    Transactions of the Japan Society for Aeronautical and Space Sciences   62 ( 4 )   203 - 212   2019年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2019 The Japan Society for Aeronautical and Space Sciences. The effects of a recess on co-flowing planar jets under supercritical pressure are numerically studied. Two-dimensional hybrid LES/RANS simulations are performed in a wide range of recess lengths and injection momentum flux ratios, which are important design parameters for liquid rocket engine injectors. The present study showed that confinement effects of the near-injector flowfield by applying a recess, suppress outer jet spreading and thus enhances the penetration of the outer jet flow into the inner jet. The enhanced penetration of the outer jet flow results in the appearance of flapping motions in the inner jet. Low-frequency oscillations corresponding to the flapping motions clearly appear in the case of recessed injectors. Moreover, the confinement effects promote interactions between vortex structures resulting in vortex breakdown. Consequently, the inner-jet length is shortened, indicating an improvement in mixing when a recess is applied. The present results also show that the inner-jet length deceases as the recess length increases, and the effects of a recess remarkably appear at higher momentum flux ratios. This is explained by the vortices generated behind the post lip that is strengthened as the result of increased velocity ratio.

    DOI: 10.2322/tjsass.62.203

    Scopus

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  • 障害物を有する管内での酸水素デトネーション遷移の2次元数値解析:実験との比較

    岩﨑 幹太, 吾郷 愛由, 坪井 伸幸, 小澤 晃平, 林 光一

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2019 ( 0 )   2019年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    <p>Detonation is a type of premixed combustion, which propagates interacting with shock waves and combustion flames at supersonic speed. It is known in the early researches that DDT (Deflagration to Detonation Transition) in a channel is promoted by installing obstacles. This research investigates flame propagation and local explosions in channels filled with hydrogen/oxygen stoichiometric mixture and installed ten obstacles by using the two-dimensional simulation with a detailed reaction model. Furthermore, we estimate differences between the three-dimensional experiments performed in a past study and the present two-dimensional simulations. The simulations performed by changing the scale of the channel, grid width, and obstacle height. As a result, the flames did not transit to detonation under any conditions of the obstacle heights and channel sizes, unlike the experiments. Higher obstacles disturbed the flame propagation and induced the shock waves crossing the channel, which lead to the enhancement and acceleration of the combustion reaction. A small local explosion was observed near the eighth obstacle at one-tenth the size. The flame acceleration was faster in the experiment than in the numerical analysis.</p>

    DOI: 10.1299/jsmekyushu.2019.72.B14

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/130007801915

  • 超臨界圧下における主流と直交干渉する極低温噴流構造について:3-D LES/RANSハイブリッド解析

    天野 泰嗣, 荒木 天秀, 寺島 洋史, 武藤 大貴, 坪井 伸幸

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2019 ( 0 )   2019年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    <p>The engine cycle of a Japanese next flagship liquid rocket applies an expander bleed cycle and it has a component called mixer. In the mixer, cryogenic hydrogen is vertically injected through the perforated plate into the high temperature hydrogen flow under supercritical pressures. It is important to complete mixing efficiently in the mixer because insufficient mixing may lead to non-uniform temperature distribution and thereby cause combustion instabilities in the chamber. The objective of this study is to investigate flow structures and mixing of a cryogenic jet injected into the crossflow under a supercritical pressure using a three-dimensional LES/RANS hybrid model. The results found that periodic vortex structures are formed around the jet and they have dominant role on near jet mixing processes. The shedding vortices penetrate into a region behind the jet, establishing a recirculation region. There are some differences in the jet height and the recirculation region, compared with those in a two-dimensional calculation.</p>

    DOI: 10.1299/jsmekyushu.2019.72.D12

    CiNii Article

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  • 異種分子間相互作用の影響に注目した酸水素混合系に対するcubic型状態方程式の第一原理的検証

    髙橋 竜二, 坪井 伸幸, 徳増 崇, 渡邉 聡, 津田 伸一

    年次大会 ( 一般社団法人 日本機械学会 )   2019 ( 0 )   2019年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    <p>In compressible computational fluid dynamics (CFD) analyses for combustion chamber of liquid rocket engine, the combination of cubic type equation of state (EOS) and classical mixing rule (CMR) is mostly used as typical EOS for mixture system. However, validation of the EOS for the mixture of liquid rocket propellant has hardly been validated due to lack of experimental data. Previously, validation of cubic type EOS with CMR was conducted by molecular simulation applying an <i>ab-initio</i> intermolecular potential as a quantum chemical approach. However, the accuracy of the H<sub>2</sub>-O<sub>2</sub> potential is questionable because it was constructed on the basis of molecular orbital (MO) calculation for some limited molecular orientations. Therefore, in this study, we performed MO calculations for more molecular orientations between H<sub>2</sub>-O<sub>2</sub> and reconstructed the intermolecular potential on the basis of the results of MO calculations with CCSD(T)/augcc-PVQZ level of theory. Next, we revalidated cubic type EOS coupled with CMR by evaluating the thermophysical properties of supercritical oxygen-hydrogen mixture system using Monte Carlo (MC) simulations applying the improved H<sub>2</sub>-O<sub>2</sub> potential. As a result, we confirmed that cubic type EOS coupled with CMR can roughly reproduce the thermophysical properties obtained from MC simulation. Therefore, it was suggested that cubic type EOS with CMR can be applied to CFD analyses for combustion chamber of liquid rocket engine.</p>

    DOI: 10.1299/jsmemecj.2019.J05412

    CiNii Article

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  • メタン/酸素予混合気におけるデトネーションセル構造の新たな可視化方法とギャッロッピングデトネーションの速度振動の詳細計測に関する研究

    久門 昂平, 小澤 晃平, 坪井 伸幸, 林 光一

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2019 ( 0 )   2019年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    <p>In order to understand the detailed mechanism of galloping detonation of methane and oxygen, efforts were made to improve the cellular structure and propagation velocity of unsteady detonation. Firstly, as an alternative to smoked foil method, a new visualization of cell structure was attempted using CB film, mylar film covered by carbon black with spray-type adhesive. CB film succeeded in recording cell structure, and this result suggests a potential to apply for image recognition of the cell structure using strong backlight at scanning CB film. Secondly, the correlation between the cell structure and the propagation velocity in a galloping detonation was investigated by combining the detonation velocity measurement and smoked foil method. The propagation velocity distribution was measured using twice the sampling points in the same detonation tube length as in our previous research. This experiment revealed that, after the over-driven detonation started to decelerate, small non-uniform cell structure was formed and transited to spinning mode during the deceleration. Consequently, in galloping detonation, a strong correlation was found between wave-front acceleration and cell structure.</p>

    DOI: 10.1299/jsmekyushu.2019.72.D13

    CiNii Article

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  • Real-time regression rate measurement of an additive-manufactured functional hybrid rocket fuel 査読有り

    Ozawa K., Wang H.W., Yoshino T., Tsuboi N.

    Proceedings of the International Astronautical Congress, IAC   2019-October   2019年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Copyright © 2019 by the International Astronautical Federation (IAF). All rights reserved. The function of real-time fuel regression integrated into an additively-manufactured hybrid rocket fuel was conceptually demonstrated by firing experiments. This fuel has a complex ladder resistor structure made of a plastic filament including conductive additives in an electrically insulated main plastic fuel. The real-time regression rate measurement is enabled by the change of the voltage applied to the ladder resistor structure when the top rung is broken by the fuel regression. This type of fuel has advantages in the easy acquisition of the distribution of the local regression rates with a greatly small pitch, minimizing the influences on the structural mass, propulsive performance, and fuel regression behavior especially when loading such a measurement system on space vehicles. Prototype slab fuels outputted steep changes in the voltage indicating the break of the rungs when using rungs with the thickness of 0.15 mm in firing experiments. The acquired breaking signals with the positions of the rungs were compared with the results of the fuel surface detection in the high-speed videos. In 3 of 4 successful experiments, the sensing system of the proposing measurement method followed the fuel regression detected by the high-speed videos within 0.5 mm errors, which are in the same range as the roughness of the solid fuels after the burns. The time history of the breaking signals showed a fuel regression at an almost constant rate. The difference of the steady-state regression rates was less than 0.06 mm/s between these two methods, except for run #4, 0.094 mm/s. It was also confirmed that the ladder resistor structures can be a heater to warm the main solid fuel when applying a voltage larger than 5 V to the resistor structure. This function is also useful for the thermal management of solid fuels in space.

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  • Boundary-layer combustion of wax-based fuels at various chamber pressures under two static acceleration environments 査読有り

    Ozawa K., Yoshino T., Wang H.W., Tsuboi N.

    AIAA Propulsion and Energy Forum and Exposition, 2019   2019年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2019 by American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved. Boundary layer combustion of wax-based fuels was visualized under atmospheric and supercritical chamber pressures under vertical and horizontal setups. The final goal of this research is to clarify the effects of acceleration environments on the performance of wax-based fuels. At the atmospheric pressure, the roll waves of the melted fuel excited propagated over the fuel top surface, and fuel droplets were entrained by the main gaseous flow for the horizontal setup. However the propagation of the roll waves covered at most 55% of the fuel to surface, and the entrained fuel droplets were hardly observed for the vertical setup. Above the critical pressure, the instabilities of the melted fuel were observed for both setups, but it was difficult to find any differences in the behaviors of the melted fuel due to the strong radiation of the fuel-rich flame on the melted fuels even after the various improvements of the optical system and the solid fuel. At supercritical pressures, the diffusion flames and the melted fuels oscillated at the frequency of approximately 600 Hz by sight, which is approximately the same with the natural frequency of the TCG coupling mode. The fast Fourier transformation up to 500 Hz output an intense peak of approximately 311 Hz for all runs with the horizontal setup and the sonic nozzle. A slight difference in the fuel regression behavior was found between the two burner setups. The vertically set burner showed the larger regression rates at supercritical conditions whereas the regression exponent for the horizontal setup agreed with that of existing data with a horizontally set motor. This result suggests body force increases the mass flow rate of the melted fuel film, which was not considered as a fuel mass transfer in the current liquefying hybrid theory.

    DOI: 10.2514/6.2019-4100

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  • Numerical Study on Aerodynamic Characteristics of Reusable Vehicle-eXperiment Rocket with Body-flap during Gliding

    Yoshiki Nishikawa, Nobuyuki Tsuboi, Takashi Ito, Satoshi Nonaka

    15th International Conference on Flow Dynamics   GS1-30   2018年11月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Statistical mechanical evaluation of thermophysical properties of oxygen-hydrogen mixture system based on the differential hierarchy of a complete thermodynamic function

    Ryuji Takahashi, Nobuyuki Tsuboi, Takashi Tokumasu and Shin-ichi Tsuda

    Fifteenth International Conference on Flow Dynamics   CRF-58   2018年11月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Simulations of Hydrogen Jet Mixing in Supersonic Crossflow for Liquid Rocket Commanded Destruction

    Toshihiro Iwasa, Keiichiro Fujimoto, Daiki Muto, Nobuyuki Tsuboi

    12th Asian Computational Fluid Dynamics Conference   0104   2018年10月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Two-Dimensional Numerical Simulation of Detonation Transition with Multi-Step Reaction Model: Effects of Obstacle Height 査読有り

    A. Ago, N. Tsuboi, E. Dzieminska, A. K. Hayashi

    Combustion Science and Technology   191   659 - 675   2018年08月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1080/00102202.2018.1498849

  • Numerical investigation of a high pressure hydrogen jet of 82 MPa with adaptive mesh refinement: Concentration and velocity distributions 査読有り

    Tang X., Dzieminska E., Asahara M., Hayashi A., Tsuboi N.

    International Journal of Hydrogen Energy   43 ( 18 )   9094 - 9109   2018年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2018 Hydrogen Energy Publications LLC To investigate the safety properties of high-pressure hydrogen discharge or leakage, an under-expanded hydrogen jet flow with a storage pressure of 82 MPa from a small jet orifice with a diameter of 0.2 mm is studied by three-dimensional (3D) numerical calculations. The full 3D compressible Navier-Stokes equations are utilized in a domain with a size of about 3 × 3 × 6 m which is discretized by employing an adaptive mesh refinement (AMR) technology to reduce the number of grid cells. By AMR, the local mesh resolutions can narrowly cover the Taylor microscale lTand direct numerical simulations (DNS) are performed. Both the instantaneous and mean hydrogen concentration distributions in the present jet are discussed. The instantaneous concentrations of hydrogen CH2on the axis presents significant turbulent pulsating oscillations. The centerline value of the intensity of concentration fluctuation σˆH2asymptotically comes to 0.23, which is in a good agreement with the existing experimental results. It substantiates the conclusion that the asymptotic centerline value of σˆH2is independent of jet density ratio. The probability distributions function (PDF) of instantaneous axial CH2agree approximately with the Gaussian distribution while skewing a little to the higher range. The time averaged hydrogen concentration C¯H2along the radial directions can also be described as a Gaussian distribution. The axial C¯H2of 82 MPa hydrogen jet tends to obey the distribution discipline approximated with C¯H2=4200/(z/θ) where z is the axial distance from the nozzle and θ is the effective ejection diameter, which is consistent with the experimental results. In addition, the hydrogen tip penetration Ztipis found to be in a linear relationship with the square root of jet flow time t. Meanwhile, the jet's velocity half-width LVhapproximately gains an linear relation with z which can be expressed as LVh=0.09z.

    DOI: 10.1016/j.ijhydene.2018.03.089

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  • Three-dimensional numerical simulation on hydrogen-oxygen rotating detonation engine with unchoked aerospike nozzle 査読有り

    Tsuboi N., Jourdaine N., Watanabe T., Koichi Hayashi A., Kojima T.

    AIAA Aerospace Sciences Meeting, 2018   ( 210059 )   2018年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved. The present study simulates three-dimensional rotating detonation engine with an unchoked aerospike nozzle geometry for hydrogen/oxygen gas mixture to understand the advantages to use the aerospike nozzle on the thrust performance. The gonverning equations uses the unsteady three-dimensional compressible Euler equations with the detailed chemistry model. The oblique shock wave propagates along the coaxial combustion chamber and outside of the nozzle exit. The exhaust jet under atmospheric condition is slightly underexpanded and some complicated and unsteady shock waves are formed in the plume. The degree of the expansion in the exaust flow increases as the stagnation pressure increases. The effects of the stagnation pressure on the thrust performance indicate that Isp increases 270s for p0= 4 MPa although Isp for p0= 1.5 MPa is 220s. The time-averaged thrust is proportional to the injected mass flow and this feature is different from those without the external regions.

    DOI: 10.2514/6.2018-1885

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  • Visualization of boundary layer combustion of wax-based fuels in vertical and horizontal configurations 査読有り

    Ozawa K., Yoshino T., Tsuboi N.

    2018 Joint Propulsion Conference   2018年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved. Efforts have been carried out from both the theoretical and experimental approaches to reveal the effects of body force parallel to the main flow on the diffusion flame in hybrid rocket propulsion with entrainment of liquid fuel droplets. A theoretical study on liquefying fuels such as wax fuels were partially extended for static acceleration environments and acquired interesting results that the static body force scarcely affects the internal ballistics of the entrained fuel droplets but it can affect the thickness of the liquid fuel layer and the fuel regression rate of the entrained droplets. Diffusion flame of two wax fuels at the atmospheric pressure has been visualized with a slab burner and a high-speed camera in the horizontally and vertical configurations to change the body force loaded to the fluid in the slab burner. The instability of the diffusion flames looked similar to each other over all the experiments, and the high-speed video has observed a few burning droplets entrained from the liquid fuel layer in each of the experiments. The monitoring camera observed a lot of unburned fuel droplets from the slab burner vertically installed.

    DOI: 10.2514/6.2018-4928

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  • Validation of classical mixing rule coupled with a van der Waals-type equation of state for supercritical mixture system of oxygen and hydrogen using molecular simulation 査読有り

    TAKAHASHI Ryuji, TSUBOI Nobuyuki, TOKUMASU Takashi, TSUDA Shin-ichi

    Mechanical Engineering Letters   2018年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1299/mel.18-00369

  • Numerical prediction of forced-ignition limit in high-pressurized hydrogen jet flow through a pinhole 査読有り

    Makoto Asahara, Nobuyuki Tsuboi, N., Fujimoto, K., Muto, D., Hayashi, A.K.

    Intermational Conference on Hydrogen Safety   ID193   2017年09月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • A molecular dynamics study of nuclear quantum effect on diffusivity of hydrogen molecule 査読有り

    Nagashima H., Tsuda S., Tsuboi N., Hayashi A., Tokumasu T.

    Journal of Chemical Physics   147 ( 2 )   2017年07月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2017 Author(s). In this paper, the nuclear quantum effect of the hydrogen molecule on its diffusivity was analyzed using the molecular dynamics (MD) method. The centroid MD (CMD) method was applied to reproduce the time evolution of the molecules. The diffusion coefficient of hydrogen was calculated using the Green-Kubo method over a wide temperature region, and the temperature dependence of the quantum effect of the hydrogen molecule on its diffusivity was addressed. The calculated results were compared with classical MD results based on the principle of corresponding state (PCS). It was confirmed that the difference in the diffusion coefficient calculated in the CMD and classical MD methods was small, and the PCS appears to be satisfied on the temperature dependence of the diffusion coefficient, even though the quantum effect of the hydrogen molecules was taken into account. It was clarified that this result did not suggest that the quantum effect on the diffusivity of the hydrogen molecule was small but that the two changes in the intermolecular interaction of hydrogen due to the quantum effect offset each other. Moreover, it was found that this tendency was related to the temperature dependence of the ratio of the kinetic energy of the quantum fluctuational motion to the classical kinetic energy.

    DOI: 10.1063/1.4991732

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  • Numerical Study on Effects of Obstacle Shape on Detonation Transition Mechanism 査読有り

    A. Ago, T. Niibo, N. Tsuboi, A.K. Hayashi

    26th International Colloquium on the Dynamics of Explosions and Reactive systems   1027   2017年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Analysis on Liquid JP10 Rotating Detonation Engine 査読有り

    A.K. Hayashi, W. Yoshida, M. Asahara, N. Tsuboi

    26th International Colloquium on the Dynamics of Explosions and Reactive systems   2017年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Two-Dimensional Numerical Analysis on Shock Flame Interaction in Premixed Gas of Hydrocarbon/Oxygen with Multi-Step Reaction Model 査読有り

    M. Iwai, K. Yoshida, Y. Morii, N. Tsuboi, A.K. Hayashi

    26th International Colloquium on the Dynamics of Explosions and Reactive systems   1050   2017年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Experimental Study on Behavior of Methane/Oxygen Gas Detonation Near Propagation Limit in Small Diameter Tube: Effects of Equivalent Ratio 査読有り

    K. Yoshida, T. Inoue, Y. Morii, K. Murakami, N. Tsuboi, A.K. Hayashi,

    26th International Colloquium on the Dynamics of Explosions and Reactive systems   822   2017年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Simulations of Transverse Jet in Supersonic Crossflow toward an Understanding of Interaction Mechanism 査読有り

    Toshihiro Iwasa, Keiichiro Fujimoto, Daiki Muto, Nobuyuki Tsuboi

    31st International Symposium Shock Waves   2017年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical investigation of a high pressure hydrogen jet of 82 MPa with adaptive mesh refinement: The starting transient evolution and Mach disk stabilization 査読有り

    Tang X., Asahara M., Hayashi A., Tsuboi N.

    International Journal of Hydrogen Energy   42 ( 10 )   7120 - 7134   2017年03月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2017A three-dimensional (3D) strongly under expanded hydrogen jet flow is numerically investigated with a storage pressure of 82 MPa and a tiny jet orifice diameter of 0.2 mm. The full compressible Navier–Stokes equations are utilized in a domain with a size of about 3 × 3 × 6 m which is discretized by employing adaptive mesh refinement (AMR) technology to reduce the number of grid cells. The highly under expanded hydrogen jet flow with a nozzle pressure ratio (NPR) of about 809 is then captured from the very beginning when hydrogen is ejected out of the jet orifice. The starting transient evolution and Mach disk stabilization are then discussed in details. It is found that with the AMR technology, the grid number can be greatly reduced and high resolutions can be easily installed to deal with the small jet orifice size together with those flow microscales. Jet flow is numerically captured and discussed. It is found that over expansion occurs in this under expanded jet. The secondary shock is generated to match the pressure which plays the most important physics in the starting transient period of an under expanded hydrogen jet. The Mach shock and the lateral barrel shock which are originated from the secondary shock play central roles. The jet flow is divided into subsonic and supersonic branches in the near-nozzle region, which makes the highly under-expanded jets have two annular shear layers, the inner and outer layer, in this region.

    DOI: 10.1016/j.ijhydene.2017.01.016

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  • Three-dimensional numerical simulation on dispersion process of unsteady high pressure hydrogen jet flow 査読有り

    Tsuboi N., Fujimoto K., Muto D., Asahara M., Hayashi A.

    AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting   2017年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2017 by the authors.The numerical simulations on the high-pressure hydrogen jet are performed by using the unsteady three-dimensional compressible Navier-Stokes equations with multi-species conservation equations. The present numerical results show that the highly expanded hydrogen free jet observes and the distance between the Mach disc and the nozzle exit agrees well with the empirical equation. The time-averaged H2 concentration of the numerical simulations agrees well with the experimental data and the empirical equation. The unsteady feature in the present numerical simulation shows that the PDF of the numerical simulations does not agree with the Gaussian PDF because the jet flow is “potential core” flow at x = 60 mm. Although higher hydrogen concentration is observed at x = 120 mm, the PDF in the numerical simulations agrees well with the Gaussian PDF at x = 180 mm. The numerical simulation of ignition in hydrogen jet is performed to show that the calculated OH distribution becomes isotropic expansion in the initial stage; however, OH flows along the leeward direction.

    DOI: 10.2514/6.2017-1232

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  • Numerical simulation for effects of pressure on cryogenic coaxial jet under supercritical pressure 査読有り

    Araki T., Muto D., Terashima H., Tsuboi N.

    AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting   2017年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2017 by Rolls-Royce North America Holdings Inc.Three-dimensional numerical simulations of coaxial nitrogen jet mixing under supercritical pressures are performed with an emphasis on the effects of pressure on the mixing. The results show that the overall mixing behaviors are similar in terms of normalized density profiles between 5 and 12 MPa. However, the normalized temperature profiles are different between two conditions because non-linear change of the density to the temperature near the critical point. The peak of the constant pressure specific heat is particularly observed in the case of 5 MPa. The density and temperature fluctuations become large between the inner jet flow and the outer jet flow. Although the density fluctuation distributions are similar between two cases, the larger fluctuation region of temperature is observed in the case of 5 MPa. This is because the temperature increases are different near the critical temperature between two pressure conditions.

    DOI: 10.2514/6.2017-1108

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  • Front cellular structure and thrust performance on hydrogen-oxygen rotating detonation engine 査読有り

    Tsuboi N., Eto S., Hayashi A., Kojima T.

    Journal of Propulsion and Power   33 ( 1 )   100 - 111   2017年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Copyright © 2016 by the authors.Numerical simulations of three-dimensional rotating detonation engines for a hydrogen-oxygen mixture are performed using the detailed chemistry model. The grid-resolution study indicates that the cellular structure of the detonation appears near the inner wall as the circumferential grid resolution increases. However, the effects of the grid resolution are small on Isp. The grid resolution for the high-mass-flow cases should be carefully considered because the rotating detonation velocity increases to produce higher thrust under the low grid resolution. As the annular width increases, a complicated shock structure such as a Mach stem appears, and the cycle time decreases. The effects of the annular width are smallon Isp. As the number of the rotating detonations increases, the asymmetric detonation heads rotate along the circumferential direction with the same cycle time after 30 cycles. Isp for the two-waved rotating detonation engine decreases approximately 10% less than Isp for the one-waved rotating detonation engine. This is because the injected mixture mass flow rate for the two-waved rotating detonation engine increases 16% larger than that for the one-waved rotating detonation engine, whereas the thrusts between them coincide.

    DOI: 10.2514/1.B36095

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  • Three-Dimensional Numerical Simulation of a Rotating Detonation Engine: Effects of the Throat of a Converging-Diverging Nozzle on Engine Performance 査読有り

    Eto S., Tsuboi N., Takayuki K., Hayashi A.

    Combustion Science and Technology   188 ( 11-12 )   2105 - 2116   2016年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2016 Taylor & Francis.The effect of a converging-diverging nozzle on the performance of a rotating detonation engine was estimated using three-dimensional numerical simulations with a detailed chemical reaction model. The nozzle in this article is composed of a long constant cross section, a short converging section, and a diverging section. The expansion area ratios of nozzles A and B in this article are 2.0 and 1.89, respectively. The periodic exhaust oscillation due to rotating detonation is considerably reduced by nozzle A. The variation of the time-averaged pressure is approximately 0.0048 MPa and the ratio to the time-averaged value is 1.3%. For nozzle B, the variation in pressure is approximately 0.018 MPa, and the ratio to the time-averaged value is 5%. The specific impulse of nozzle A increases by approximately 11 s (3.8%) compared with the value of nozzle B.

    DOI: 10.1080/00102202.2016.1213990

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84992752898&origin=inward

  • Study on Behavior of Methane/Oxygen Gas Detonation Near Propagation Limit in Small Diameter Tube: Effect of Tube Diameter 査読有り

    Yoshida K., Hayashi K., Morii Y., Murakami K., Tsuboi N., Hayashi A.

    Combustion Science and Technology   188 ( 11-12 )   2012 - 2025   2016年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2016 Taylor & Francis.The unstable behavior of the detonation is an important issue in predicting detonation limits and safety problems. The present study aims to obtain information of the unstable behavior near the detonation propagating limit in methane/oxygen gas mixture for various initial pressures and tube diameters. The detonation velocity rapidly decreases near α = 1.0 and deviates from the theoretical value for α < 1.0 conditions (α = πd/λ; d: tube diameter; λ: cell width). The onset of the single-head spinning is α = 1.0. For α < 1.0 conditions, the transition to the single-head spinning from small cells and the failure of cellular patterns were observed. For α > 1.0 conditions, the propagation mode was unstable. The unstable phenomenon means that the cellular pattern repeats multi-head and single-head spinning in turn.

    DOI: 10.1080/00102202.2016.1213989

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84992702450&origin=inward

  • Numerical Study on Direct Initiation of Cylindrical Detonation in H<inf>2</inf>/O<inf>2</inf> Mixtures: Effect of Higher-Order Schemes on Detonation Propagation 査読有り

    Niibo T., Morii Y., Ashahara M., Tsuboi N., Hayashi A.

    Combustion Science and Technology   188 ( 11-12 )   2044 - 2059   2016年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2016 Taylor & Francis.This aim of this study is to investigate the effect of grid resolution and higher-order accuracy schemes. The size of the reaction induction zone at the time of the local explosion affects the generation of transverse cells. When the reaction zone is large, transverse cells appear. As a result, for calculations in which the grid width is small or for a higher-order scheme, such as a weighted compact nonlinear scheme (WCNS), is used, the cell size increases; an irregular cellular structure is obtained, such as that observed in experiments; and unburned gas pockets and circulation structures caused by Kelvin–Helmholtz instability appear behind the detonation front. In terms of the computational cost, the computational time of 7th-order WCNS is approximately three times that of the 2nd-order monotone upstream-centered schemes for conservation laws (MUSCL) scheme.

    DOI: 10.1080/00102202.2016.1215109

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84992730237&origin=inward

  • D-08 液体燃料ロケットタンク破壊時の推進剤ジェット・主流の干渉構造に関する数値解析

    岩佐 聡洋, 武藤 大貴, 藤本 圭一郎, 坪井 伸幸

    日本機械学会九州支部講演論文集   2016 ( 69 )   141 - 142   2016年03月

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    記述言語:日本語   掲載種別:研究論文(その他学術会議資料等)

    CiNii Article

    その他リンク: http://ci.nii.ac.jp/naid/110010054693

  • E-23 分子シミュレーションを用いた超臨界混合系における古典的混合則の精度検証

    谷口 正興, 津田 伸一, 坪井 伸幸

    日本機械学会九州支部講演論文集   2016 ( 69 )   215 - 216   2016年03月

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    記述言語:日本語   掲載種別:研究論文(その他学術会議資料等)

    CiNii Article

    その他リンク: http://ci.nii.ac.jp/naid/110010054730

  • Numerical Analyses on Ethylene/Oxygen Detonation with Multi-step Chemical Reaction Mechanisms: Grid Resolution and Chemical Reaction Model 査読有り

    Takayuki Araki, Keisuke Yoshida, Youhi Morii, Nobuyuki Tsuboi, A. Koichi Hayashi

    Combustion Science and Technology   188 ( 3 )   346 - 369   2016年03月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1080/00102202.2015.1106484

    Scopus

  • Numerical simulation of the effects of nozzle on thrust performance of rotating detonation engine 査読有り

    Eto S., Watanabe Y., Tsuboi N., Kojima T., Hayashi A.

    Science and Technology of Energetic Materials   77 ( 5-6 )   122 - 127   2016年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    The effects of the converging-diverging (CD) nozzle on the thrust performance of the rotating detonation engine (RDE) were estimated by using the three-dimensional numerical simulations with the detailed chemical reaction model. The nozzle geometry is based on the reference of Rankin et al. The nozzle is composed of the long constant cross section, the short converging section, and the diverging section. The periodic exhaust oscillation is considerably reduced by the present CD nozzle. The pressure difference from the averaged value is approximately 1.2 % and the difference in Mach number is approximately 0.4 %. The increment of Isp using the CD nozzle is approximately 15 s. The nozzle performance is estimated via the thrust coefficient. The thrust coefficient of the CD nozzle used this study is nearly corresponded with the ideal value. The combustion efficiency of C∗ ηc∗ are obtained 92-98 % between the combustion chamber pressure of 1.2 and 2.9 MPa.

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85015674567&origin=inward

  • Numerical simulation of jet mixing in a recessed coaxial injector at supercritical pressure 査読有り

    Muto D., Terashima H., Tsuboi N.

    54th AIAA Aerospace Sciences Meeting   2016年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.Three-dimensional numerical simulations of cryogenic coaxial jets under supercritical pressure are performed with flushed and recessed injectors to investigate the effect of a recess on the coaxial mixing. A hybrid ILES/RANS method is applied to simulate wallbounded injectors and a recessed region. The recessed injector enhances the density decay and the temperature increase on the central axis, indicating the improvement of mixing compared with the flushed injector. However, the mixing improvement by the recess is not significant in the present conditions. The recess also induces distinct vortex rings around the outer jet. The power spectra of the velocity fluctuations also demonstrated that the low-frequency velocity fluctuations are clearly induced by the recess which frequency corresponds to the large vortex structures.

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85007569638&origin=inward

  • 自由回転軸を持つ翼型を用いた円柱の抗力低減方法について 査読有り

    佐藤 一志, 吹場 活佳, 坪井 伸幸

    日本航空宇宙学会論文集   64 ( 3 )   153 - 159   2016年01月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

    A novel drag reduction method for a cylinder using a pivoted airfoil is proposed in this study. The pivoted airfoil can rotate freely on a shaft so that the airfoil can head windward. First, we conducted a water tunnel test to validate the drag reduction method. Contrary to our expectation, the airfoil did not head windward completely. The airfoil started to move from an initial angle of 0º to a stable angle of about 14º. Next, we calculated the aerodynamic force of the airfoil by a computational fluid dynamics (CFD) method. The reason the airfoil did not head windward completely was revealed. This is because the sign of the moment coefficient around the rotating shaft changes with increasing angle of attack. The CFD simulation also revealed that the drag reduction method can decrease the drag by 34%.

    DOI: 10.2322/jjsass.64.153

    CiNii Article

    その他リンク: http://ci.nii.ac.jp/naid/130005154803

  • Characteristics of Jet-Mixing at Supercritical Pressure: Effects of Recess Length and Post Height 査読有り

    MUTO Daiki, TERASHIMA Hiroshi, TSUBOI Nobuyuki

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN   14 ( 30 )   Pa_45 - Pa_52   2016年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    <p>Effects of injector geometries on cryogenic co-flowing planar jets under a supercritical pressure are numerically investigated. The present study covers a wide range of injector exit geometries which focuses post lip height and recess length, and evaluates these effects on mixing characteristics. A hybrid ILES/RANS methodology is applied to simulate wall-bounded injector regions. The results show that thicker post lips generate larger vortices behind the post lip, resulting the comb-like structure of the rolled-up inner dense jet. As a result, the mixing is well improved, and the inner jet potential core is shortened. The recessed injectors additionally induce a large-scale flapping motion of the inner jet and further enhance the mixing. The frequency analysis with velocity fluctuations demonstrates that the vortex shedding behind the post lip has a frequency which depends on the post lip height. The recessed injectors induce another low-frequency peak of the flapping motion, and which value is independent of the post lip height.</p>

    DOI: 10.2322/tastj.14.Pa_45

    CiNii Article

    その他リンク: http://ci.nii.ac.jp/naid/130005172064

  • 極低温超臨界圧下の噴流に関する流体力学とその数値解析

    坪井伸幸

    日本燃焼学会誌 ( 日本燃焼学会 )   57 ( 182 )   257 - 264   2015年11月

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    担当区分:責任著者   記述言語:日本語   掲載種別:記事・総説・解説・論説等(学術雑誌)

  • D121 管内高圧水素噴流による自着火機構(OS-10:火災・爆発(2))

    朝原 誠, 横山 瑛紀, 窪田 智之, 佐分利 禎, 和田 有司, 茂木 俊夫, 坪井 伸幸

    熱工学コンファレンス講演論文集   2015   "D121 - 1"-"D121-2"   2015年10月

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    記述言語:日本語   掲載種別:研究論文(その他学術会議資料等)

    This paper deals with a self-ignition mechanism of high-pressure hydrogen jet in a tube filled with air. Although the self-ignition phenomenon is expected to clarify for industrial safety, the ignition mechanism in a tube still has not been known well. In this study, the direct photographs of flame behaver initiated by the self-ignition are captured by a high speed camera. The flame propagation histories are obtained from the pressure and light sensors. Additionally, a numerical simulation is performed to understand the ignition process induced by hydrogen jet in detail. As the results, a self-ignition occurs at the region where the contact surface interacts with the local high-temperature region which is built by the shock wave reflects from the sidewall of tube.

    CiNii Article

    その他リンク: http://ci.nii.ac.jp/naid/110010045446

  • Numerical simulation on low-speed hydrogen jet diffusion 査読有り

    Yuki Takatori, Nobuyuki Tsuboi, Keisuke Fujimoto, Daiki Muto, Makoto Asahara

    The 6th International Conference on Hydrogen Safety   ID179   2015年10月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • J0540307 二原子分子流体の臨界点近傍における静的・動的ゆらぎ構造の分子動力学的解析

    井川 祥平, 永島 浩樹, 坪井 伸幸, 徳増 崇, 津田 伸一

    年次大会 : Mechanical Engineering Congress, Japan   2015   "J0540307 - 1"-"J0540307-5"   2015年09月

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    記述言語:日本語   掲載種別:研究論文(その他学術会議資料等)

    In our study, we investigated fluctuation structure of diatomic fluids around the critical point. We used molecular dynamics simulation to evaluate the principle of corresponding state of fluctuation structure of 2-center-Lennard-Jones fluid which has molecular elongation as a parameter. We evaluated the static fluctuation structure by calculating dispersion of number of molecules at divided cells and static structure factor. As results, the principle of corresponding state on the static fluctuation structure is satisfied because static fluctuation structure does not have dependence on molecular elongation. On the other hand, dynamic fluctuation structure of fluid which has longer molecular elongation disagrees with dynamic fluctuation structure of fluid which has shorter molecular elongation. Therefore, it was found that the principle of corresponding state of dynamic fluctuation structure might not be satisfied.

    CiNii Article

    その他リンク: http://ci.nii.ac.jp/naid/110010048952

  • Three-dimensional cellular structure and propagation process of spherical detonation 査読有り

    R. Iida, M. Asahara, A. Hayashi, N. Tsuboi

    25th International Colloquium on the Dynamics of Explosions and Reactive Systems   No.273   2015年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Behavior of Methane/Oxygen Gas Detonation near Propagating Limit in Small Diameter Tube:Effect of Tube Diameter 査読有り

    K. Yoshida, K. Hayashi, Y. Morii, K. Murakami, A. Susa, N. Tsuboi, A. Hayashi

    25th International Colloquium on the Dynamics of Explosions and Reactive Systems   No.139   2015年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • 3D Numerical Simulation on Rotating Detonation Engine: Effects of Converging-Diverging-Nozzle on Thrust Performance 査読有り

    Seiichiro ETO, Yusuke WATANABE, Nobuyuki TSUBOI, Takayuki KOJIMA, A. Koichi HAYASHI

    25th International Colloquium on the Dynamics of Explosions and Reactive Systems   No.132   2015年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Study on Direct of Cylindrical Detonation in H2/O2 Mixture: Influence of Higher-order Scheme 査読有り

    Tomotaka NIIBO, Youhi MORII, Nobuyuki TSUBOI, Makoto ASAHARA, A. Koichi HAYASHI

    25th International Colloquium on the Dynamics of Explosions and Reactive Systems   No.136   2015年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • デフラグレーションからデトネーションへの遷移過程における新展開 -音速近傍で伝播する火炎の存在-

    朝原誠,坪井伸幸,石井一洋,林光一

    Explosion ( 日本火薬学会 )   25 ( 1 )   16 - 21   2015年04月

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    記述言語:日本語   掲載種別:記事・総説・解説・論説等(学術雑誌)

  • 円筒デトネーションの伝播過程とセル構造に関する数値解析 査読有り

    朝原誠,飯田遼平,林光一,坪井伸幸

    Explosion   25 ( 1 )   8 - 15   2015年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Extraction of the Density Fluctuations in Diatomic Fluids Around the Critical Points Using Molecular Dynamics Simulation 査読有り

    Shin-ichi Tsuda, Masato Tomi, Nobuyuki Tsuboi, Shohei Ikawa, and Takashi Tokumasu

    Journal of Nanoscience and Nanotechnology   15 ( 4 )   3117 - 3120   2015年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1166/jnn.2015.9623

    Scopus

  • Numerical simulation of propagation process and cellular structure of cylindrical detonation 査読有り

    Asahara M., Iida R., Hayashi A., Tsuboi N.

    Explosion   25 ( 1 )   8 - 15   2015年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84937033379&origin=inward

  • New page of deflagration to detonation transition - Flame propagation around a speed of sound 査読有り

    Asahara M., Tsuboi N., Ishii K., Hayashi A.

    Explosion   25 ( 1 )   16 - 21   2015年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84937029644&origin=inward

  • Reactive fluid Dynamics laboratory Department of Mechanical and Control Engineering, Faculty of Engineering, Kyushu Institute of Technology

    Tsuboi N.

    Explosion ( Explosion )   25 ( 3 )   198 - 199   2015年01月

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    記述言語:日本語   掲載種別:記事・総説・解説・論説等(学術雑誌)

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84969524528&origin=inward

  • Three-Dimensional Simulation on Deflagration-to-Detonation Transition with a Detailed Chemical Reaction Model 査読有り

    Takuya Machida, Makoto Asahara, A. Koichi Hayashi, Nobuyuki Tsuboi

    Combustion Science and Technology   186 ( 10-11 )   1758 - 1773   2014年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1080/00102202.2014.935647

    Scopus

  • Implementation of Weighted Compact Nonlinear Scheme for Hydrogen/Air Detonation 査読有り

    Ryohei Iida, Makoto Asahara, A. Koichi Hayashi, Nobuyuki Tsuboi, Taku Nonomura

    Combustion Science and Technology   186 ( 10-11 )   1736 - 1757   2014年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1080/00102202.2014.935646

    Scopus

  • Aerodynamic Characteristics of Simplified Waveriders 査読有り

    Haruka Etoh, Nobuyuki Tsuboi, Yusuke Maru, Kazuhisa Fujita

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN   12 ( ists29 )   Pg_25 - Pg_31   2014年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    CiNii Article

  • Numerical simulation of auto-ignition induced by high-pressure hydrogen release with detailed reaction model: Fluid dynamic effect by diaphragm shape and boundary layer 査読有り

    M.Asahara, A. Yokoyama, A.Koichi Hayashi, E. Yamada, N. Tsuboi

    International Journal of Hydrogen Energy   39   20378 - 20387   2014年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1016/j.ijhydene.2014.05.136

    Scopus

  • Numerical Study of Real Gas Effects on Shock Tube Problems 査読有り

    Daiki Muto, Hiroshi Terashima, Nobuyuki Tsuboi

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN   12 ( ists29 )   Po_2_39 - Po_2_44   2014年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Estimation of the Thrust Performance on a Rotating Detonation Engine for a Hydrogen-Oxygen Mixture 査読有り

    Nobuyuki Tsuboi, Yusuke Watanabe, Takayuki Kojima, and A.Koichi Hayashi

    Proceedings of the Combustion Institute, The Combustion Institute   35   2005 - 2013   2014年11月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1016/j.proci.2014.09.010

    Scopus

  • Spinning detonation , cross-currents, and the Chapman-Jouguet velocity 査読有り

    M. Kurosaka, N. Tsuboi

    Journal of Fluid Mechanics   756   728 - 757   2014年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1017/jfm.2014.460

    Scopus

  • 二原子分子流体の臨界点近傍におけるゆらぎ構造の分子動力学計算 査読有り

    冨正人,井川祥平,坪井伸幸,徳増崇,津田伸一

    日本機械学会論文集   80 ( 816 )   TEP0231   2014年08月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1299/transjsme.2014tep0231

  • Effect of pressure-dependent detailed chemical reaction models on detonation cell size 査読有り

    Koji Yamashita, Makoto Asahara, Koichi Hayashi, N. Tsuboi

    Tenth International Symposium in Hazards, Preventation, and Mitigatikon of Industrial Explosion (X ISHPMIE)   #65   2014年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Multi-dimensional propagation process of diverging detonation 査読有り

    Ryohei Iida, Makoto Asahara, Nobuyuki Tsuboi, Koichi Hayashi

    Tenth International Symposium in Hazards, Preventation, and Mitigatikon of Industrial Explosion (X ISHPMIE)   #64   2014年06月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • 直接起爆による酸水素爆轟波の爆轟限界近傍における数値解析 査読有り

    朝原 誠,林 光一,坪井 伸幸

    Science and Technology of Energetic Materials   75 ( 4 )   99 - 105   2014年05月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • An Analysis of Quantum Effects on the Thermodynamic Properties of Cryogenic Hydrogen Using the Path Integral Method 査読有り

    Hiroki Nagashima, Shin-ichi Tsuda, Nobuyuki Tsuboi,A. Koichi Hayashi, and Takasih Tokumasu

    THE JOURNAL OF CHEMICAL PHYSICS   134506-1-10   2014年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.4870036

    Scopus

  • Numerical study of cryogenic coaxial jet under supercritical condition 査読有り

    Muto D., Tsuboi N., Terashima H.

    52nd Aerospace Sciences Meeting   2014年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2014, American Institute of Aeronautics and Astronautics Inc. All rights reserved.Effects of recess on the mixing of the cryogenic coaxial jet under supercritical conditions were numerically investigated. Recessed injectors have been applied as coaxial injectors of liquid rocket engines because it is expected to improve propellant mixing and combustion efficiency. In the present study, a numerical simulation code was developed to examine jet mixing under the supercritical pressures. For validation of the present method, a two-dimensional planner jet simulation was carried out. The present result showed good agreement with an experimental result. As a preliminary study of coaxial jets, co-planner simulations were performed in a recessed case and an unrecessed case. Large-scale vortical structures were observed in the both cases, and the recessed case showed the larger struc- tures relative to the unrecessed case. This is because of the destabilization mechanism of a recessed region. These instabilities improved entrainments of ambient uid, and as a result, the enhanced jet mixing shortens the jet-core length.

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84938403091&origin=inward

  • Numerical simulation on ignition with shock tube - Effect of reflected shock wave - Boundary layer at adiabatic wall interaction on ignition 査読有り

    Asahara M., Machida T., Yamada E., Hayashi A., Tsuboi N.

    Science and Technology of Energetic Materials   75 ( 1-2 )   50 - 58   2014年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    A reflected shock wave in two-dimensional shock tube is studied numerically using Navier-Stokes equations with the detailed oxy-hydrogen reaction mechanism. The results reproduced mild and strong ignition behind the reflected shock wave, in particular, the detailed mild ignition process, which was not shown well in past research. Owing to the interaction between the viscous boundary layer and the reflected shock wave, the latter has a lambda shock configuration. The flow behind the lambda shock wave becomes a complex vortical structure ; thus, the reactive gas mixture flowing along the detached vortices reaches high temperature and pressure because of compression at the tube side walls. The chemical reaction starts at the location that reaches the auto-ignition temperature to create flame kernels. The above history is appropriate for the process in which a flame kernel appears at the location between the triple point of the lambda shock wave and the tube wall but is insufficient for the process in which a flame kernel appears near the tube center, which is above the triple point of the lambda shock wave.

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84904443456&origin=inward

  • Numerical simulation on H<inf>2</inf>-O<inf>2</inf> detonation induced by direct initiation near detonation limits 査読有り

    Asahara M., Hayashi A., Tsuboi N.

    Science and Technology of Energetic Materials   75 ( 3-4 )   99 - 105   2014年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    In order to prevent an accidental explosion by detonation it is necessary to clarify detonation limit and to comprehend its ignition condition. In the past experimental studies were performed to understand critical initiation energy and critical energy density and to propose detonation limit by initiation energy and energy density. However extracting dominant parameters for detonation continuation is difficult because various experimental conditions to compare for detonation continuation are not definitely consistent Therefore these parameters will be put in order by numerically analyzing 2D direct initiation of detonation in oxyhydrogen mixture assuming ideal ignition conditions, and will be clarified for detonation limits. As a result it is found that there exist the conditions for detonation and explosion. These conditions are organized to obtain a detonation limit curve which is quite similar curve shown by Watt and Sharpe. The obtained detonation limit curve is found to be a function of a radius and pressure of initial source region and to give a prediction of the critical source energy for detonation with those initial conditions Additionally a local explosion is predicted near the x-axis boundary under a quasi-steady state condition because of a disturbance there and this type of local explosion was observed by Bach et aL.

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84916939418&origin=inward

  • An analysis of the quantum effect on the thermodynamic and transport properties of cryogenic hydrogen using molecular dynamics method 査読有り

    Nagashima H., Tsuda S., Tsuboi N., Koshi M., Hayashi A., Tokumasu T.

    Journal of Physics: Conference Series   490 ( 1 )   2014年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    In this paper, we have analysed an effect of quantum nature of the hydrogen molecule on its thermodynamic and transport properties using molecular dynamics (MD) method based on the path integral method. We performed NVE constant MD simulation and the quantum effect on the molecular mechanism was analysed. The simulation results were compared with experimental data. As a result, we clarified that the quantum nature makes the virial pressure larger than in classical mechanics and taking account the quantum nature makes smaller intermolecular interaction energy and larger repulsive force than classical representation. Besides, we have confirmed that the path-integral-based MD method well reproduces the thermal conductivity and quantum effect on the transport properties is also large. © Published under licence by IOP Publishing Ltd.

    DOI: 10.1088/1742-6596/490/1/012160

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84896979582&origin=inward

  • A molecular dynamics study of nuclear quantum effect on the diffusion of hydrogen in condensed phase 査読有り

    Nagashima H., Tsuda S., Tsuboi N., Koshi M., Hayashie A., Tokumasu T.

    AIP Conference Proceedings   1618   950 - 953   2014年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    © 2014 AIP Publishing LLC.In this paper, the quantum effect of hydrogen molecule on its diffusivity is analyzed using Molecular Dynamics (MD) method. The path integral centroid MD (CMD) method is applied for the reproduction method of time evolution of the molecules. The diffusion coefficient of liquid hydrogen is calculated using the Green-Kubo method. The simulation is performed at wide temperature region and the temperature dependence of the quantum effect of hydrogen molecule is addressed. The calculation results are compared with those of classical MD results. As a result, it is confirmed that the diffusivity of hydrogen molecule is changed depending on temperature by the quantum effect. It is clarified that this result can be explained that the dominant factor by quantum effect on the diffusivity of hydrogen changes from the swollening the potential to the shallowing the potential well around 30 K. Moreover, it is found that this tendency is related to the temperature dependency of the ratio of the quantum kinetic energy and classical kinetic energy.

    DOI: 10.1063/1.4897890

    Scopus

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  • Numerical Study of Real Gas Effects on Shock Tube Problems at Supercritical Conditions 査読有り

    MUTO Daiki, TSUBOI Nobuyuki, TERASHIMA Hiroshi

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN ( 一般社団法人 日本航空宇宙学会 )   12 ( 29 )   Po_2_39 - Po_2_44   2014年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Investigations of real gas effects of supercritical fluids on shock tube problems were numerically performed. Understandings of fluid behaviors under supercritical conditions are essential for the design of high pressure combustors. We developed a numerical code for simulations of flow fields under the supercritical conditions. Cubic types of equation of state are applied to evaluate properties of nearcritical and supercritical fluids. The present code was tested on shock tube problems, and the present result agreed well with a reference result. Comparisons of results between the real gas equations of state and the ideal gas equation of state showed differences in position of shock waves, contact discontinuities, and expansion fans due to the specific thermodynamic features of the supercritical fluids. In a condition that crosses the critical point, the results showed a large density jump with a small temperature jump at the contact discontinuity because of drastic changes of thermodynamic properties. This indicated that the real gas effects obviously appear when the initial condition is close to the critical point of the working fluids.

    DOI: 10.2322/tastj.12.Po_2_39

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/130004956821

  • 101 煤膜法による円管内でのメタン/酸素デトネーションのセル模様に関する実験的研究

    吉田 啓祐, 元永 孝英, 森井 雄飛, 村上 清人, 須佐 秋生, 坪井 伸幸, 林 光一

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _101 - 1_-_101-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._101-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951174

  • J0550204 分子動力学法による液体水素の輸送物性に対する量子効果の影響解析([J055-02]マイクロ・ナノスケール熱流体現象(2))

    永島 浩樹, 津田 伸一, 坪井 伸幸, 越 光男, 林 光一, 徳増 崇

    年次大会 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _J0550204 - -_J0550204-   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    In this study, we conducted analysis of quantum effect of hydrogen molecules on the energy transport of liquid hydrogen using classical Molecular Dynamics (MD) and path integral Centroid MD (CMD) method. We performed MD simulation across a wide temperature region in the constant density and compared the thermal conductivity of each method. The thermal conductivity was calculated using non-equilibrium MD method. As a result, it was confirmed that CMD shows lower thermal conductivity than classical MD and this tendency is consistent with experimental data. Moreover, it was clarified that because of the change of intermolecular potential due to the quantum effect, the potential energy transport by molecular motion and the energy transport by intermolecular interaction decrease.

    DOI: 10.1299/jsmemecj.2014._J0550204-

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009943927

  • J0550104 分子動力学シミュレーションによる臨界点近傍のニ原子分子流体に対する密度ゆらぎの評価([J055-01]マイクロ・ナノスケール熱流体現象(1))

    井川 祥平, 徳増 崇, 坪井 伸幸, 津田 伸一

    年次大会 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _J0550104 - -_J0550104-   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    In this study, we investigated the density fluctuation of diatomic fluids around the critical points for evaluation of the principle of corresponding state. We used Molecular Dynamics (MD) simulation against the 2-Center Lennard-Jones (2CLJ) fluids for extraction of structure of fluctuation around the critical points. We evaluated the density fluctuation by two methods. One is the dispersion of number of molecules at certain domain as time-averaged quantity. The other is the calculation of static structure factor. As the results, in 2CLJ fluids that have shorter molecular elongations comparatively, the principle of corresponding state is satisfied because of the small difference in the fluctuation structure extracted by the present two methods.

    DOI: 10.1299/jsmemecj.2014._J0550104-

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009943922

  • G0510306 3次元数値解析による高圧水素噴流の管内における自着火機構の解明([G051-03]流体工学部門一般セッション(3),流体工学部門)

    横山 瑛紀, 朝原 誠, 坪井 伸幸

    年次大会 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _G0510306 - -_G0510306-   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    One of self-ignition mechanisms of high-pressure hydrogen jet occurs by vortex caused from instability. Several studies about self-ignition of high-pressure hydrogen spouted from a tube attached with a tank are reported. In this analysis, the numerical study is performed to find out mechanism of self-ignition of hydrogen jet in a tube with a 10mm in diameter connected to a high pressure tank of 9.0MPa. Hydrogen and air are mixed at their contact surface to yield vortices, and the mixture ignites because the high temperature and high pressure regions are yielded behind the precursor shock wave.

    DOI: 10.1299/jsmemecj.2014._G0510306-

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009943304

  • G0510305 反射衝撃波と境界層の干渉による流れの3次元挙動に関する数値解析([G051-03]流体工学部門一般セッション(3),流体工学部門)

    若林 諒, 朝原 誠, 坪井 伸幸

    年次大会 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _G0510305 - -_G0510305-   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    At the reflected shock rear, a chemical reaction starts at a temperature and pressure constant static premixed gas conditions by filling reactive premixed gas in the shock tube, and reflects the shock wave in the pipe ends. Meyer and Oppenheim were classified into ignition two forms Mild Ignition and Strong Ignition, the start of the H2/O2 detonation due to the reflected shock wave. In order to ignite instantly in the tube cross-section of the entire near-wall reflection, Strong Ignition is a form ignition reaction theory. Mild Ignition is a firing mode hydrodynamic, under the influence of lambda shock wave generated by the mutual interference between the boundary layer and are reaching the ignition shock wave backward flow becomes multidimensional. Mark was revealed from the experiment due to the mutual interference between the boundary layer and the reflected shock, lambda shock wave to be formed in connection with this phenomenon. Thus, experiments by the reflected shock ignition is performed, there are cases in which ignition occurs is unexpected due to the interference of the reflected shock wave and boundary layer. In this study, we focus on the flow field due to the interference of the boundary layer and reflected shock, it is an object of the present invention to elucidate the flow three-dimensional.

    DOI: 10.1299/jsmemecj.2014._G0510305-

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009943303

  • G0510304 矩形管内を伝播するデトネーション波の多頭構造に関する3次元数値解析([G051-03]流体工学部門一般セッション(3),流体工学部門)

    朝原 誠, 長尾 剛史, 坪井 伸幸, 林 光一

    年次大会 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _G0510304 - -_G0510304-   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    Three-dimensional numerical analysis using practical scale of the experiment is performed to obtain cellular structure in rectangular tube. As a result, transverse wave in three-dimensions moves in different direction comparing with two-dimensional structure at the point of propagation structure. Furthermore, each transverse wave affects to accelerate the propagation velocity in circumferential direction and makes unreacted gas pockets after transverse wave goes through each other.

    DOI: 10.1299/jsmemecj.2014._G0510304-

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009943302

  • G0510303 数値解析によるローテーティングデトネーションエンジンの推力性能に関する研究([G051-03]流体工学部門一般セッション(3),流体工学部門)

    吉田 航, 朝原 誠, 坪井 伸幸

    年次大会 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _G0510303 - -_G0510303-   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    Study of detonation engine has been actively carried out in order to improve the thrust performance and expected to apply rocket engine. Even among them, rotating detonation engine has attracted attention. Many experiments have been performed, but in the experiments, varying the combustion chamber size is difficult. In this study, the numerical study is carried out to find out thrust performance with changing combustion chamber size.

    DOI: 10.1299/jsmemecj.2014._G0510303-

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009943301

  • 806 ローテーティングデトネーションエンジンの運転条件と性能評価 : 格子解像度がIspに与える影響

    渡辺 裕介, 坪井 伸幸, 原野 孝也, 小島 孝之, 林 光一

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _806 - 1_-_806-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._806-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951367

  • 802 超臨界圧力下における極低温同軸噴流への噴射器形状の及ぼす効果に関する数値解析

    武藤 大貴, 坪井 伸幸, 寺島 洋史

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _802 - 1_-_802-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._802-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951363

  • B213 分子動力学シミュレーションによる二原子分子流体の臨界点近傍における密度ゆらぎに関する研究

    井川 祥平, 徳増 崇, 坪井 伸幸, 永島 浩樹, 津田 伸一

    熱工学コンファレンス講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _B213 - 1_-_B213-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    In this study, we evaluated the density fluctuation of diatomic fluids around the critical point. We performed Molecular Dynamics (MD) simulation against 2-Center-Lenard-Jones (2CLJ) fluids that have molecular elongation as a parameter. We compared the density fluctuation of each fluid to evaluate the principle of corresponding state of density fluctuation. We evaluated the density fluctuation by dispersion of number of molecules, static structure factor, and intermediate scattering function. As the results, in 2CLJ fluids that have shorter molecular elongation comparatively, the principle of corresponding state of static fluctuation structure was satisfied.

    DOI: 10.1299/jsmeted.2014._B213-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009938965

  • 811 ハイブリッドロケット内部の3次元非定常圧縮性流れの数値解析 : 乱流モデルによる影響

    坂本 まい, 武藤 大貴, 坪井 伸幸

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _811 - 1_-_811-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._811-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951372

  • 808 数値解析によるエアロスパイクノズルの性能評価 : 内部ノズルの性能評価

    芝尾 将史, 坪井 伸幸, 伊藤 隆

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _808 - 1_-_808-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._808-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951369

  • 804 Waverider形状の熱的影響に関する数値解析

    浦 優介, 衞藤 遥, 坪井 伸幸, 丸 祐介, 藤田 和央

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _804 - 1_-_804-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._804-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951365

  • 523 固体高分子形燃料電池触媒層一次細孔内の酸素輸送挙動に関する分子動力学的解析

    出口 将嗣, 福島 啓悟, 坪井 伸幸, 徳増 崇

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _523 - 1_-_523-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._523-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951304

  • 219 極超音速流れにおけるランプ模型周りの場数値解析 : ランプ角度の影響

    黒川 久仁彦, 坪井 伸幸, 倉本 健史

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _219 - 1_-_219-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._219-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951222

  • 1404 H_2/O_2混合気中における衝撃波収束による着火の機構に関する数値解析

    朝原 誠, 三谷 奈々, 坪井 伸幸

    流体工学部門講演会講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _1404 - 1_-_1404-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    A reflected shock wave by focusing reflector is simulated using the Navier-Stokes equations with the detailed oxy-hydrogen reaction mechanism. Into the tube which has focusing end wall, ignition successes around focal point under the no-ignition condition at the flat wall. The shock focusing is one of effective way of detonation initiation. However, the ignition mechanism from shock focusing is not clear. In this study, we aim to indicate the ignition phenomena induced by shock focusing.

    DOI: 10.1299/jsmefed.2014._1404-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009938781

  • 102 数値計算によるローティングデトネーションエンジンの推進性能評価 : 回転デトネーションの数及び燃焼器サイズによる影響

    原野 孝也, 渡辺 裕介, 坪井 伸幸, 小島 孝之, 林 光一

    日本機械学会九州支部講演論文集 ( 一般社団法人 日本機械学会 )   2014 ( 0 )   _102 - 1_-_102-2_   2014年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    DOI: 10.1299/jsmekyushu.2014.67._102-1_

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110009951175

  • A molecular dynamics analysis of quantum effect on the thermodynamic properties of liquid hydrogen 査読有り

    Nagashima H., Tsuda S., Tsuboi N., Koshi M., Hayashi A., Tokumasu T.

    ASME 2013 11th International Conference on Nanochannels, Microchannels and Minichannels, ICNMM 2013   2013年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Liquid Hydrogen plays an important role in hydrogen energy society. Therefore it is important to understand its thermal and transport properties accurately. However cryogenic hydrogen has unusual thermodynamic properties because of its quantum nature. The thermal de Broglie wavelength of cryogenic hydrogen molecule becomes the same order as molecular diameter. Therefore, each molecular position and its momentum cannot be defined classically. Because of this nature, hydrogen molecules show higher diffusivity than classical counterpart. Until now, the effects of quantum nature of hydrogen and its mechanism on the thermodynamic properties have not been clarified in detail. Especially, how the quantum nature would effect on the energy transfer in molecular scale has not been clarified. An accurate understanding of the effect and mechanism of quantum nature is important for hydrogen storage method and energy devices which use hydrogen as a fuel. In this study, therefore, we investigated the effect of this quantum nature and its mechanism on the thermodynamic and transport properties of cryogenic hydrogen using classical Molecular Dynamics (MD) method and quantum molecular dynamics method. We applied path integral Centroid Molecular Dynamics (CMD) method for the analysis. First, we have conducted thermodynamic estimation of cryogenic hydrogen using the MD methods. This simulation was performed across a wide density-temperature range. Using these results, equations of state (EOS) were obtained by Kataoka's method, and these were compared with experimental data according to the principle of corresponding states. As a result, it was confirmed that both quantitative and qualitative effect of the quantum nature on the thermodynamic properties of hydrogen are large. It was also found that taking account the quantum nature makes larger virial pressure and weaker intermolecular interaction energy. Second, we have calculated the diffusion coefficient of liquid hydrogen to clarify the effect of the quantum nature on the transport properties. We used Green-Kubo form for the calculation using velocity autocorrelation function. The simulation was performed across a wide temperature range. CMD simulation results were compared with classical simulation results and experimental data. We clarified the effect of quantum nature on the transport properties of liquid hydrogen. Copyright © 2013 by ASME.

    DOI: 10.1115/ICNMM2013-73161

    Scopus

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  • An analysis of quantum effect on the p-V-T relation of cryogenic hydrogen using centroid molecular dynamics method 査読有り

    Nagashima H., Tsuda S., Tsuboi N., Koshi M., Koichi Hayashi A., Tokumasu T.

    Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B   79 ( 805 )   1848 - 1857   2013年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    In this paper, we conducted analysis of p-V-T relation of cryogenic hydrogen using classical Molecular Dynamics (MD) and path integral Centroid MD (CMD) method to understand an effect of quantum nature of hydrogen molecules. We performed NVE constant MD simulation across a wide density-temperature region to obtain an Equation Of State (EOS). Simulation results were compared with experimental data. As a result, it was confirmed that classical MD cannot reproduce the experimental data at the high density region. On the other hand, CMD well reproduces the thermodynamic properties of liquid hydrogen. Moreover, it was clarified that taking the quantum effect into account makes repulsion force larger and the potential well smaller. Because of this mechanism, the intermolecular interaction of hydrogen diminishes and the virial pressure increases. ©2013 The Japan Society of Mechanical Engineers.

    DOI: 10.1299/kikaib.79.1848

    Scopus

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  • Strong and Mild Ignition Mechanism behind Reflected Shock Waves in Hydrogen Mixture 査読有り

    Asahara, M., Shirakawa, Y., Hayashi, A.K. , Tsuboi, N.

    5th International Conference on Hydrogen Safety   No: 167   2013年09月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical analysis of spinning detonation dependency on initial pressure using AUSMDV scheme 査読有り

    Nagao T., Asahara M., Koichi Hayashi A., Tsuboi N., Yamada E.

    51st AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition 2013   2013年08月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    In order to investigate the fundamental characteristics of spinning detonation propagating tubes, this present study shows a numerical simulation using AUSMDV scheme which is more capable to capture detonation phenomenon clearly than TVD scheme and a detailed chemical kinetic model of H2/O2 by Petersen and Hanson. By analyzing the lower limit of spinning detonation propagation, disclosing the detonation propagation limit and the feature is the present purpose. In the numerical results, the lower limit of spinning detonation propagating in a rectangular tube has partially analyzed. The numerical results indicated the differences of the propagation limit of spinning detonation propagating in between a circular tube and a rectangular tube. Because of the number of transverse wave, spinning detonation propagating in rectangular tube is able to maintain more than circular tube's one. © 2013 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

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  • Numerical Study on Shock Wave Interaction over Compression Corner with 30 deg. in Hypersonic Flow 査読有り

    T.Kuramoto, D.Muto, N.Tsuboi, H.Nagai, K.Asai

    29th International Symposium on Shock Waves   #0246-000035   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Analysis of 3D-Rotating Detonation Engine Concerning Propagation Mechanism in Combustor Thickness Direction and Effect on its Performance 査読有り

    Zusai K., Uemura Y., Asahara M., Yamada E., Hayashi A.K., Tsuboi N.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #251   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Detailed Hydrodynamic Instability Structure at Hydrogen/Air Detonation Front Using WCNS Scheme 査読有り

    Iida R., Asahara M., Tsuboi N., Nonomura T., Hayashi A.K.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #234   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Thrust Performance Estimation on Rotating Detonation Engine Using Two-Dimensional Numerical Simulations Isp under Low-Pressure Environment 査読有り

    Watanabe Y., Tsuboi N., Kojima T., Hayashi A.K.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #117   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Experimental Study on CH4/O2 Detonation Characteristics near Propagation Limit: Influence of Initial Pressure and Equivalence Ratio on Cellular Structure 査読有り

    Motonaga T., Yoshida K., Morii Y., Murakami K., Susa A., Tsuboi N., Hayashi A.K.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #237   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Simulations on Propagating Process of H2/O2/H2O Cylindrical Detonation with Detailed Reaction Model 査読有り

    Sugiyasu T., Morii Y., Tsuboi N., Asahara M., Hayashi A.K.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #158   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Three-Dimensional Simulation on Deflagration to Detonation Transition with a Detailed Chemical Reaction 査読有り

    Machida T., Fukuda M., Asahara M., Yamada E., Hayashi A.K., Tsuboi N.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #252   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Evaluation of Chemical Reaction Models and Numerical Simulations of Detonations in C2H4/O2 Mixtures 査読有り

    Araki T., Morii Y., Tsuboi N., Hayashi A.K.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #57   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Analysis on Ignition Problem behind Reflected Shock Waves in Reactive Mixture 査読有り

    Asahara M., Koyama T., Hayashi A.K., Tsuboi N.

    24th International Colloquium on the Dynamics of Explosions and Reactive Systems   #256   2013年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical approach to one-dimensional CH<inf>4</inf>/O<inf>2</inf> detonation with the reduced chemical kinetic model DRG30 査読有り

    Morii Y., Tsuboi N., Ogawa H., Tokudome S., Koichi Hayashi A.

    Science and Technology of Energetic Materials   73 ( 5-6 )   169 - 174   2012年09月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    In order to understand the effect of the CH4/O2 chemical kinetic models for detonation phenomena, the numerical calculations use one detailed chemical kinetic model k311 and four reduced chemical kinetic models such as DRG30 model, DRG23 model, Petersen & Hanson model, and Soetrisno model. At first, the calculations of laminar flame velocity and onedimensional ZND model are performed to compare with k311 model. Then, it is shown that DRG30 model is the most reliable reduced chemical kinetic model in four reduced kinetic models in these conditions. Next, the one-dimensional Euler simulations are performed with k311 model, DRG30 model, Petersen & Hanson model, and Soetrisno model. The results are discussed about detonation velocity history, and instantaneous pressure and temperature profiles. The detonations using k311, DRG30, and Petersen & Hanson models can propagate unstably, but Soetrisno model cannot reproduce a detonation. As a result, the similar features appear between the results with k311 model and DRG30 model.

    Scopus

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  • Numerical study and performance evaluation for a pulse detonation engine with an exhaust nozzle (1st report: Estimation on performance using a detailed reaction model) 査読有り

    Kimura Y., Tsuboi N., Tsuboi N., Hayashi A., Yamada E.

    Transactions of the Japan Society for Aeronautical and Space Sciences   55 ( 1 )   51 - 59   2012年02月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    This paper presents a propulsive performance evaluation for a H 2/Air pulse detonation engine (PDE) equipped with a converging-diverging exhaust nozzle. The evaluation was conducted using system-level modeling and multi-cycle numerical simulations. This study discusses two-dimensional and axisymmetric compressible Euler equations with a detailed chemical reaction model. First, the single-shot propulsive performance of a simplified-PDE (i.e., no exhaust nozzle) is evaluated to show the validity of the numerical and performance evaluation method. The influences of the initial conditions, ignition energy, grid resolution and scale effects on the propulsive performance are studied using multi-cycle simulations. The present results are compared with the results calculated by Ma et al. and Harris et al. The differences between their results and the present simulations are approximately 2-3% because their chemical reactions use a one-step model with a single-γ model. The effects of the specific heat ratio should be estimated for various nozzle configurations and flight conditions. © 2012 The Japan Society for Aeronautical and Space Sciences.

    Scopus

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  • An estimation of thermodynamic and transport properties of cryogenic hydrogen using classical molecular simulation 査読有り

    Nagashima H., Tokumasu T., Tsuda S., Tsuboi N., Koshi M., Hayashi A.

    ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011   2   289 - 299   2011年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    In this paper, we estimated the thermodynamic and transport properties of cryogenic hydrogen using classical molecular simulation to clarify the limit of classical method on the estimation of those properties of cryogenic hydrogen. Three empirical potentials, the Lennard-Jones (LJ) potential, two-center Lennard-Jones (2CLJ) potential, and modified Buckingham (exp-6) potential, and an ab initio potential model derived by the molecular orbital (MO) calculation were applied. Molecular dynamics (MD) simulations were performed across a wide density-temperature range. Using these data, the equation of state (EOS) was obtained by Kataoka's method, and these were compared with NIST (National Institute of Standards and Technology) data according to the principle of corresponding states. Moreover, we investigated transport coefficients (viscosity coefficient, diffusion coefficient and thermal conductivity) using time correlation function. As a result, it was confirmed that the potential model has a large effect on the estimated thermodynamic and transport properties of cryogenic hydrogen. On the other hand, from the viewpoint of the principle of corresponding states, we obtained the same results from the empirical potential models as from the ab initio potential, showing that the potential model has only a small effect on the reduced EOS: the classical MD results could not reproduce the NIST data in the high-density region. This difference is thought to arise from the quantum effect in actual liquid hydrogen. Copyright © 2011 by ASME.

    DOI: 10.1115/AJK2011-36005

    Scopus

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  • Dependency of Equivalence Ratio on Hydrogen Cylindrical Detonation Induced by Direct Initiation 査読有り

    Asahara, M., Tsuboi, N. Hayashi, A.K. and Yamada, E.

    The 4th International Conference on Hydrogen Safety (ICHS) 2011, paper no.224   2011年09月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Fast Deflagration in the Smooth Tube in Hydrogen-Oxygen Mixture 査読有り

    Edyta Dzieminska, Nobuyuki Tsuboi, A.Koichi Hayashi, Eisuke Yamada, Motoki Fukuda

    23rd International Colloquium on the Dynamics of Explosions and Reactive Systems, Poster 185   2011年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Oscillating propagation of near-limit detonations of CH4/O2 system in a small diameter tubes 査読有り

    2) Akio Susa, Nobuyuki Tsuboi, Takuma Endo, Youhi Morii, Hiroyuki Yokoyama, Syunsuke HASEGAWA, Yosuke OGAWA

    23rd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 131   2011年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Detailed Shock Configuration of Cylindrical Cellular Detonation 査読有り

    Makoto Asahara, Nobuyuki Tsuboi, A.Koichi Hayashi

    23rd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 324   2011年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Simulation on Two-Dimensional Detonation including Boundary Layer Effects 査読有り

    Nobuyuki Tsuboi, A.Koichi Hayashi, Youhi Morii, Mitsuo Koshi

    23rd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 187   2011年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Physics of Detonation Propagation in Rotating Detonation Engine 査読有り

    Takayuki Yamada, Nobuyuki Tsuboi, Yuho Uemura, A.Koichi Hayashi, Eisuke Yamada

    23rd International Colloquium on the Dynamics of Explosions and Reactive Systems, Poster 173   2011年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Two-dimensional analysis of Hydrogen/Oxygen cylindrical detonation using AUSMDV scheme 査読有り

    Makoto Asahara, Nobuyuki Tsuboi, A. Koichi Hayashi, and Eisuke Yamada

    Archivum Combustions   30 ( 3 )   177 - 186   2011年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Transition to detonation after a ‘volume explosion’ - Oppenheim’s experiment validation with a numerical calculation 査読有り

    Edyta Dzieminska, Motoki Fukuda, A. Koichi Hayashi, Nobuyuki Tsuboi

    Archivum Combustions   30 ( 3 )   187 - 195   2011年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Updated kinetic mechanism for high-pressure hydrogen combustion 査読有り

    Shimizu K., Hibi A., Koshi M., Morii Y., Tsuboi N.

    Journal of Propulsion and Power   27 ( 2 )   383 - 395   2011年03月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    A chemical kinetic model for high-pressure combustion of H 2=O2 mixtures has ben developed by updating some of the rate constants important under high-pressure conditions without any diluent. The revised mechanism is validated against experimental shock-tube ignition delay times and laminar flame speeds. Predictions of the present model are also compared with those by several other kinetic models proposed recently. Although predictions of those models (including the present model) agree quite well with each other and with the experimental data of ignition delay times and flame speeds at pressures lower than 10 atm, substantial differences are observed between recent experimental data of high-pressure mass burning rates and model predictions, as well as among the model predictions themselves. Different pressure dependencies of mass burning rates above 10 atm in different kinetic models result from using different rate constants in these models for HO 2 reactions, especially for H + HO2 and OH + HO 2 reactions. The rate constants for the reaction H + HO2 involving different product channels were found to be very important for the prediction of high-pressure combustion characteristics. An updated choice of rate constants for those reactions is presented on the basis of recent experimental and theoretical studies. The role of O(1D), which can be produced by the H + HO2 reaction, in the high-pressure combustion of H2 is discussed. © 2010 by the American Institute of Aeronautics and Astronautics, Inc.

    DOI: 10.2514/1.48553

    Scopus

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  • Mechanism of high-pressure hydrogen auto-ignition when spouting into air 査読有り

    Yamada E., Kitabayashi N., Hayashi A., Tsuboi N.

    International Journal of Hydrogen Energy   36 ( 3 )   2560 - 2566   2011年02月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    High-pressure hydrogen leak is one of the top safety issues presently. This study elucidates numerically the physics and mechanism of high-pressure hydrogen jet ignition when the hydrogen suddenly spouts into the air through a tube. The direct numerical simulation based on the compressible fluid dynamics was carried out. When high-pressure hydrogen is passing through the tube filled by atmospheric air, a strong shock wave is formed and heats up hydrogen behind the shock wave by compression effect. The leading shock wave is expanded widely after the tube exit, auto-ignitions of hydrogen occur. When the tube becomes longer, the tendency of auto-ignition is increased. Other type of auto-ignitions is also predicted. An explosion is also occurred in the tube under a certain condition. Vortices are generated behind the shock wave in a long tube. There is a possibility of an auto-ignition induced by vortices. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.ijhydene.2010.05.011

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  • Numerical Study on Detonation Characteristics Using a Bio-Fuel 査読有り

    A. Hayashi, T.Shimada, E. Yamada, N. Tsuboi

    AIAA-2011-582, 49th AIAA Aerospace Sciences Meeting   2011年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Study and Performance Evaluation for Pulse Detonation Engine with an Aerospike Nozzle 査読有り

    N. Tsuboi, Y. Kawakami, K. Ezure, A. Hayashi, E. Yamada

    AIAA-2011-800, 49th AIAA Aerospace Sciences Meeting   2011年01月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical analysis of threshold of limit detonation in Rotating Detonation Engine 査読有り

    Yamada T., Hayashi A., Yamada E., Tsuboi N., Tangirala V., Fujiwara T.

    48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition   2010年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    Rotating Detonation Engine (RDE) is a new kind of detonation engine, which may provide a high performance with a smaller and simpler system than the traditional ones. In order to optimize RDE system, the threshold of detonation limit must be studied for its best design and its best run. In this paper, the following four aspects are discussed: (1) what will be happen to the rotating detonation limit when the computational area is doubled; (2) what will be happen to rotating detonation when the ignition energy is increased; (3) what will be happen to specific impulse (Isp) when the ignition energy is increased. The results show that the lower detonation limit gets the computational area effct, but the upper one does not. The max specific impulse of Ispf is about 4000 s and that of Ispm is about 450 s. Copyright © 2010 by the American Institute of Aeronautics and Astronautics, Inc.

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  • Combustion characteristics of hydroxylammonium nitrate aqueous solutions 査読有り

    Katsumi T., Matsuda R., Inoue T., Tsuboi N., Ogawa H., Sawai S., Hori K.

    International Journal of Energetic Materials and Chemical Propulsion   9 ( 3 )   219 - 231   2010年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Hydroxylammonium nitrate (HAN) based liquid propellant has been investigated as a candidate for the monopropellant to be utilized in the reaction control system of satellites as an alternative to hydrazine. This propellant, which consists of ammonium nitrate, methanol, and water, has moderate burning characteristics, sufficiently low freezing temperature, high density, low toxicity, and its density x Isp is 70% higher than hydrazine. In a previous study, the combustion characteristics of the propellants were obtained and found to be very complex. In this paper, the research was focused on the combustion characteristics of HAN aqueous solution. Sample solutions of several concentrations, 95-50 mass %, were prepared. The measurement of linear burning rates, the temperature measurement of the combustion wave, and the observation of combustion phenomena were included in the study. The linear burning rate does not increase monotonically with increasing HAN concentration. The burning rates increase as the HAN concentration increases up to 80 mass %, and decrease as the concentration increases from 80 to 95 mass %. The burning rate peaks at around 80 mass % of HAN concentration. The combustion mode is very complex and is dependent upon composition and pressure. Temperature measurements indicate that the role of the two-phase region is very important, and the boiling of water caused by superheat is responsible for the high burning rate. The relationship between the rate of nucleation of bubbles and the linear burning rate is discussed. © 2010 by Begell House, Inc.

    DOI: 10.1615/IntJEnergeticMaterialsChemProp.v9.i3.30

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  • Numerical investigations of film cooling effect on sub-scale rocket engine performance 査読有り

    Ito T., Tsuboiy N., Miyajima H.

    Transactions of the Japan Society for Aeronautical and Space Sciences   53 ( 179 )   63 - 70   2010年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    LOX/LH 2 subscale rocket nozzle flow fields are simulated computationally using the 3D compressible Navier- Stokes equations. The area ratio of the nozzle is 140 and the film coolant hydrogen gases are injected from 30 film cooling holes distributed circumferentially at an area ratio of 13. The experimental nozzle throat Reynolds number indicates that the boundary layer of the nozzle is in its transition region as the size of the nozzle is small. A clear difference in effective specific impulses of the secondary flow between the laminar and turbulent conditions is also shown. The nozzle wall temperature also influences the nozzle performance and the experimental performances were in better agreement with the laminar computations when the wall temperature is set to 300 K, which is closer to the experimental conditions. Both turbulent and laminar computations are carried out to investigate the effect of the boundary layer conditions on the nozzle performance. The computed results show that the structure of the separated flow downstream of the film cooling injection significantly changes between the turbulent and laminar conditions. © 2010 The Japan Society for Aeronautical and Space Sciences.

    DOI: 10.2322/tjsass.53.63

    Scopus

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  • Mechanism of High Pressure Hydrogen Auto-ignition When Spouting into Air 査読有り

    E.Yamada,Naoki Kitabayashi,A. Koichi Hayashi,Nobuyuki Tsuboi

    International Journal of Hydrogen Energy   36 ( 2560-2566 )   2010年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Advanced Computer Science on Internal Ballistics of Solid Rocket Motors 査読有り

    Toru SHIMADA,Kazushige KATO,Nobuhiro SEKINO,Nobuyuki TSUBOI,Yoshio SEIKE,Mihoko FUKUNAGA,Yu DAIMON,Hiroshi HASEGAWA,Hiroya ASAKAWA

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN   8 ( ists27 )   Pa_29 - Pa_37   2010年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    CiNii Article

  • Detonation Limit Thresholds in H2/O2 Rotating Detonation Engine 査読有り

    Takayuki Yamada,A.Koichi Hayashi,Eisuke Yamada,Nobuyuki Tsuboi,Venkat E. Tangirala,Toshi Fujiwara

    Combustion Science and Technology   182 ( 11-12 )   1901 - 1914   2010年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1080/00102202.2010.498676

    Scopus

  • 90°曲管におけるH2/O2デトネーションの流体力学的効果に関する数値解析 査読有り

    坪井 伸幸,阿達 聡,林 光一,山田 英助,内田 正宏,藤森 俊郎,須田俊之

    日本燃焼学会誌論文集   52 ( 161 )   213 - 223   2010年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • ノーズコーンをもつ超音速機の壁面圧力を用いた機体姿勢およびマッハ数計測に関する数値解析 査読有り

    吹場活佳,坪井伸幸,小林弘明

    日本航空宇宙学会論文集   58 ( 676 )   130 - 137   2010年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Numerical Investigations of the Film Cooling Effect on Sub-Scale Rocket Engine Performance 査読有り

    Takashi ITO,Nobuyuki TSUBOI,Hiroshi MIYAJIMA

    Transactions of the Japan Society for Aeronautical and Space Sciences   53 ( 179 )   63 - 70   2010年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 排気ノズルを有するパルスデトネーションエンジンの数値解析による推力性能評価(第1報:詳細反応モデルによる基本性能の評価) 査読有り

    木村勇一朗,坪井伸幸,林光一,山田英助

    日本航空宇宙学会論文集   58 ( 675 )   91 - 99   2010年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Reliability of Classical Molecular Dynamics Method to Thermodynamic Properties of Hydrogen 査読有り

    H.Nagashima, T.Tokumasu, S.Tsuda, N.Tsuboi, A.K.Hayashi

    AIAA-2010-991, 48th AIAA Aerospace Sciences Meeting, 2010   2010年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Analysis of Threshold of Limit Detonation in Rotating Detonation Engine 査読有り

    T.Yamada, A.K.Hayashi, E.Yamada, N.Tsuboi, V.E.Tangirala, T.Fujiwara

    AIAA-2010-153, 48th AIAA Aerospace Sciences Meeting, 2010   2010年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

  • Numerical Study and Performance Evaluation for Pulse Detonation Engine With Exhaust Nozzle 査読有り

    N.Tsuboi,Y.Kimura,A.K.Hayashi,V.E. Tangirala

    45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, AIAA-2009-5315, 2009   2009年07月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年07月  -  2009年07月

    主要論文集(会議)

  • Development of Supersonic Vehicle for Demonstration of a Precooled Turbojet Engine 査読有り

    Shujiro SAWAI,Kazuhisa FUJITA,Hiroaki KOBAYASHI,Shin'ichiro SAKAI,Nobutaka BANDO,Shouhei KADOOKA,Nobuyuki TSUBOI,Koji MIYAJI,Taku UCHIYAMA,Tatsuaki HASHIMOTO

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, SPACE TECHNOLOGY JAPAN   7 ( ists26 )   Tg_27 - Tg_34   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Combustion Characteristics of a Hydroxylammonium Nitrate Based Liquid Propellant. Combustion Mechanism and Application to Thrusters 査読有り

    T.Katsumi,H.Kodama,T.Matsuo,H.Ogawa,N.Tsuboi,K.Hori

    Combustion, Explosion, and Shock Waves   45 ( 4 )   442 - 435   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Combustion Mechanism of Tetra-Olglycidyl Azide Polymer and Its Application to Hyprid Rocket 査読有り

    Wada,Y.,Seike,Y.,Nishioka,M.,Tsuboi,N.,Shimada,T.,Hasegawa,K.,Kobayashi,K.,Hori,K.

    Advancements in Energetic Materials and Chemical Propulsion   1099 - 1114   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Combustion Characteristics of HAN-Based Liquid Monopropellant 査読有り

    Katsumi,T. Kodama,H.,Shibamoto,H.,Nakatsuka,J.,Hasegawa,K.,Kobayashi,K.,Ogawa,H.,Tsuboi,N.,Sawai,S.,Hori,K.

    Advancements in Energetic Materials and Chemical Propulsion   125 - 139   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Combustion Characteristics of HAN-Based Liquid Monopropellant 査読有り

    Katsumi,T. Kodama,H.,Ogawa,H.,Tsuboi,N.,Sawai,S.,Hori,K.

    Science and Technology of Energetic Materials   70 ( 2 )   27 - 32   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Numerical Simulation of Single Spinning and Two-Headed Detonation in a Circular Tube 査読有り

    Tsuboi,N.,Daimon,Y.,Hayashi,A.K

    Advancements in Energetic Materials and Chemical Propulsion   1076 - 1084   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Combustion mechanism of tetra-ol glycidyl azide polymer 査読有り

    Wada,Y.,Seike,Y.,Tsuboi,N.,Hasegawa,K.,Kobayashi,K.,Nishioka,N.,Keiichi Hori

    Science and Technology of Energetic Materials   69 ( 5 )   143 - 147   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • The Determination of the Third Body Efficiencies for the H+O2+M=HO2+M reaction (M=Ar, H2O) 査読有り

    Morii,Y.,Tsuboi,N.,Koshi,M.,Ogawa,H.,Hayashi,A.K.,Shimizu,T.

    Science and Technology of Energetic Materials   70 ( 5 )   117 - 121   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Numerical Study on Propagation of Spherical Detonation 査読有り

    Asahara,M.,Tsuboi,N.,Hayashi,A.K.,Yamada,E.

    Science and Technology of Energetic Materials   70 ( 2 )   49 - 52   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Numerical Simulation of H2/Air Detonation Using Unstructured Mesh 査読有り

    Togashi,F.,L&ouml;hner,R.,Tsuboi,N.

    Shock Waves   19 ( 2 )   151 - 162   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Energy Release Effect of Mixture on Single Spinning Detonation Structure 査読有り

    Tsuboi,N.,Hayashi,A.K.,Koshi,M.

    Proceedings of the Combustion Institute   32   2405 - 2412   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • A Numerical Analysis of the Auto-Ignition of a High Pressure Hydrogen Jet Provided by a Thin Tube 査読有り

    Yamada,E.,Watanabe,S.,Hayashi,A.K.,Tsuboi,N.

    Proceedings of the Combustion Institute   32   2363 - 2369   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Spinning Detonation and Velocity Deficit in Small Diameter Tubes 査読有り

    Kitano,S.,Fukao,M.,Susa,A.,Tsuboi,N.,Hayashi1,A.K.,Koshi,M.

    Proceedings of the Combustion Institute   32   2355 - 2362   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Combustion Model of Tetra-ol Glycidyl Azide Polymer 査読有り

    Wada,Y.,Tsuboi,N.,Hori,K.,et al.

    Proceedings of the Combustion Institute   32   2005 - 2012   2009年04月

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)

  • Numerical Simulation of JP10/Air Two-Phase Detonation 査読有り

    Masuda,N.,Tangirala,V.,Benkiewicz,K.,Hayashi,A.K.,Tsuboi,N.

    Advancements in Energetic Materials and Chemical Propulsion   423 - 438   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • A Modeling of Thermal Properties of Hydrogen/Oxygen System Using Molecular Simulations 査読有り

    S.Tsuda,N.Yamanishi,T. Tokumasu,N.Tsuboi,Y.Matsumoto

    AIAA 2009-1601, 47th AIAA Aerospace Sciences Meeting   2009年04月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Thresholds of Detonation Limit in H2/O2 Rotating Detonation Engine 査読有り

    Takayuki Yamada,A. Koichi Hayashi,Eisuke Yamada,Nobuyuki Tsuboi,and Venkat E. Tangirala

    22nd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 156 (2009)   2009年04月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Numerical Analysis on the Correlation between Transverse Wave Strength and Detonation Velocity 査読有り

    Kuninori Togai,Nobuyuki Tsuboi,A. Koichi Hayashi1,Eisuke Yamada

    22nd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 189 (2009)   2009年04月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Numerical Simulation on Two-Dimensional Detonation with Boundary Layer 査読有り

    Nobuyuki Tsuboi,A.Koichi Hayashi Mitsuo Koshi

    22nd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 145 (2009)   2009年04月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

    主要論文集(会議)

  • Reduced Chemical Reaction Modelof Methane/Oxygen Mixture 査読有り

    Youhi Morii,Nobuyuki Tsuboi,Mitsuo Koshi,Hiroyuki Ogawa,A.Koichi Hayashi,Taro Shimizu

    22nd International Colloquium on the Dynamics of Explosions and Reactive Systems, Poster 148 (2009)   2009年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Numerical study on auto-ignition of a high pressure hydrogen jet in a tube having a gap 査読有り

    Naoki Kitabayashi,Eisuke Yamada,A. Koichi Hayashi,Nobuyuki Tsuboi

    22nd International Colloquium on the Dynamics of Explosions and Reactive Systems, Oral 154 (2009)   2009年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Numerical Study on Propagating Process of H2/O2 Cylindrical Detonation with Detailed Reaction Model 査読有り

    Makoto Asahara,Nobuyuki Tsuboi,A. Koichi Hayashi,Eisuke Yamada

    22nd International Colloquium on the Dynamics of Explosions and Reactive Systems, Poster 161 (2009)   2009年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Numerical Study on the Heat Transfer of the Flow With Endothermic Chemical Reaction 査読有り

    K. Fukiba,N. Tsuboi,R. Minato

    45th AIAA/ASME/SAE/ASEE Joint Propulsion ConferenceAIAA-2009-5461m 2009   2009年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • A Noble Kinetic Model of H2/O2 System Applicable to Liquid Rocket Engine Combustion 査読有り

    K. Shimizu,H.Hibi,M. Koshi,Y. Morii,N.Tsuboi

    45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, AIAA-2009-4968, 2009   2009年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

    主要論文集(会議)

  • Mechanism of High Pressure Hydrogen Auto-ignition When Spouting into Air 査読有り

    E. Yamada,N. Kitabayashi,A.K. Hayashi,N. Tsuboi

    International Conference on Hydrogen Safety (ICHS3), Ajaccio, France, September 2009   2009年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年04月  -  2009年04月

  • Sensitivity Analysis of Rotating Detonation Engine with a Detailed Reaction Model 査読有り

    A.K.Hayashi,Y.Kimura,T.Yamada,E.Yamada,J.Kindracki,E.Dzieminska,P. Wolanski,N.Tsuboi,V.E. Tangirala,T.Fujiwara

    AIAA 2009-0633, 47th AIAA Aerospace Sciences Meeting   2009年01月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年01月  -  2009年01月

  • Effects of Chemical Reaction Model on H2/O2 Detonation at High Pressures 査読有り

    S.Adachi,A.K.Hayashi,Y. Morii,N.Tsuboi,E.Yamada

    AIAA 2009-0441, 47th AIAA Aerospace Sciences Meeting   2009年01月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2009年01月  -  2009年01月

  • Numerical Study and Performance Prediction for Gaseous Hydrogen/Oxygen Bell Nozzle 査読有り

    Tsuboi,N.,Ito,T.,Miyajima,H.

    Transactions of the Japan Society for Aeronautical and Space Sciences   51 ( 172 )   86 - 92   2008年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Effects of Initial Pressure on Single Spinning Detonation in a Square Tube 査読有り

    Tsuboi N.,Asahara,M.,Hayashi,A.K.

    Science and Technology of Energetic Materials   69 ( 5 )   173 - 176   2008年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 気球を利用した無重力実験のための機体開発とそのフライト結果 査読有り

    澤井秀次郎,橋本樹明,坂井真一郎,坂東信尚,小林弘明,藤田和央,吉光徹雄,石川毅彦,稲富裕光,福家英之,鎌田幸男,星野慎二,田島賢一,門岡昇平,上原聡,小島孝之,上野誠也,宮路幸二,坪井伸幸,平木講儒,鈴木宏二郎,松嶋清穂,中田孝

    日本航空宇宙学会論文集   56 ( 654 )   339 - 346   2008年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • フィルム冷却を考慮した液酸/液水ロケットエンジン性能解析 査読有り

    伊藤隆,坪井伸幸,宮島博

    日本航空宇宙学会論文集   56 ( 659 )   551 - 557   2008年04月

     詳細を見る

    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Numerical Simulation of Spinning Detonation in Square Tube 査読有り

    Tsuboi,N.,Asahara,M.,Eto,K.,Hayashi,A.K.

    Shock Waves   18 ( 4 )   329 - 344   2008年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Three-dimensional Numerical Simulation of Detonations in Coaxial Tubes 査読有り

    Tsuboi,N.,Daimon,Y.,Hayashi,A.K.

    Shock Waves   18   379 - 392   2008年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Internal and External Flow of Rocket Nozzle 査読有り

    Shimizu,T.,Kodera,M.,Tsuboi,N.

    Journal of the Earth Simulator   9 ( 3 )   19 - 26   2008年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Nonequilibrium Rotational Temperature Measurements over Flat Plate in Hypersonic Rarefied Gas Flow 査読有り

    N.Tsuboi,Y.Matsumoto

    26th International Symposium on Rarefied Gas Dynamics   545 - 550   2008年04月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2008年04月  -  2008年04月

  • Fundamental Study on Pressure Oscillation in a Liquid Rocket Engine Combustion Chamber 査読有り

    Shimizu,T.,Mizobuchi,Y.,Tsuboi,N.

    44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, AIAA 2008-4548   2008年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2008年04月  -  2008年04月

  • Aerodynamic Design of Balloon- Based Operation Vehicle for Precooled Turbojet Engine Demonstration 査読有り

    K. Fujita,N. Tsuboi,S. Sawai,H. Kobayashi,K. Miyaji,T. Uchiyama

    AIAA-2008-2658, 15th AIAA International Space Planes and Hypersonic Systems and Technologies Conference   2008年04月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2008年04月  -  2008年04月

  • Visualization of the Heat Flux Distribution on a Blunt-nosed body with an Aerospike in Hypersonic Flow 査読有り

    S.Ha,H. Nagai,K.Asai,K.Nakakita,N.Tsuboi

    2008 KSAS-JSASS Joint International Symposium on Aerospace Engineering   333 - 339   2008年04月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    2008年04月  -  2008年04月

  • 3次元爆轟現象の数値解析

    坪井伸幸,林光一

    ながれ ( 日本流体力学会 )   26 ( 3 )   183 - 192   2007年07月

     詳細を見る

    担当区分:責任著者   記述言語:日本語   掲載種別:記事・総説・解説・論説等(学術雑誌)

  • 3次元爆轟現象の数値解析 査読有り

    坪井伸幸,林光一

    日本流体力学会誌「ながれ」   26   183 - 192   2007年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Detailed Structure of Spinning Detonation in a Circular Tube 査読有り

    Tsuboi,N.,Eto,K.,Hayashi,A.K.

    Combustion and Flame   149 ( 1/2 )   144 - 161   2007年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    主要雑誌 代表的研究業績

  • Mass Transfer around a Cold Cylinder with Condensation of Vapor (1st Report)-Mass Flux Decrease due to Condensation of Vapor at Surface Temperatures from 200 to 250 K- 査読有り

    Fukiba,K.,Sato,T.,Tsuboi,N.,Kobayashi,H.

    Transactions of the Japan Society for Aeronautical and Space Sciences   50 ( 169 )   151 - 159   2007年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Numerical Study on Spinning Detonations 査読有り

    Tsuboi,N.,Hayashi,A.K.

    Proceedings of the Combustion Institute   31   1289 - 1296   2007年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 酸水素反応を伴うベル型ノズルの数値解析および性能評価 査読有り

    坪井伸幸,伊藤隆,宮島博

    日本航空宇宙学会論文集   54 ( 633 )   441 - 447   2006年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Interaction between Shock Wave and Boundary Layer in Nonequilibrium Hypersonic Rarefied Flow (5th Report, Nonequilibrium of Rotational Temperature in Flow over Flat Plate) 査読有り

    Tsuboi,N.,Matsumoto,Y.

    JSME International Journal   49 ( 3 )   771 - 779   2006年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Precooled Turbojet Engine Flight Experiment Using Balloon-Based Operation Vehicle 査読有り

    Fujita,K.,Sawai,S.,Kobayashi,H.,Tsuboi,N.,Taguchi,H. ,Kojima,T.,Okai,K.,Sato,T.,Miyaji,K

    Acta Astronautica   59 ( 1-5 )   263 - 270   2006年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • デトネーション駆動型衝撃風洞を用いたスクラムジェット燃焼器モデル内の燃焼過程 査読有り

    小原哲郎,伊藤豪明,金泰煥,大八木重治,坪井伸幸

    日本機械学会論文集B編   72 ( 718 )   1596 - 1604   2006年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • 冷却円柱周りの水蒸気の凝縮を含む流れの物質伝達(第2報)表面温度120250Kにおけるミストの付着を伴う物質伝達 査読有り

    吹場活佳,佐藤哲也,坪井伸幸,小林弘明

    日本航空宇宙学会誌論文集   54 ( 629 )   257 - 265   2006年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Numerical Simulation on Hydrogen Fuel Jetting from High Pressure Tank 査読有り

    Yun-Feng LIU,Hiroyuki SATO,Nobuyuki TSUBOI,Fumio HIGASHINO,A. Koichi HAYASHI

    Science and Technology of Energetic Materials   67 ( 1 )   7 - 11   2006年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Three-dimensional Chapman-Jouguet Detonation in a Rectangular Tube Effect of Cross-section Area- 査読有り

    Tsuboi,N.,Eto,K.,Hayashi,A.K

    Pulse and Continuous Detonation Propulsion   61 - 68   2006年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Experimental and Numerical Study on Shock Wave-Boundary Layer Interactions in Hypersonic Rarefied Gas Flow over a Flat Plate with Sharp Leading Edge 査読有り

    Tsuboi,N.,Matsumoto,Y

    AIAA Journal   43 ( 6 )   1243 - 1255   2005年06月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 冷却円柱周りの水蒸気の凝縮を含む流れの物質伝達(第1報)表面温度200250Kにおける水蒸気の凝縮による質量流束の低下 査読有り

    吹場活佳,佐藤哲也,坪井伸幸,小林弘明

    日本航空宇宙学会誌論文集   53   577 - 585   2005年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Numerical Study on Three-Dimensional C-J Detonation Waves:Detailed Propagating Mechanism and Existence of OH Radical 査読有り

    Eto,K.,Tsuboi,N.,Hayashi,A.K.

    Proceedings of the Combustion Institute 30, The Combustion Institute   30   1907 - 1913   2005年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • 希薄領域における極超音速非平衡流中の衝撃波と境界層干渉(第5報、平板上の非平衡な回転温度の計測とその評価) 査読有り

    坪井伸幸,松本洋一郎

    日本機械学会論文集B編   71 ( 702 )   46 - 53   2005年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • 希薄領域における極超音速非平衡流中の衝撃波と境界層干渉(第4報、希薄風洞用ノズルの設計) 査読有り

    坪井伸幸,松本洋一郎

    日本機械学会論文集B編   71 ( 706 )   1579 - 1587   2005年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Experimental and Numerical Studies on Detonation Wave Propagating in a Rectangular Tube with Obstacles 査読有り

    Sato,H.,Tsuboi,N.,Hayashi,A.K.,Lee,JHS

    Science and Technology of Energetic Materials, 日本火薬学会   65 ( 5 )   155 - 160   2004年09月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Three-Dimensional Direct Simulation Monte Carlo Method of Hypersonic Rarefied Gas Flow around a Sharlp Flat Plate 査読有り

    Tsuboi,N.,Yamaguchi,H.,Matsumoto,Y.

    Journal of Spacecraft and Rockets   41 ( 3 )   397 - 405   2004年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Experimental and Numerical Estimation of Pulse Detonation Engine Performance 査読有り

    Tsuboi,N.,Fujii,K,Kenmoku,Y.,Hayashi,A.K.

    Confined Detonation and Pulse Detonation Engines   249 - 260   2003年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Visualization of Jet Flows over a Plate by Pressure Sensitive Paint Experiments and Comparison with CFD 査読有り

    Fujii,K.,Tsuboi,N.,Fujimatsu,N.

    Visualization and Imaging Transport Phenomena, Annuals of the New York Academy of Sciences   972   265 - 270   2002年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 希薄領域における極超音速非平衡流中の衝撃派/境界層干渉 (第2報、並進/回転エネルギーの微視的状態の比較) 査読有り

    坪井伸幸,山口浩樹,松本洋一郎

    日本機会学会論文集B編   68 ( 670 )   1653 - 1660   2002年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • 希薄領域における極超音速非平衡流中の衝撃派/境界層干渉 (第3報、面分子干渉モデルの影響) 査読有り

    坪井伸幸,松本洋一郎

    日本機会学会論文集B編   68 ( 670 )   1661 - 1668   2002年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Three-Dimensional Numerical Simulation for Hydrogen/Air Detonation : Rectangular and Diagonal Structures 査読有り

    Tsuboi,N.,Katoh,S.,Hayashi A.K.

    Proceedings of the Combustion Institute, The Combustion Institute   29   2783 - 2788   2002年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 三次元デトネーションの数値解析 査読有り

    林光一,加藤誠司,坪井伸幸

    プラズマ応用科学,プラズマ応用科学会   9   149 - 153   2001年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Structure of Cornstarch-Oxygen Two-Phase Detonation in a Circular Tube 査読有り

    Tsuboi,N.,Hayashi,A.K.,Matsumoto,Y.

    Chemical Physics Reports(The Journal of the Russian academy of Sciences)   20 ( 6 )   56 - 66   2001年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Three-Dimensional Structure of Cornstarch-Oxygen Two-Phase Detonation in a Circular Tube 査読有り

    Tsuboi,N.,Hayashi,A.K.,Matsumoto,Y.

    Aachivum Combustionis   21 ( 2 )   101 - 116   2001年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Multi-Scale Analysis of Non-Equilibrium Hypersonic Rarefied Gas Flow 査読有り

    Matsumoto,Y.,Tsuboi,N.,Tokumasu,T. ,Yamanishi,N.

    Computational Fluid Dynamics Journal   9 ( 1-Ⅰ )   459 - 470   2001年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 希薄領域における極超音速非平衡流中の衝撃波/境界層干渉(第1報.連続体モデル及びLarsen-Borgnakkeモデルとの比較) 査読有り

    坪井伸幸,山口浩樹,松本洋一郎

    日本機械学会論文集(B編)   66 ( 646 )   1377 - 1386   2000年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Three-dimensional Parallel Simulation of Cornstarch-Oxygen Two-Phase Detonation 査読有り

    Tsuboi,N.,Hayashi,A.K.,Matsumoto,Y.

    Shock Waves   10 ( 4 )   277 - 285   2000年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Non-Equilibrium Hypersonic Diatomic Molecular Flow Simulation by DSMC Method 査読有り

    Matsumoto,Y.,Tsuboi,N.,Tokumasu,T.,Yamanishi,N.

    Modeling and Simulation based Engineering   1   893 - 898   1998年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • 平板に衝突する超音速噴流に関する数値解析及び実験 査読有り

    坪井伸幸,林光一,藤原俊隆,嵐和夫,児玉優

    日本航空宇宙学会誌   46 ( 536 )   485 - 496   1998年04月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)

  • Numerical Simulation of a Supersonic Jet Impingement on a Ground 査読有り

    Tsuboi,N.,Hayashi,A.K.,Fujiwara,T.,Arashi,K.,Kodama,Y.

    SAE 1991 Transactions, Journal of Aerospace Section 1   2   2168 - 2180   1991年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

▼全件表示

著書

  • Detonation Control for Propulsion : Pulse Detonation and Rotating Detonation Engine

    Piotr Wolański, Sergey Frolov, Kailas Kailasanath, Fred Schauer, Matthew Fotia, Christopher Brophy, Frank Lu, Kenneth Yu, Jiro Kasahara, Nobuyuki Tsuboi, Ken Matsuoka, Francois Falempin, Bruno Le Enaour, Jeong-Yeol Choi, Jian-Ping Wang, Boo Cheong Khoo, Chiang Juay Teo, Jiun-Ming Li(共著)

    Springer  2018年01月 

     詳細を見る

    記述言語:英語

  • 機械工学基礎課程 熱力学

    松村他(共著)

    朝倉書店  2015年08月  ( ISBN:978-4-254-23794-8

     詳細を見る

    記述言語:日本語

  • デトネーションの熱流体力学1

    デトネーション研究会編(共著)

    理工図書  2011年07月 

     詳細を見る

    記述言語:日本語

  • 計算力学ハンドブックシリーズ第Ⅲ巻「原子/分子・離散粒子のシミュレーション」

    松本洋一郎ほか(共著)

    日本機械学会  2009年07月 

     詳細を見る

    記述言語:日本語

口頭発表・ポスター発表等

  • 強度可変酸化剤流旋回型ハイブリッドロケットにおける酸化剤軸・接線噴射の非定常数値解析

    後藤 祥太, 小澤 晃平, 宇崎 友規, 西川 佳希, 坪井 伸幸

    日本機械学会九州支部講演論文集 

     詳細を見る

    開催期間: 2018年01月   記述言語:日本語  

    CiNii Article

  • 加速度環境におけるワックス燃料の境界層燃焼可視化実験へ向けた着火方法の検討

    吉野 拓郎, 小澤 晃平, 坪井 伸幸

    日本機械学会九州支部講演論文集 

     詳細を見る

    開催期間: 2018年01月   記述言語:日本語  

    CiNii Article

  • 二成分Lennard-Jones流体における対応状態原理の成立性

    髙橋 竜二, 坪井 伸幸, 徳増 崇, 津田 伸一

    日本機械学会九州支部講演論文集 

     詳細を見る

    開催期間: 2018年01月   記述言語:日本語  

    CiNii Article

  • 酸水素混合系の音速に対する古典的混合則の精度検証

    髙橋 竜二, 坪井 伸幸, 徳増 崇, 津田 伸一

    年次大会 

     詳細を見る

    開催期間: 2018年01月   記述言語:日本語  

    <p>In the computational fluid dynamics (CFD) analyses for the combustion chamber of typical liquid rocket engine, for the prediction of thermophysical properties of mixture system, classical mixing rule (CMR) is applied to cubic equation of state (EOS) for single-component. However, the validation of CMR has been hardly conducted because of few experimental data. Therefore, we have conducted the validation of CMR coupled with the Soave–Redlich–Kwong (SRK) EOS as one of the cubic EOSs for the sound speed of oxygen-hydrogen mixture system in supercritical state using molecular dynamics (MD) simulation with the NVEPG ensemble. We have validated the accuracy of CMR through the comparison of the sound speed obtained by MD simulations with that obtained by CMR coupled with the SRK EOS. As a result, we confirmed that the sound speed obtained from SRK EOS coupled with CMR corresponded with that obtained from MD simulations. Further, the relative difference in sound speed between the MD simulations and SRK EOS hardly increased against single-component fluids. This result indicates that the CMR can be applied for the sound speed of oxygen–hydrogen mixture system in supercritical condition.</p>

    CiNii Article

  • 実験によるCH<sub>4</sub>/O<sub>2</sub>デトネーションの伝播限界に当量比が与える影響の調査

    井上 卓, 吉田 啓祐, 森井 雄飛, 村上 清人, 坪井 伸幸, 林 光一

    日本機械学会九州支部講演論文集 

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    開催期間: 2017年01月   記述言語:日本語  

    CiNii Article

  • 再使用観測ロケットの空力特性に関する数値解析及び風洞試験

    西川 佳希, 牟田 智幸, 坪井 伸幸, 伊藤 隆, 野中 聡

    日本機械学会九州支部講演論文集 

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    開催期間: 2017年01月   記述言語:日本語  

    CiNii Article

  • 二次元数値解析によるローテーティングデトネーションエンジンの内部流れ場の解明:非理想形噴射口の影響調査

    塚本 真章, 江藤 成一朗, 坪井 伸幸, 小島 孝之, 林 光一

    日本機械学会九州支部講演論文集 

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    開催期間: 2017年01月   記述言語:日本語  

    CiNii Article

  • オービターを搭載したWaveriderの空力特性に関する数値解析及び風洞試験

    宇崎 友規, 牟田 智幸, 坪井 伸幸, 丸 祐介, 藤田 和央

    日本機械学会九州支部講演論文集 

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    開催期間: 2017年01月   記述言語:日本語  

    CiNii Article

  • Mixing Characteristics of a Recessed Coaxial Jet at Supercritical Pressure

    Daiki Muto, Hiroshi Terashima, Nobuyuki Tsuboi

    AIAA SciTech2016 

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    開催期間: 2016年01月   記述言語:英語  

  • 高圧水素噴流の拡散過程の3次元数値解析

    藤本 啓佑, 武藤 大貴, 坪井 伸幸, 朝原 誠

    流体工学部門講演会講演論文集 

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    開催期間: 2016年01月   記述言語:日本語  

    <p>Three-dimensional numerical simulation of high pressure hydrogen jet is performed. Hydrogen leakage from the high pressure hydrogen tank has a possibility of serious explosion accidents. Therefore, it is necessary to understand diffusion behavior and ignition characteristics of hydrogen leakage. The present study simulates the high-pressure hydrogen supersonic free jet into the atmosphere to understand the dispersion process. As a result, the Jet flow fluctuates greatly in the radial direction and hydrogen disperses in a wide sphere. Also, lambda vortex structure was found to perform a crucial function in the diffusion of hydrogen.</p>

    CiNii Article

  • 液体燃料ロケットタンク破壊時の推進剤ジェット・主流の干渉メカニズムに関する数値解析

    岩佐 聡洋, 武藤 大貴, 藤本 圭一郎, 坪井 伸幸

    年次大会 

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    開催期間: 2016年01月   記述言語:日本語  

    <p>Numerical simulations of the jet injected into supersonic cross-flow are carried out. In aborting process in liquid rocket flight, the fuel is transversely injected into the supersonic freestream. Developed jet/freestream interaction structure may trigger unexpected auto-ignition or explosion events; thus the understanding of the flow-field of jet-in-supersonic cross-flow is essential to meet the reliability of rocket. The two-dimensional numerical simulations are carried out in a wide-range of jet and freestream conditions: the jet-to-freestream momentum flux ratio and the pressure ratio. Present result shows recirculation regions are formed both at the upstream and downstream of injector with the characteristic vortex structures. With increasing the jet-to-freestream momentum flux ratio, the vortex structures in the recirculation region are largely developed. It is founded that the highest temperature in the separation region depends on the total temperature in the separation region and furthermore, it is the lower temperature than the total temperature of freestream.</p>

    CiNii Article

  • Aerodynamic Characteristics Study on Waverider for Applying to TSTO

    Tomoyuki Muta, Haruka Etoh, Nobuyuki Tsuboi, Yusuke Maru, Kazuhisa Fujita

    30th International Symposiumon Space Technokigy and Science 

     詳細を見る

    開催期間: 2015年06月   記述言語:英語  

  • Characteristics of Jet-Mixing at Supercritical Pressure for Coaxial Rocket Injector Design

    Daiki Muto, Nobuyuki Tsuboi, Hiroshi Terashima

    30th International Symposiumon Space Technokigy and Science 

     詳細を見る

    開催期間: 2015年06月   記述言語:英語  

  • Evaluation of Thrust Performance on Rotating Detonation Engine for a JP10-Air Mixture

    Wataru Yoshida, Makoto Asahara, Nobuyuki Tsuboi, A.Koichi Hayashi

    30th International Symposiumon Space Technokigy and Science 

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    開催期間: 2015年06月   記述言語:英語  

  • Effects of the Recess Length on Supercritical Jet Mixing of Co-planar/axial Injectors

    Daiki Muto, Nobuyuki Tsuboi, Hiroshi Terashima

    6th European Conference forAeronautics and Space Sciences(EUCASS 2015) 

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    開催期間: 2015年06月   記述言語:英語  

  • Effects of Injector Geometry on Co-Flowing Planar Jet Mixings under Supercritical Pressures

    Daiki Muto, Nobuyuki Tsuboi, Hiroshi Terashima

    AIAA SciTech2015 

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    開催期間: 2015年01月   記述言語:英語  

  • Numerical simulation of thrust performance estimation on rotating detonation engine : The effects of nozzle on Isp

    Yusuke WATANABE, Seiichiro ETOH, Nobuyuki TSUBOI, Takayuki KOJIMA, A. Koichi HAYASH

    The 5th International symposium on Energetic Materials and their applications 

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    開催期間: 2014年11月   記述言語:英語  

  • Interaction between Shock Wave and Spherical Flme in Ethylene/Air Mixture and Transition to Detonation

    Takayuki Araki, Youhi Morii, Nobuyuki Tsuboi, Koichi A. Hayashi

    The 5th International symposium on Energetic Materials and their applications 

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    開催期間: 2014年11月   記述言語:英語  

  • Near propagation limit behavior of CH4/O2 Detonation in round tube:influence of equivalent ratio and tube diameter

    Keisuke Yoshida, Koichi Hayashi, Youhi Morii, Kiyoto Murakami, Akio Susa, Nobuyuki Tsuboi A. Koichi Hayash

    The 5th International symposium on Energetic Materials and their applications 

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    開催期間: 2014年11月   記述言語:英語  

  • Numerical Simulation on Unsteady Compressible Low-Speed Shear Flow in Hybrid Rocket Combustion Chamber Using Preconditioned Method: Effects of Preconditioned Method Including Multi-Species Mass Conservation Equations

    Nobuyuki Tsuboi

    Eleventh International Conference on Flow Dynamics 

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    開催期間: 2014年10月   記述言語:英語  

  • Numerical study of cryogenic coaxial jet under supercritical condition

    Muto D., Tsuboiy N., Terashimaz H.

    52nd AIAA Aerospace Sciences Meeting - AIAA Science and Technology Forum and Exposition, SciTech 2014 

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    開催期間: 2014年01月01日   記述言語:英語  

    Effects of recess on the mixing of the cryogenic coaxial jet under supercritical conditions were numerically investigated. Recessed injectors have been applied as coaxial injectors of liquid rocket engines because it is expected to improve propellant mixing and combustion efficiency. In the present study, a numerical simulation code was developed to examine jet mixing under the supercritical pressures. For validation of the present method, a two-dimensional planner jet simulation was carried out. The present result showed good agreement with an experimental result. As a preliminary study of coaxial jets, co-planner simulations were performed in a recessed case and an unrecessed case. Large-scale vortical structures were observed in the both cases, and the recessed case showed the larger struc- tures relative to the unrecessed case. This is because of the destabilization mechanism of a recessed region. These instabilities improved entrainments of ambient uid, and as a result, the enhanced jet mixing shortens the jet-core length.

  • Numerical Study of Cryogenic Coaxial Jet under Supercritical Condition

    D. Muto, N. Tsuboi, H. Terashima

    AIAA SCITECH2014 

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    開催期間: 2014年01月   記述言語:英語  

  • Numerical Simulation on Unsteady Compressible Low-Speed Flow Using Preconditioning Method: Preconditioning Method Including Multi-Species Mass Conservation Equations

    Nobuyuki Tsuboi

    Tenth International Conference on Flow Dynamics 

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    開催期間: 2013年11月   記述言語:英語  

  • Detailed Investigation on the Wave Structures in Ethylene/Oxygen Detonations in Narrow Channels

    T. Araki, Y. Morii, N. Tsuboi, A.K. Hayashi

    9th International High Energy Materials 

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    開催期間: 2013年10月   記述言語:英語  

  • Numerical Analysis of Spinning Detonation Dependency on Initial Pressure Using AUSMDV Scheme

    Tsuyoshi Nagao, Makoto Asahara, A. Koichi Hayashi, Nobuyuki Tsuboi, Eisuke Yamada

    51th AIAA Aerospace Sciences Meeting 

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    開催期間: 2013年01月   記述言語:英語  

  • Three-dimensional Numerical Simulation on Unsteady Compressible Flow Using Preconditioning Method in Hybrid Rocket Engine: Effects of Preconditioning Schemes

    N.Tsuboi, K.Fukiba, T.Shimada

    Ninth International Conference on Flow Dynamics (ICFD2012) 

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    開催期間: 2012年09月   記述言語:英語  

  • メタン酸素及び水素酸素燃料を用いた狭い管内を伝播する爆轟波の二次元数値解析

    森井雄飛, 坪井伸幸, 小川博之, 寺島洋史, 徳留真一郎, 林光一

    平成23年度衝撃波シンポジウム,1B2-4, 2012.3 

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    開催期間: 2012年03月   記述言語:日本語  

  • 重み付きコンパクトスキームを用いた2次元デトネーションの数値解析:高解像度スキームによる流れ場の詳細構造

    坪井伸幸, 朝原誠, 野々村拓, 林光一

    平成23年度衝撃波シンポジウム,1B2-6, 2012.3 

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    開催期間: 2012年03月   記述言語:日本語  

  • 2次元円筒デトネーションにおけるSub TransverseWaveの発生と発達

    朝原誠, 林光一, 山田英助, 坪井伸幸

    平成23年度衝撃波シンポジウム,1B2-6, 2012.3. 

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    開催期間: 2012年03月   記述言語:日本語  

  • 水素/空気デトネーションにおける反応モデルの影響の評価

    杉安孝幸, 森井雄飛, 坪井伸幸, 林光一

    平成23年度衝撃波シンポジウム,3B2-5, 2012.3. 

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    開催期間: 2012年03月   記述言語:日本語  

  • 低Re数における前処理型非定常圧縮性流れ場解析によるNACA0012翼型の空力特性評価

    村田健輔, 坪井伸幸, 吹場活佳, 嶋田徹

    日本機械学会九州学生会(2012) 第43回学生員卒業研究発表講演会, 439, 2012.3 

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    開催期間: 2012年03月   記述言語:日本語  

  • LESによる超臨界流体噴流の流体力学的挙動に関する数値解析

    瀬戸口,武藤,寺島,坪井,越

    日本機械学会九州学生会(2012) 第43回学生員卒業研究発表講演会, 434, 2012.3 

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    開催期間: 2012年03月   記述言語:日本語  

  • 前処理型非定常圧縮性解法による噴流構造の数値解析

    武藤大貴,瀬戸口彬,寺島洋史,坪井伸幸,越光男

    日本機械学会 九州支部第65期総会・講演会,803, 2012.3. 

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    開催期間: 2012年03月   記述言語:日本語  

  • 数値解析を用いたエアロスパイクノズルの性能評価:圧力比の影響

    成宮匡,坪井伸幸,伊藤隆

    日本機械学会 九州支部第65期総会・講演会,812, 2012.3. 

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    開催期間: 2012年03月   記述言語:日本語  

  • 極超音速流れにおける30°ランプ周りの流れ場の3次元数値解析:平板幅の影響

    倉本健史,武藤大貴,坪井伸幸,永井大樹( 東北大),浅井圭介

    日本機械学会 九州支部第65期総会・講演会,812, 2012.3. 

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    開催期間: 2012年03月   記述言語:日本語  

  • Three-Dimensional Numerical Simulation on Unsteady Compressible Flow Using Preconditioning Method: Swirling Injector Flowfield in Hybrid Rocket Engine

    Nobuyuki Tsuboi, Katsuyoshi Fukiba, Toru Shimada

    Eighth International Conference on Flow Dynamics (ICFD2011),OS5-15(pp.312-313) 

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    開催期間: 2011年11月   記述言語:英語  

  • Lewis number effect on DDT process and detonation

    E. Dzieminska, A. K. Hayashi, N. Tsuboi

    The 4th International Symposium on Energetic Materials and their Applications, 16-B1-4, 2011.11 

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    開催期間: 2011年11月   記述言語:英語  

  • Numerical approach to one-dimensional CH4/O2 detonation with the reduction model DRG30

    Youhi Morii, Nobuyuki Tsuboi, Hiroyuki Ogawa,Shinichiro Tokudome, and A. Koichi Hayashi

    The 4th International Symposium on Energetic Materials and their Applications, 17-A1-1, 2011.11 

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    開催期間: 2011年11月   記述言語:英語  

  • Three-dimensional simulation on a rotating detonation engine: Three-dimensional shock structure

    N. Tsuboi, T. Yamada, A. K. Hayashi, E. Yamada

    The 4th International Symposium on Energetic Materials and their Applications, 18-H-2, 2011 

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    開催期間: 2011年11月   記述言語:英語  

  • A Molecular Study on the Thermodynamic Properties of Cryogenic Hydrogen

    Hiroki Nagashima, Takashi Tokumasu, Shinichi Tsuda, Nobuyuki Tsuboi and A. Koichi Hayashi

    Seventh International Conference on Flow Dynamics, CRF-39, 2010 

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    開催期間: 2010年11月   記述言語:英語  

  • Numerical simulation of a bio-fuel/air two-phase detonation -propagation mechanism using ethanol-

    T. Shimada, A.K. Hayashi, E. Yamada N. Tsuboi

    Eighth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions, ISH103, 2010 

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    開催期間: 2010年09月   記述言語:英語  

  • Computational study on cell bifurcation in two-dimensional cylindrical detonation using AUSMDV scheme

    M. Asahara, N. Tsuboi, A.K. Hayashi E.Yamada

    Eighth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions, ISH105, 2010 

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    開催期間: 2010年09月   記述言語:英語  

  • Three-dimensional simulations of H2/O2 detonation in a round bent tube

    N. Tsuboi, A.K. Hayashi, M. Uchida, T. Fujimori

    Eighth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions, ISH106, 2010 

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    開催期間: 2010年09月   記述言語:英語  

  • The effects of the schemes in inviscid flux on spinning detonation in a round tube

    Y. Morii, M. Asahara, N. Tsuboi, A.K. Hayashi, M. Koshi, H. Ogawa, S. Tokudome

    Eighth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions, ISH101, 2010 

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    開催期間: 2010年09月   記述言語:英語  

  • The Molecular Simulation of Cryogenic Hydrogen Using Classical Method

    Hiroki Nagashima, Takashi Tokumasu, Shin-ichi Tsuda, Nobuyuki Tsuboi, Mitsuo Koshi, A. Koichi Hayashi

    1st IUPAC International Conference on Chemical Thermodynamics, ICCT2010-TS-3200-1740, 2010 

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    開催期間: 2010年08月   記述言語:英語  

  • Construction of a reliable reduced CH4/O2 chemical reaction model under high pressure states

    Youhi Morii, Nobuyuki Tsuboi, Mitsuo Koshi, Hiroyuki Ogawa,A. Koichi Hayashi, Taro Shimizu

    AJCPP2010-084, Asian Joint Conference on Propulsion and Power 2010, Miyazaki, 2010.3 

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    開催期間: 2010年03月   記述言語:英語  

  • Nonintrusive Diagnostics of Distribution of AP Particles in Composite Propellants

    Hiroshi Hasegawa,Kazushige Kato, Hideo Miyachi, Mihoko Fukunaga,Nobuyuki Tsuboi, Yuzou Yajima,Katsumi Hiraoka,Yu Daimon,Toru Shimada

    AJCPP2010-115, Asian Joint Conference on Propulsion and Power 2010, Miyazaki, 2010 

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    開催期間: 2010年03月   記述言語:英語  

  • Advanced Computer Science on Internal Ballistics of Solid Rocket Motors: 2009 Progress Report

    Toru Shimada, Kazushige Kato, Nobuhiro Sekino, Nobuyuki Tsuboi,Hiroshi Hasegawa, Mihoko Fukunaga, Yu Daimon, Hiroya Asakawa

    AJCPP2010-117, Asian Joint Conference on Propulsion and Power 2010, Miyazaki, 2010.3 

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    開催期間: 2010年03月   記述言語:英語  

  • Numerical Simulation on Unsteady Compressible Low-Speed Flow Using Preconditioning Method: Comparison between AUSMDV and AUSM+-up

    Nobuyuki Tsuboi, Katsuyoshi Fukiba, Toru Shimada

    AJCPP2010-088, Asian Joint Conference on Propulsion and Power 2010, Miyazaki, 2010.3 

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    開催期間: 2010年03月   記述言語:英語  

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講演

  • Numerical Study on Detonation and Rotating Schemes for Hydrocarbon Fuel

    10th International Workshop on Detonation for Propulsion  2019年09月 

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    発表言語:英語   講演種別:招待講演   開催地:Saint Petersburg, Russia  

  • Numerical Study of Detonation and Rotating Detonation Engine : Effects of Aerospike Nozzle on Thrust Performance and Recent Higher-order Simulations

    2018 International Workshop on Detonation for Propulsion  2018年09月 

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    講演種別:招待講演  

  • デトネーションの数値シミュレーション:基礎研究からデトネーションエンジンまで

    平成29年度宇宙輸送シンポジウム  2018年01月 

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    講演種別:特別講演  

  • Two-dimensional Numerical Simulation on Rotating Detonation Engine: Effects of Multi-port Injection

    International Constant Volume and Detonation Combustion Workshop 2017  2017年07月 

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    講演種別:招待講演  

  • Simulation on Rotating Detonation Engine: Effects of Converging-Diverging Nozzle, Non-uniform Injection, and Hydrocarbon-fueled Detonation

    2016 International Workshop on Detonation for Propulsion  2016年07月 

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    講演種別:招待講演  

  • Numerical Simulation on Rotating Detonation Engine : Effects of Higher-Order Scheme and Converging-Diverging Nozzle

    2015 International Workshop on Detonation for Propulsion  2015年08月 

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    講演種別:招待講演   開催地:Beijing, China  

  • Numerical Study on a Rotating Detonation Engine at KIT

    2013 International Workshop on Detonation for Propulsion  2013年07月 

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    講演種別:招待講演   開催地:Tainan, Taiwan  

  • Numerical Simulation on a Rotating Detonation Engine: Evaluation of Thrust Performance

    International Workshop on Detonation for Propulsion 2012  2012年09月 

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    講演種別:招待講演   開催地:筑波  

  • Numerical Simulations on Pulse Detonation Engines and Rotating Detonation Engines with Nozzles2011 International Workshop on Detonation for Propulsion

    2011 International Workshop on Detonation for Propulsion  2011年11月 

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    講演種別:招待講演   開催地: 釜山,韓国  

  • 酸水素反応を伴うベル型ノズルの数値解析及び性能評価

    日本航空宇宙学会第39期講演会,2008(論文賞受賞講演)  2008年04月 

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    講演種別:招待講演  

  • Numerical Apploach on Hydrogen Detonation : Fundamentals and Applications

    The Second European Summer School on Hydrogen Safety  2007年08月 

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    講演種別:招待講演  

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学術関係受賞

  • best presentation award

    4th International Symposium on Energetic Materials and their Applications   2011年11月

    N.Tsuboi, T.Yamada, A.K.Hayashi, E.Yamada

     詳細を見る

    受賞国:日本国

科研費獲得実績

  • 同軸噴射器形状が極低温高圧推進剤の混合拡散燃焼過程へ及ぼす影響の解明

    研究課題番号:15H04202  2015年04月 - 2018年03月   基盤研究(B)

  • 極低温超臨界流体における燃焼ダイナミクスの研究

    研究課題番号:23360380  2011年04月 - 2014年03月   基盤研究(B)

担当授業科目(学内)

  • 2023年度   自動車工学特論Ⅱ

  • 2023年度   自動車工学特論Ⅰ

  • 2023年度   高速気体力学特論

  • 2023年度   数値流体力学特論

  • 2023年度   機械工学実験Ⅰ

  • 2023年度   燃焼工学

  • 2023年度   圧縮性流体力学

  • 2023年度   宇宙システム工学入門

  • 2023年度   圧縮性流体力学

  • 2023年度   流体力学基礎

  • 2023年度   燃焼工学

  • 2023年度   機械工学実験Ⅱ

  • 2023年度   機械工学実験Ⅰ

  • 2023年度   機械工学実験Ⅰ

  • 2022年度   自動車工学特論Ⅱ

  • 2022年度   自動車工学特論Ⅰ

  • 2022年度   高速気体力学特論

  • 2022年度   数値流体力学特論

  • 2022年度   燃焼工学

  • 2022年度   圧縮性流体力学

  • 2022年度   宇宙システム工学入門

  • 2022年度   圧縮性流体力学

  • 2022年度   流体力学基礎

  • 2022年度   燃焼工学

  • 2021年度   高速気体力学特論

  • 2021年度   数値流体力学特論

  • 2021年度   燃焼工学

  • 2021年度   圧縮性流体力学

  • 2021年度   圧縮性流体力学

  • 2021年度   流体力学基礎

  • 2021年度   燃焼工学

  • 2020年度   高速気体力学特論

  • 2020年度   数値流体力学特論

  • 2020年度   燃焼工学

  • 2020年度   圧縮性流体力学

  • 2020年度   圧縮性流体力学

  • 2020年度   流体力学基礎

  • 2020年度   燃焼工学

  • 2019年度   高速気体力学特論

  • 2019年度   数値流体力学特論

  • 2019年度   流体力学基礎

  • 2019年度   熱流体工学

  • 2018年度   数値流体力学特論

  • 2018年度   高速気体力学特論

  • 2018年度   流れ学基礎

  • 2018年度   熱流体工学

  • 2017年度   高速気体力学特論

  • 2017年度   数値流体力学特論

  • 2017年度   流れ学基礎

  • 2017年度   機械知能工学入門

  • 2017年度   機械知能工学概論

  • 2016年度   流れ学基礎

  • 2016年度   機械知能工学入門

  • 2016年度   機械知能工学概論

  • 2016年度   高速気体力学特論

  • 2016年度   数値流体力学特論

  • 2015年度   数値流体力学特論

  • 2015年度   高速気体力学特論

  • 2015年度   流れ学基礎

  • 2014年度   流れ学基礎

  • 2014年度   数値流体力学特論

  • 2014年度   高速気体力学特論

  • 2013年度   数値流体力学特論

  • 2013年度   流れ学基礎

  • 2012年度   高速気体力学特論

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  • 2012年度   流れ学基礎

  • 2011年度   高速気体力学特論

  • 2011年度   数値流体力学特論

  • 2011年度   流れ学基礎

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