研究者詳細 - 玉川　雅章

論文 - 玉川　雅章

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Computational study on aerodynamic characteristics and behaviour of s5010 airfoil 査読有り国際誌

Yazik M.H.M., Tamagawa M., Sultan M.T.H., Adzrif A.

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 66 ( 1 ) 42 - 52 2020年02月

記述言語：英語掲載種別：研究論文（学術雑誌）

In this study, a numerical simulation has been conducted to understand the effect of angle of attack on the S5010 airfoil profile. ANSYS Fluent was utilized with the compliment of experimental data from literature. The 2-D computational fluid dynamic simulation were conducted to find the lift, drag and lift-to-drag ratio of S5010 airfoil at various angle of attack up till the stalling point. The k-ω SST turbulent model was used to model the turbulent flow during the simulation. The data obtained was compared with available experimental data for validity and later extended to obtain stall angle of the airfoil. It was found that the stall angle of S5010 airfoil was at 11 and the maximum lift-to-drag ratio was obtained at 7.8. Considering the simulation, acceptable solution has been achieved that can be used to compare with other airfoil profile in the future.

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Computational Study on Aerodynamic Characteristics and Behaviour of S5010 Airfoil 査読有り国際誌

Muhamad Hasfanizam Mat Yazik , Masaaki Tamagawa , Mohamed Thariq Hameed Sultan , Adi Adzrif

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences ( PENERBIT AKADEMIA BARU ) 66 ( 1 ) 42 - 52 2020年02月

Fluid Structure Interaction on Paravalvular Leakage of Transcatheter Aortic Valve Implantation Related to Aortic Stenosis: A Patient-Specific Case 査読有り国際誌

Basri A.A., Zuber M., Basri E.I., Zakaria M.S., Aziz A.F.A., Tamagawa M., Ahmad K.A.

Computational and Mathematical Methods in Medicine 2020 2020年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

This study investigated the impact of paravalvular leakage (PVL) in relation to the different valve openings of the transcatheter aortic valve implantation (TAVI) valve using the fluid structure interaction (FSI) approach. Limited studies were found on the subject of FSI with regards to TAVI-PVL condition, which involves both fluid and structural responses in coupling interaction. Hence, further FSI simulation with the two-way coupling method is implemented to investigate the effects of hemodynamics blood flow along the patient-specific aorta model subjected to the interrelationship between PVL and the different valve openings using the established FSI software ANSYS 16.1. A 3D patient-specific aorta model is constructed using MIMICS software. The TAVI valve identical to Edward SAPIEN XT 26 (Edwards Lifesciences, Irvine, California), at different Geometrical Orifice Areas (GOAs), is implanted into the patient's aortic annulus. The leaflet opening of the TAVI valve is drawn according to severity of GOA opening represented in terms of 100%, 80%, 60%, and 40% opening, respectively. The result proved that the smallest percentage of GOA opening produced the highest possibility of PVL, increased the recirculatory flow proximally to the inner wall of the ascending aorta, and produced lower backflow velocity streamlines through the side area of PVL region. Overall, 40% GOA produced 89.17% increment of maximum velocity magnitude, 19.97% of pressure drop, 65.70% of maximum WSS magnitude, and a decrement of 33.62% total displacement magnitude with respect to the 100% GOA.

DOI： 10.1155/2020/9163085

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Significant attributes identification for indoor cycling fatigue classification 査読有り国際誌

Tang S., Loh W., Tamagawa M.

AIP Conference Proceedings 2138 2019年08月

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 Author(s). Indoor cycling was commonly examined from the riding posture, saddle height or pedal force to analyze the muscular activity on cyclists' lower limbs. While strong muscular strength and proper riding posture are important to minimize strain, the significances of these attributes on cycling fatigue were unclear. An attempt was made to identify significant attributing features for indoor cycling fatigue classification based on an experimental study involving twenty healthy postgraduates. The participants were tasked to perform an indoor cycling fatigue experiment at 6km/h with gradual speed increment till fatigue level achieved. The accelerometry, sacral trajectory and the lower limb kinematic changes were measured. Significant feature subset selection was determined using the wrapper approach with IBk algorithm. The featured data were later classified on IBk, SMO, ZeroR, J48 and Vote followed by subsequent discriminant analysis. The results demonstrated that the significant attributes yielded 95.0% and 75% classification accuracies (training data) but yielded 72.5% and 65.0% (10 folds cross-validation) on Vote and the discriminant analysis respectively. Findings revealed that the cycle frequency is the most significant attribute exerting a major effect on cycling fatigue while StepRegML and Disp_ML attributes contribute little to distinguish fatigue and pre-fatigue cycling motion.

DOI： 10.1063/1.5121137

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Effects of impinging jet flow on platelets adhesion by computational fluid dynamics (CFD) analysis with consideration of particle motion for predicting thrombus formation 査読有り国際誌

Nakata S., Miyamura Y., Tamagawa M.

ICIC Express Letters, Part B: Applications ( ICIC International 学会 ) 10 ( 8 ) 755 - 762 2019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）

© 2019, ICIC International. All rights reserved. To establish the prediction method of thrombus formation on the wall by computational fluid dynamics (CFD), it is very important to find out the effects of flow field on platelet adhesion on the wall. In this paper, the particle motions on impinging jet flow which has the stagnation point were analyzed, and the adhered particles on the wall were also analyzed. Especially, discrete particles by using the impinging jet flow that Affeld used for the platelet adhesion experiment were analyzed, and the adhesion mecha- nism of particles simulating platelets was investigated by CFD. This adhesion mechanism is corresponded to starting point for thrombus formation on shear flow. After analyzing three-dimensional flow field particle motions by using fundamental equations on the im- pinging jet flow, the platelet motions can be obtained. From the result of CFD comparing with experiment, it was concluded that the platelet motion was able to be simulated on the impinging jet flow by using particle tracking method with consideration of density dif- ference. It was also concluded that predicted adhered distribution did not agree well with experimental result even though the tendency of distribution of adhered platelet could be obtained. Further investigation and trials for this validation will be needed to establish the prediction method.

DOI： 10.24507/icicelb.10.08.755

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Generation of micro-scale shock waves by focussing short-time pulse laser and measurement of pressure for development of regenerative cell-culture systems 査読有り国際誌

Masaaki TAMAGAWA, Ruosuke TERAJIMA, Ryo SAKAI

Proc. of the 32nd International Shock Wave Symposium OR-08-1393.1 - OR-08-0393.4 OR-08-0393 (4 pages) 2019年07月

Evaluation of Thrombus Formation around a Peripheral Intravenous Catheter for Infants 査読有り

Taishin Yamaguchi, Yuko Miyamura and Masaaki Tamagawa

Proc. of 6th International Conference on Computational & Mathematical Biomedical Engineering (CMBE2019) 2 805 - 808 2019年06月

A Cartesian non-boundary fitted grid method on complex geometries and its application to the blood flow in the aorta using OpenFOAM 査読有り国際誌

Zakaria M., Ismail F., Tamagawa M., Aziz A., Wiriadidjaja S., Basri A., Ahmad K.

Mathematics and Computers in Simulation 159 220 - 250 2019年05月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2018 International Association for Mathematics and Computers in Simulation (IMACS) The aim of this paper is to develop a new non-boundary fitted (NBF) Cartesian grid method to compute flows in a complex geometry such as that found in a human aorta. The algorithm is based on the volume of fluid (VOF) colour function in a regular Cartesian grid through the open source OpenFOAM platform. The solid was treated as a fluid with very high viscosity to theoretically reduce its deformability, and subsequently satisfy a no-slip condition at the boundary. We also introduced the artificial term of the colour function into an algebraic system of momentum equations, which had a significant impact on the non deformability of solid domain and originality of this study. The developed solver, NBF-VOF, is then thoroughly validated using a variety of numerical and experimental results available in the literature Finally, we demonstrated the applicability of our code on flows in a complex geometry based on patient-specific image data robustly without the need for complex meshing generation procedures that conventional boundary fitted (BF) methods do.

DOI： 10.1016/j.matcom.2018.11.014

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FINITE ELEMENT ANALYSIS of URINARY BLADDER WALL THICKNESS at DIFFERENT PRESSURE CONDITION 査読有り国際誌

Keni L., Kalburgi S., Hameed B., Zuber M., Tamagawa M., Shenoy B.

Journal of Mechanics in Medicine and Biology 19 ( 5 ) 2019年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 World Scientific Publishing Company. In this work, a 3D urinary bladder was subjected to various pressure loading conditions mimicking the bladder filling volume. The bladder layer consisting of adventitia, detrusor and mucosa layer having different mechanical properties produced different deformation and stresses when subjected to the varying loads. The volume of the bladder changed to 231.34ml which was 128.91% higher than the assumed initial volume of 50ml on application of 18kPa of pressure. The detrusor layer which is thickest of the bladder wall reduced to 1.312mm from 4.4mm, recording a 108% change in its thickness at 18kPa pressure. The maximum von-Mises stress obtained were significantly higher in case of the Mucosa layer when compared to the detrusor and adventia layer. The unique layup of the bladder wall having different properties plays a major role in sustaining adverse pressure gradients and absorbing high stresses.

DOI： 10.1142/S0219519419500295

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Simulation of platelet aggregation on the wall of orifice flow by dissipative particle dynamics accelerated by openmp 査読有り

Yi Y., Tamagawa M.

ICIC Express Letters, Part B: Applications 9 ( 7 ) 665 - 672 2018年07月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2018, ICIC International. All rights reserved. Platelet transport and aggregation are two important steps in the formation of white thrombus. Platelet transport has been investigated by finite difference method (FDM) in our previous research. However, FDM cannot simulate platelet aggregation. Other numerical methods, such as dissipative particle dynamics (DPD), should be used to simulate platelet aggregation. And DPD can be combined with FDM to have a complete analysis of the formation of white thrombus. However, vast computational time in DPD system is needed if particle number is big. To decrease this vast computational time and have a balance with FDM, parallel computation is an effective method. This paper describes the parallelization of DPD by OpenMP. For parallelization performance, it is found that the computational time is efficiently shortened by OpenMP. After the confirmation of the high performance by OpenMP, platelet aggregations with different initial platelet numbers are simulated in orifice flow. It is concluded that recirculation area and reattachment point have higher probability of platelet aggregation.

DOI： 10.24507/icicelb.09.07.665

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Effects of flow asymmetricity on thrombus formation and hemolysis properties in the pipe orifice flow by CFD analysis 査読有り国際誌

Hirayama C., Miyamura Y., Tamagawa M.

ICIC Express Letters, Part B: Applications 9 ( 7 ) 673 - 680 2018年07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）

© 2018, ICIC International. All rights reserved. In this paper, to discuss asymmetricity of the thrombus formation on the wall surface, flow analysis on the three-dimensional flow in the pipe orifice was carried out, and the effects of asymmetricity of wall shear stress and shear stress on thrombus formation and hemolysis properties were investigated. As for thrombus formation, the asymmetricity of wall shear stress was obtained and compared with that of visualization of thrombus formation. As for hemolysis properties on orifice flows, it was evaluated by Lagrangian fatigue accumulation method in case of axisymmetric flow and three-dimensional flow. From the results, it was suggested that there is the possibility for wall shear stress and other transport process of concentration to influence circumferential thrombus formation. In addition to this, by comparing the hemolysis evaluation of the axisymmetric flow with the three-dimensional flow, it was also suggested that the flow asymmetricity has effects on hemolysis properties by comparing with axisymmetric flow.

DOI： 10.24507/icicelb.09.07.673

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Computational fluid dynamics study of blood flow in aorta using OpenFOAM 査読有り国際誌

Zakaria M.S., Ismail F., Tamagawa M., Abdul Azi A.F., Wiriadidjaya S., Basri A.A., Ahmad K.A.

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 43 ( 1 ) 81 - 89 2018年03月

記述言語：英語掲載種別：研究論文（学術雑誌）

Understanding of flow pattern behaviour inside the aorta contributes significantly in diseases treatment artificial design. Objective of present study is to simulate the blood flow in patient specific aorta using open source computational fluid dynamics (CFD) platform OpenFOAM. The real geometry was obtained from real male Malaysian patient. There are not much data available in literature incorporate real geometry of aorta due to complex geometry. The validation is done against existing experimental result of the 90 degree curve tube model. It was shown that our method is able to capture complex flow in the curve tube like secondary and separation flow that responsible for development of wall shear stress at the tube wall. These flow physics could have similarity in aorta blood flow. Finally, we apply our method with anatomy human aorta with pulsatile inlet condition. Further comparison is made with unstructured boundary fitted mesh. The final result shows that the detailed flow physics can be captured in an aorta.

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Development of Novel Hybrid Method using Finite Differnce Method and Dissipative Particle Dynamics for Prediction of Thrombus Formation 査読有り国際誌

Yingming YI, Masaaki TAMAGAWA

Proc. of 4th International Conference on Computational Method in Engineering and Health Science (ICCMEH2015) HS025.1 - HS025.6 HS025 8pages 2017年12月

衝突試験用人体模型を用いた転倒による頭蓋骨変形の計算

中野正博, 松浦弘幸, 玉川雅章, 行正徹, 石川耕介, 山中真

バイオメディカル・ファジィ・システム学会大会講演論文集 ( バイオメディカル・ファジィ・システム学会 ) 30 ( 0 ) 225 - 228 2017年11月

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 order to investigate various dangers of fall down, we have conducted the experiment using human dummy model in Japan Automobile Research Institute (JARI). We have measured accelerations inside of the head in time step of 1/10000 sec with the accuracy within 1%. From the acceleration, we calculate the time development of velocity and position of the center of the head. HIC and the deformation are calculated. for two backward falls from standing position. As a conclusion, we found the deformation of the skull is similar, about 2.4mm for two falls down, although their HIC are different from each other .

DOI： 10.24466/pacbfsa.30.0_225

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CiNii Research

その他リンク： https://search.jamas.or.jp/link/ui/2019100617

乳幼児啼泣時の点滴留置針まわりの血栓形成とそのモデルのCFD による流動解析

宮村裕子, Shet Pramod, 吉牟田純一郎, Pai Raghuvir, 玉川雅章

バイオメディカル・ファジィ・システム学会大会講演論文集 ( バイオメディカル・ファジィ・システム学会 ) 30 ( 0 ) 161 - 164 2017年11月

担当区分：責任著者記述言語：日本語掲載種別：研究論文（研究会，シンポジウム資料等）

This paper describes the relation between infantile crying and thrombus generation near intravenous indwelling needle in veins. In this study, it is assumed that the difference of pressure or flow rate between normal and infantile crying causes thrombus formation. First of all, the blood pressure of infant are measured, and the difference of blood pressure between normal status and infantile crying. It was found that the blood pressure increases according to the infantile crying, and the difference of blood is approximately 20 mmHg. To investigate the flow field of the flow, CFD analysis around the indwelling needle of drip injection (catheter) in the infantile vein was done. The results show that the increasing flow rate or velocity make the accumulation of particle around the inlet of the catheter.

DOI： 10.24466/pacbfsa.30.0_161

CiNii Article

CiNii Research

その他リンク： https://search.jamas.or.jp/link/ui/2019100608

後方転倒時における衝撃緩和用防具の評価

石川耕介, 松浦弘幸, 中野正博, 玉川雅章, 行正徹, 巨東英

バイオメディカル・ファジィ・システム学会大会講演論文集 ( バイオメディカル・ファジィ・システム学会 ) 30 ( 0 ) 177 - 178 2017年11月

担当区分：責任著者記述言語：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 shock mitigation armor at the time of falling backwards, and as a result we found that armor protecting head and neck is the best result. Moreover, even if the shock was relieved, it was found that the armor where the head touches the ground is not suitable for a rearward fall

DOI： 10.24466/pacbfsa.30.0_177

CiNii Article

CiNii Research

その他リンク： https://search.jamas.or.jp/link/ui/2019100611

Review of numerical methods for simulation of mechanical heart valves and the potential for blood clotting 査読有り

Mohamad S. Zakaria, Farzad Ismail, Masaaki Tamagawa, Ahmad F. A Aziz, Surjatin Wiriadidjaya, Adi A. Basri, Kamarul A. Ahmad

Medical & Biological Engineering & Computing 55 ( 9 ) 1519 - 1548 In press 2017年09月

Review of numerical methods for simulation of mechanical heart valves and the potential for blood clotting 査読有り国際誌

Zakaria M., Ismail F., Tamagawa M., Aziz A., Wiriadidjaja S., Basri A., Ahmad K.

Medical and Biological Engineering and Computing 55 ( 9 ) 1519 - 1548 2017年09月

記述言語：英語掲載種別：研究論文（学術雑誌）

Even though the mechanical heart valve (MHV) has been used routinely in clinical practice for over 60 years, the occurrence of serious complications such as blood clotting remains to be elucidated. This paper reviews the progress that has been made over the years in terms of numerical simulation method and the contribution of abnormal flow toward blood clotting from MHVs in the aortic position. It is believed that this review would likely be of interest to some readers in various disciplines, such as engineers, scientists, mathematicians and surgeons, to understand the phenomenon of blood clotting in MHVs through computational fluid dynamics.

DOI： 10.1007/s11517-017-1688-9

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Prediction of Thrombus Formation on the Wall by High Shear Rate on Couette and Orifice Blood Flows 査読有り国際誌

Yingming YI, Masaaki TAMAGAWA and Weiwei SHI

Journal of Medical Imaging and Health Informatics 7 ( 1 ) 79 - 84 2017年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

In order to predict thrombus formation on high shear flows, previous thrombus model based on concentration transport was used. However, the model didn't consider the effect of shear on thrombosis. In this paper, a new model which considers the effect of shear is proposed. Platelet activation is an important process during thrombosis. In this model, reaction rate of platelet activation is redefined to be the product of agonist concentration and shear rate factor instead of original only agonist activation model. Using this new model, platelet transport and deposition are computed on high shear flows such as Couette flow and orifice flows. In case of Couette flow, the results show that number rate of activated platelets increases linearly with shear rate when shear rate is beyond its threshold. In case of orifice flow, the results show that platelet activation process is similar for every orifice configurations, but deposition rate of activated platelet differs from each other. The deposition rate depends on the shear rate in these orifices.

DOI： 10.1166/jmihi.2017.1841

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Computational Fluid Dynamics study of airflow and microparticle deposition in a constricted pharyngeal representing Obstructive Sleep Apnea 査読有り

V.N. Riazuddin, M. Zubair, M. Tamagawa, N.H.A. Rashid, K. A. Ahmad

Journal of Medical Imaging and Health Informatics 6 ( 1 ) 1 - 6 2017年01月

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