研究者詳細 - 石原　大輔

その他リンク： https://ci.nii.ac.jp/naid/130008062974

炭素繊維複合材およびドライクロスの誘導加熱解析査読有り

中村俊太, 堀江知義, 二保知也, 石原大輔

日本AEM学会誌 ( 日本AEM学会 ) 29 ( 3 ) 576 - 582 2021年01月

記述言語：日本語掲載種別：研究論文（学術雑誌）

Heating analysis of CFRP and carbon fiber dry cloth for aircraft structures, which is expected for a medium-sized aircraft, is performed. Comparing the temperature of test pieces between numerical and experimental results, validity of both experimental and analytical methods is confirmed for both aluminum and carbon dry cloth sheet. Analysis is made for the layers of carbon dry cloth sheet and CFRTP plate.

DOI： 10.14243/jsaem.29.576

その他リンク： https://ci.nii.ac.jp/naid/130008142891

電気機械システムの圧電ー逆圧電ー構造連成現象に対する分離反復型解法に関する研究

相川昇壱, 石原大輔, 熊谷武尊, 岩丸直樹, プラカシャラメゴウダ, 大西南斗

計算力学講演会講演論文集 ( 一般社団法人日本機械学会 ) 2021.34 ( 0 ) 249 2021年01月

担当区分：責任著者記述言語：日本語掲載種別：研究論文（学術雑誌）

In micro-electro-mechanical systems using piezoelectric bimorph actuators such as FWNAV, small displacements given by the actuators can be magnified using a transmission using the flexible structure. Hence, in these systems, coupling among the direct and inverse piezoelectric effects, and the flexible structure occurs. In this study, a partitioned iterative method is proposed based on the block SUR algorithm for this strongly coupled problem, and the basic performances are demonstrated in numerical examples.

DOI： 10.1299/jsmecmd.2021.34.249

その他リンク： https://www.jstage.jst.go.jp/article/jsmecmd/2021.34/0/2021.34_249/_pdf

誘導加熱による炭素繊維複合材成形のための電磁場・熱伝導連成解析

二保知也, 中村俊太, 石原大輔, 堀江知義, 神原信幸, 志谷徹

計算力学講演会講演論文集 ( 一般社団法人日本機械学会 ) 2021.34 ( 0 ) 130 2021年01月

記述言語：日本語掲載種別：研究論文（学術雑誌）

Bonding and forming of carbon fiber reinforced plastic by induction heating are required for medium-sized aircraft manufacturing. In this paper, electromagnetic and thermal conduction coupled finite element analysis method is described for induction heating of carbon fiber dry cloth. Experiments of induction heating are also performed to discuss the validity of analysis method and experimental method. Comparing the temperature of test pieces between analysis and experimental results, validity of both methods is confirmed for both aluminum sheet and carbon fiber dry cloth.

DOI： 10.1299/jsmecmd.2021.34.130

その他リンク： https://www.jstage.jst.go.jp/article/jsmecmd/2021.34/0/2021.34_130/_pdf

昆虫羽ばたき翼の空力性能に対する受動的キャンバーの影響

大西南斗, 石原大輔

計算力学講演会講演論文集 ( 一般社団法人日本機械学会 ) 2021.34 ( 0 ) 176 2021年01月

担当区分：最終著者,　責任著者記述言語：日本語掲載種別：研究論文（学術雑誌）

Any shape change of insect’s wings during their flapping motion will be passively caused by external forces such as the inertial and aerodynamic forces because the wings have no interior muscle. The camber deformation, which is the focus of this study, plays an important role in the aerodynamic performance of the insect’s flapping flight. In this study, the effect of passive cambering is investigated using a fluid-structure interaction analysis and a pixel wing model using only structured shell elements, which adequately simulates the camber deformation in actual insects.

DOI： 10.1299/jsmecmd.2021.34.176

その他リンク： https://www.jstage.jst.go.jp/article/jsmecmd/2021.34/0/2021.34_176/_pdf

圧電エネルギーハーベスティングにおける構造−圧電−電気回路相互作用に対する連成アルゴリズムの比較検討

高山直人, 石原大輔, Prakasha Chigahalli Ramegowda, 大西南斗

計算力学講演会講演論文集 ( 一般社団法人日本機械学会 ) 2021.34 ( 0 ) 210 2021年01月

担当区分：責任著者記述言語：日本語掲載種別：研究論文（学術雑誌）

In recent years, energy harvesting from environment has attracted much attention. In particular, piezoelectric bimorph energy harvesters, which are effective as an energy source for MEMS, have been widely studied. In piezoelectric energy harvesters, structure, piezoelectricity, and circuit are strongly coupled in a complicated and hierarchical manner. For the three-field coupling phenomena, unlike two-field coupling phenomena, various partitioned algorithms are possible. Hence, in this study, we develop three partitioned algorithms using hierarchical decomposition: In the first algorithm, all fields are solved implicitly or strongly coupled using the block Gauss-Seidel (BGS) method (fully strong coupling algorithm). In the second algorithm, the structure-piezoelectric interaction is solved implicitly or strongly coupled using the BGS method, and the circuit is solved explicitly or weakly coupled (partially strong coupling algorithm). In the third algorithm, all fields are solved explicitly or weakly coupled (fully weak coupling algorithm). These methods are applied to a typical piezoelectric harvester, namely a cantilevered piezoelectric bimorph, and their performances such as the accuracy and the computational cost are discussed.

DOI： 10.1299/jsmecmd.2021.34.210

その他リンク： https://www.jstage.jst.go.jp/article/jsmecmd/2021.34/0/2021.34_210/_pdf

A Design Window Search Using Nonlinear Dynamic Simulation for Polymer Micro-machined Transmission in Insect-inspired Flapping wing Nano Air Vehicles 査読有り国際誌

Rashmikant , Ishihara D.

2021 6th International Conference on Robotics and Automation Engineering, ICRAE 2021 162 - 167 2021年01月

担当区分：最終著者,　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）

The novelty of this study is the proposition of a design window (DW) search using the nonlinear dynamic simulation, and the finding of the DWs of the polymer micro transmission that satisfies the nonlinear and unsteady design requirements conflicting with each other simultaneously. Here, the DW is defined as an existing area of satisfactory solutions in a design parameter space, which is defined as the flapping frequency equivalent to small flies and the mass of the micro wing supported by the transmission design. Since this micro transmission is the key component of the flapping wing nano air vehicle (FWNAVs) which has a 2.5-D structure and is fabricated using polymer micromachining so proposed DWs will contribute to further miniaturizing FWNAVs.

DOI： 10.1109/ICRAE53653.2021.9657802

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85124796665&origin=inward

HIERARCHICALLY DECOMPOSED FINITE ELEMENT METHOD FOR THE COUPLED FOUR FIELDS OF THE FLUID-STRUCTURE-PIEZOELECTRIC-CIRCUIT INTERACTION 査読有り国際誌

Ramegowda P.C., Ishihara D.

9th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2021 2021年01月

担当区分：最終著者,　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）

A partitioned iterative method based on hierarchical decomposition is proposed for providing numerical modeling and analysis of the piezoelectric energy harvester which is involved in coupled fluid-structure interaction, coupled electro-mechanical, and a controlling electrical circuit for piezoelectric structural applications in energy harvesting. This circuitintegrated piezoelectric structural application in energy harvesting surrounded by fluid media takes the form of natural four-way coupling of fluid flow, the structure, the electromechanical effect of the piezoelectric material, and the electrical circuit. This can be formulated exactly as a fluid-structure-piezoelectric-circuit interaction. These coupled four fields are hierarchically decomposed into the fluid-structure interaction, structure-piezoelectric interaction, and piezoelectric-circuit interaction interactions. Then these subsystems are decomposed into each field. The proposed finite element method enables to reuse of existing techniques because of its modularity. Furthermore, scalability to multiphysics and multisystem couplings is expected. There are some numerical approaches in particular monolithic coupling methods are studied which are computationally expensive and leads to an ill-conditioned coefficient matrix. Nevertheless, accurate modeling for predicting the characteristics of this four-way coupling using partitioned methods has not yet been developed. This method enables an investigation of piezoelectric structures in fluid with complex geometry, material composition, and attached electrical circuits to the harvester. A flexible piezoelectric bimorph harvester in the converging channel is analyzed to demonstrate the efficiency of the proposed method. The results indicate that the method captures the coupled effect accurately.

DOI： 10.23967/coupled.2021.031

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85206907959&origin=inward

COMPUTATIONAL FLUID-STRUCTURE INTERACTION FRAMEWORK FOR SIMULATING CHARACTERISTIC DEFORMATIONS IN INSECT FLAPPING WINGS 査読有り国際誌

Onishi M., Ishihara D.

9th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2021 2021年01月

担当区分：最終著者,　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）

In this study, a computational fluid-structure interaction (FSI) framework for characteristic deformations in insect's wings is proposed. The proposed framework consists of a pixel wing model using a structured shell finite element mesh, a projection method for the monolithic FSI monolithic equations using an algebraic splitting, and the FSI dynamic similarity law to measure dynamic similarity between model's and actual insect's flights. It is shown that the proposed framework can directly simulate passive feathering and cambering in insect's wings caused by the FSI, whose magnitudes are very close to those of actual insects.

DOI： 10.23967/coupled.2021.012

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85206908368&origin=inward

圧電エネルギーハーベスティングにおける構造‐圧電‐回路連成現象の分離反復型解析

石原大輔, 高田黎, プラカシャチガハリラメゴウダ, 高山直人

日本機械学会計算力学部門 CMD2020計力スクウェア研究報告集 A-TS 01-27 Report No. 2-12, 5pages 2020年12月

昆虫羽ばたき翼に生じる特徴的弾性変形の流体構造連成解析

大西南斗, 大戸悠司, 石破和弥, 石原大輔

日本機械学会計算力学部門 CMD2020計力スクウェア研究報告集 A-TS 01-27 Report No. 2-13, 5pages 2020年12月

Polymer Micromachined Transmission for Insect-Inspired Flapping Wing Nano Air Vehicles* 査読有り

Ishihara D., Murakami S., Ohira N., Ueo J., Takagi M., Urakawa K., Horie T.

15th IEEE International Conference on Nano/Micro Engineered and Molecular System, NEMS 2020 176 - 179 2020年09月

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

© 2020 IEEE. This paper presents a polymer micromachined transmission from small translational displacement to large rotational displacement, which has the potential for further miniaturizing a variety of micro robot applications such as insect-inspired flapping wing nano air vehicles (FWNAVs). Innovative claims include (1) the transmission mechanism using a geometrically nonlinear bending, (2) the microfabrication process consisting of only the standard steps such as the deposition, the photolithography, the curing, and the release without any post-assembling, and (3) the stroke angle of about 40° without any dynamic effect.

DOI： 10.1109/NEMS50311.2020.9265594

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85098514474&origin=inward

Finite element analysis of a thin piezoelectric bimorph with a metal shim using solid direct-piezoelectric and shell inverse-piezoelectric coupling with pseudo direct-piezoelectric evaluation 査読有り

Ramegowda P.C., Ishihara D., Takata R., Niho T., Horie T.

Composite Structures 245 2020年08月

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）

© 2020 Elsevier Ltd A thin triple-layer piezoelectric bender, also known as a piezoelectric bimorph with a metal shim, consists of an elastic layer (metal shim) sandwiched between two piezoelectric layers. It is one of the most commonly used piezoelectric composite structures in both sensing and actuation applications. Therefore, this study deals with the coupled piezoelectric-structure interaction analysis of a thin piezoelectric bimorph with a metal shim. In this work, the best features of the solid and shell elements were combined to analyze the piezoelectric and structural fields, respectively, in a thin piezoelectric bimorph with a metal shim. This approach addresses the shortcomings of using a single finite element mesh for both the piezoelectric and structural fields. A transformation method using the block Gauss-Seidel algorithm is employed to exchange the variables between solid direct-piezoelectric and shell inverse-piezoelectric analyses. The metal layer can be analyzed as an elastic body with electrical boundary conditions. A pseudo direct-piezoelectric evaluation method for the metal shim in the piezoelectric analysis is proposed. This method allows us to reuse the existing piezoelectric analysis program, where the metal shim is analyzed as the pseudo direct-piezoelectric material in a single analysis procedure. The homogenization method for the evaluation of bending rigidity and mass is used for modeling the single shell structure in the inverse-piezoelectric analysis of a thin piezoelectric bimorph with a metal layer. Numerical results are given for various electrical configurations of actuators and sensors to validate the present method. Comparison with an exact solution illustrates the accuracy, efficiency, and capability of the developed solid direct and shell inverse-piezoelectric analysis coupled with a pseudo direct-piezoelectric evaluation method to capture the sensor and actuator response of a thin piezoelectric bimorph with a metal shim.

DOI： 10.1016/j.compstruct.2020.112284

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85082720615&origin=inward

Hierarchically decomposed finite element method for a triply coupled piezoelectric, structure, and fluid fields of a thin piezoelectric bimorph in fluid 査読有り

Ramegowda P.C., Ishihara D., Takata R., Niho T., Horie T.

Computer Methods in Applied Mechanics and Engineering 365 2020年06月

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）

© 2020 Elsevier B.V. This paper proposes a numerical method for analyzing a thin piezoelectric bimorph in fluid. A hierarchically decomposed finite element method (FEM) is proposed for modeling the triply coupled piezoelectric-structure–fluid interaction. The electromechanical coupling (piezoelectric-structure interaction) behavior in a thin piezoelectric bimorph is described by the classical constitutive equation, the incompressible fluid flows by the Navier–Stokes equation and the structure by the Cauchy equation of motion. The piezoelectric-structure–fluid interaction system is decomposed into subsystems of fluid–structure interaction (FSI) and piezoelectric field, then the piezoelectric field and the FSI are coupled using the block Gauss–Seidel method, the fluid–structure interaction is split into the fluid–structure velocity field and the pressure field using an algebraic splitting and the fluid–structure velocity field is partitioned into fluid velocity field and structure velocity field. Using the proposed method, the resonance characteristics of a piezoelectric bimorph cantilever made of PVDF and PZT-5H material in fluid are investigated for actuation and sensor configurations.

DOI： 10.1016/j.cma.2020.113006

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85082661887&origin=inward

炭素繊維複合材およびドライクロスの誘導加熱解析

中村俊太，堀江知義，二保知也，石原大輔

第32回「電磁力関連のダイナミクス」シンポジウム講演論文集 65 - 70 2020年05月

電気結合係数の大きな圧電材料によるバイモルフ型アクチュエータに対する解析方法の比較検討

石原大輔，熊谷武尊，相川昇壱，プラカシャチガハリラメゴウダ，二保知也，堀江知義

第32回「電磁力関連のダイナミクス」シンポジウム講演論文集 75 - 76 2020年05月

Element-quality-based stiffening for the pseudoelastic mesh-moving technique 査読有り

Ishihara D., Goto A., Onishi M., Horie T., Niho T.

International Journal of Computational Methods 17 ( 4 ) 2020年05月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2020 World Scientific Publishing Company. In this study, element-quality-based stiffening (EQBS) was developed as a method of maintaining mesh quality in the pseudoelastic mesh-moving technique. The proposed EQBS technique increases the stiffness of the element based on two element quality parameters, the element area and shape; this differs from techniques used in previous studies. Importantly, EQBS includes the previously proposed Jacobian-based stiffening (JBS) and minimum height-based stiffening (MHBS) techniques as a specific case. Therefore, it is quite general scenario of the selective stiffening of the mesh. The proposed EQBS technique was applied to the mesh-moving of a rectangular domain including a structure consisting of a square and a fin that undergo large translations and rotations. The proposed EQBS technique showed better performance than JBS on test problems with large translations and rotations applied to the structure. This is because EQBS considers the shear deformation of the element in addition to the tensile and compressive deformations.

DOI： 10.1142/S0219876218501463

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85055150115&origin=inward

Fluid-structure and electric interaction analysis of piezoelectric flap in a channel using a strongly coupled FEM scheme 査読有り

Ramegowda P.C., Ishihara D., Takata R., Niho T., Horie T.

Proceedings of the 6th European Conference on Computational Mechanics: Solids, Structures and Coupled Problems, ECCM 2018 and 7th European Conference on Computational Fluid Dynamics, ECFD 2018 382 - 393 2020年01月

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）

Copyright © Crown copyright (2018).All right reserved. Electric and Fluid-Structure interaction (EFSI) is a complex coupled multi-physics phenomenon appears in microelectromechanical system (MEMS) when these microdevices are operated in a fluid media. In this study, the EFSI phenomena refer to a combination of electromechanical (electric-structure interaction) coupling and fluid-structure interaction coupling. Both the electromechanical coupling and the fluid-structure interaction can be simulated in a monolithic way or in a partitioned iteration way. In the proposed method the electromechanical coupling is simulated in a partitioned iterative way with separate solvers for the electrical and mechanical equations using block Gauss-Seidel (BGS) iteration method, while the fluid-structure interaction is simulated in a monolithic way by solving the fluid and structure equations simultaneously using a projection method. The proposed algorithm combines these two methods to analyze the strongly coupled EFSI in MEMS. The proposed method is applied to a flexible flap made of piezoelectric bimorph actuator in a converging channel. The EFSI analysis results show a good agreement with FSI results when a very low input bias voltage is applied to the actuator.

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85065786873&origin=inward

逆圧電‐圧電‐電気回路連成現象の分離反復型解法査読有り

石原大輔, 高田黎, Prakasha Chigahalli Ramegowda

日本計算工学会論文集 ( 一般社団法人日本計算工学会 ) 2020 ( 0 ) 20200015 - 20200015 2020年01月

担当区分：筆頭著者記述言語：日本語掲載種別：研究論文（学術雑誌）

アクチュエータやセンサに用いられる圧電バイモルフは，通常，電気回路に接続される．この場合，圧電バイモルフの機械的挙動は回路からの電荷の影響を受け，また圧電バイモルフは回路内でコンデンサのように振る舞う．ゆえに，圧電バイモルフを用いる電気機械システムの設計プロセスにおいて，逆圧電‐圧電連成に加えて，圧電バイモルフと回路との連成を考慮する必要がある．本研究では，この逆圧電‐圧電‐回路連成問題に対する新しい有限要素解析手法を提案する．薄い複合材圧電バイモルフを考慮するために，逆圧電解析にはシェル要素，圧電解析にはソリッド要素を用いる．従って，ソリッドとシェルの間における変数変換方法を用いる．回路解析は1自由度で記述する．また，圧電‐回路連成において，電位と電荷の連続性に基づく連成条件式を提案する．連成アルゴリズムは，ブロックガウスザイデル法に基づいている．逆圧電解析において，曲げ剛性および質量に対する材料の複合則を用い，圧電解析において，導体の疑似圧電体評価法を用いる．最後に，本解法によって，RC回路およびシャントダンピングにおける連成現象を正確に解析できることを示す．

DOI： 10.11421/jsces.2020.20200015

その他リンク： https://ci.nii.ac.jp/naid/130007885624

Modeling the cambering of the flapping wings of an insect using rectangular shell finite elements 査読有り

Onishi Minato, Ishihara Daisuke

日本シミュレーション学会英文誌 ( 一般社団法人日本シミュレーション学会 ) 7 ( 1 ) 181 - 188 2020年01月

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）

Cambering in the flapping wings of insects plays an important role in the aerodynamic performance of their flight. In a previous study, the authors proposed a wing model using shell finite elements to elucidate the mechanism of cambering. However, the analysis of a strongly coupled fluid–structure system using this model would be quite computationally expensive because of the necessity of robust mesh-moving techniques. Therefore, in this study, a new wing model using rectangular shell finite elements is proposed. In the proposed model, the veins and membranes are described as pseudo-elastic materials. The cambering of the proposed model is investigated by comparison with the previous model.

DOI： 10.15748/jasse.7.181