Faculty Profiles - TSUBOI Nobuyuki

Papers - TSUBOI Nobuyuki

Division display1 - 20 of about 254／ All the affair displays >>

Investigation of liquid n-heptane/air spray detonation with an Eulerian-Eulerian model Reviewed International journal

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

Combustion and Flame 244 2022.10

Effects of a Recess on Coaxial Cryogenic Injections at Supercritical Pressure Reviewed International journal

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

Journal of Propulsion and Power 38 ( 4 ) 581 - 591 2022.01

Difference between 2D and 3D NS calculations for RDE pressure gain Reviewed International journal

Hayashi A.K., Nihonmatsu R., Ito T., Tsuboi N., Ozawa K., Otsuka Y., Ishii K.

AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025 2025.01

Correction: [3D Numerical Simulation on Disk Type RDE used Hydrogen-Air Premixed Gas and Non-premixed Gas with Multi-Ports Injection] (American Institute of Aeronautics and Astronautics Inc, AIAA) Reviewed International journal

Ito T., Tsuboi N., Ozawa K., Hayashi A.K.

AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025 2025.01

3D Numerical Simulation on Disk Type RDE used Hydrogen-Air Premixed Gas and Non-premixed Gas with Multi-Ports Injection Reviewed International journal

Ito T., Tsuboi N., Ozawa K., Hayashi A.K.

AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025 2025.01

Two-dimensional detailed numerical simulation of ammonia/hydrogen/air detonation: hydrogen concentration effects and transverse detonation wave structure Reviewed International journal

Kohama S., Ito T., Tsuboi N., Ozawa K., Hayashi A.K.

Shock Waves 34 ( 2 ) 139 - 154 2024.04

Study of Nozzle Choking Effect on Pressure Gain of Disc Rotating Detonation Engine Reviewed International journal

Hayashi A.K., Otsuka Y., Ishii K., Ito T., Tsuboi N., Ozawa K.

AIAA SciTech Forum and Exposition, 2024 2024.01

Two-Dimensional Detailed Numerical Simulation on Ammonia/Hydrogen/Air Detonation : Hydrogen dilution effects and sub-transverse wave structure in transverse detonation Reviewed International journal

Shui Kohama, Nobuyuki Tsuboi, Kouhei Ozawa, Koichi A Hayashi

29th International Colloquium on the Dynamics of Explosions and Reactive Systems Papaer 176 2023.07

Analysis on Pressure Gain of Rotating Detonation Engine Reviewed International journal

A. K. Hayashi, Y. Otsuka, K. Ishii, K. Yoshidomi, T. Ito, N. Tsuboi, K. Ozawa

The 34th International Symposium on Shock Waves T04-0282 2023.07

Effects of Reynolds Number and Ramp Angle on Gortler Vortices over a Compression Ramp Reviewed International journal

Kalash Dixit, Ritu Raj Kumar, Nagabhushana Rao Vadlamani, Nobuyuki Tsuboi

The 34th International Symposium on Shock Waves T19-0135 2023.07

Numerical Simulation on DDT in Real and Large Scale Combustion Chamber Using a Combustion Velocity Model and Ignition Model with a Detailed Chemical Reaction System Reviewed

Ichiro Nakamori, Takayuki Tomizuka, Atsuo Takahashi, Fumitomo Onishi, Mikhail Kuznetsov, Takashi Kodama, Yoshikazu Tamauchi, Naoya Sato, A. Koichi Hayashi and Nobuyuki Tsuboi

29th International Colloquium on the Dynamics of Explosions and Reactive Systems Paper 127 2023.07

Detailed Numerical Simulation on Dimethyl Ether/Oxygen Premixture Detonation Using Reduced Chemical Reaction Model -Disturbance of Cellular Structure- Reviewed International journal

Kubota Daiki, Tsuboi Nobuyuki, Ozawa Kohei, Hahashi A. Koichi

29th International Colloquium on the Dynamics of Explosions and Reactive Systems Paper 193 2023.07

Operation characteristics of a disk-type rotating detonation engine Reviewed International journal

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

Shock Waves 33 ( 3 ) 267 - 274 2023.04

Influence of tube cross-section geometry on high-pressure hydrogen-flow-induced self-ignition Reviewed International journal

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

International Journal of Hydrogen Energy 48 ( 21 ) 7909 - 7926 2023.03

Numerical Study of Cryogenic Hydrogen Jet in Crossflow under Supercritical Pressure: Comparison of Tandem and Twin Jets Reviewed International journal

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

Journal of Evolving Space Activities ( International Symposium on Space Technology and Science ) 1 ( 0 ) n/a 2023.01

Language：English Publishing type：Research paper (scientific journal)

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.

DOI： 10.57350/jesa.29

CiNii Research

Visualization of the physical destruction process of additive-manufactured regression sensor structures Reviewed International journal

Ozawa Kohei, Neki Tomoya, Tsuboi Nobuyuki

Science and Technology of Energetic Materials ( Japan Explosives Society ) 84 ( 2 ) 24 - 31 2023.01

Authorship：Last author Language：English Publishing type：Research paper (scientific journal)

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

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 Reviewed International journal

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

Journal of Thermal Science and Technology ( The Japan Society of Mechanical Engineers and The Heat Transfer Society of Japan ) 18 ( 1 ) 22-00365 - 22-00365 2023.01

Language：English Publishing type：Research paper (scientific journal)

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

Other Link： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85145967290&origin=inward

3D Evaluation of Premixed Gas Injection Ports Number on Flow Field in Disk RDE Reviewed International journal

Ito T., Tsuboi N., Ozawa K., Hayashi A.K.

AIAA SciTech Forum and Exposition, 2023 2023.01

Numerical Study on Pressure Gain of Rotating Detonation System Reviewed International journal

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

AIAA SciTech Forum and Exposition, 2023 2023.01

Numerical study on unsteady characteristics of high-pressure hydrogen jet ejected from a pinhole Reviewed

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

International Journal of Hydrogen Energy 47 ( 74 ) 31709 - 31728 2022.08

　PREV- NEXT 　

<TSUBOI Nobuyuki>

Papers - TSUBOI Nobuyuki