Yokomori, Takeshi

写真a

Affiliation

Faculty of Science and Technology, Department of Mechanical Engineering (Yagami)

Position

Associate Professor

E-mail Address

E-mail address

Related Websites

External Links

Career 【 Display / hide

  • 2003.10
    -
    2004.04

    Researcher, Institute of Fluid Science, Tohoku University

  • 2004.04
    -
    2007.03

    JSPS Fellow(PD), Institute of Fluid Science, Tohoku University

  • 2005.04
    -
    2006.03

    Guest Researcher, Department of Mechanical and Aerospace Engineering, Princeton University, USA

  • 2007.04
    -
    2013.03

    Lecturer, Department of Mechanical Engineering, Faculty of Science and Technology, Keio University

  • 2011.04
    -
    2013.03

    慶應義塾大学 日吉2年生クラス担任

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Academic Background 【 Display / hide

  • 1998.03

    Keio University, Faculty of Science and Technology, Department of Mechanical Engineering

    University, Graduated

  • 2000.03

    Keio University, Graduate School of Science and Technology, School of Mechanical Engineering

    Graduate School, Completed, Master's course

  • 2003.09

    Keio University, Graduate School of Science and Technology, School of Science for Open and Environmental Systems

    Graduate School, Withdrawal after completion of doctoral course requirements, Doctoral course

Academic Degrees 【 Display / hide

  • Ph.D, Keio University, Coursework, 2004.03

 

Research Areas 【 Display / hide

  • Thermal engineering (Thermal Engineering)

Research Keywords 【 Display / hide

  • レーザー計測

  • Reactive thermal fluid

  • Flame

  • Combustion

  • Combustion synthesis

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Research Themes 【 Display / hide

  • Combustion synthesis of nano-phosphor, 

    2005
    -
    Present

  • 多孔質微粒子の燃焼合成法の開発, 

    2010
    -
    Present

  • コアシェル微粒子の燃焼合成法の開発, 

    2010
    -
    Present

  • Combustion synthesis of Carbon nanotubes, 

    2002
    -
    2009

  • Control of catalytic combustion, 

    2006
    -
    Present

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Papers 【 Display / hide

  • Characteristics of counterflow premixed flames with low frequency composition fluctuations

    Tomidokoro T., Yokomori T., Im H., Ueda T.

    Combustion and Flame (Elsevier)  212   13 - 24 2020.02

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  00102180

     View Summary

    © 2019 The Combustion Institute The response of laminar methane/air counterflow premixed flames under sinusoidal equivalence ratio oscillation was investigated numerically. The timescales of the oscillation were chosen to be sufficiently longer than the flame timescale so that the flame responds quasi-steadily. The response of periodically stratified flame (SF) with a detailed reaction mechanism exhibited the “back-support” effect, in that the consumption speed Sc response deviated increasingly from Sc of steady homogeneous flames (HFs) at higher oscillation frequencies. It was shown that even when the imposed oscillation timescale is much longer than the flame timescale, the flame response can still be delayed under a sufficiently large equivalence ratio gradient. Subsequently, the above results were compared with those obtained with a global four-step mechanism that omits back-diffusion radicals into the reaction zone. As a result, SFs with the global mechanism displayed a much smaller back-support effect in both lean and rich mixtures. Further analysis with modified diffusion coefficients revealed the dominant roles of H2 and radical species diffusion in inducing the back-support effect. Contrary to the previous findings, variations in burned gas temperature were found to play a negligible role in modifying Sc. Additionally, the hysteresis of the back-support effect under periodical stratification was found to be more prominent on the richer side because of the presence of a larger H2 pool.

  • Thermal efficiency improvement of super-lean burn SI engine by stratified water insulation on piston top surface

    Tsuyoshi Nagasawa, Yuichi Okura, Ryota Yamada, Susumu Sato, Hidenori Kosaka, Takeshi Yokomori, Norimasa Iida

    International Journal of Engine Research accepted 2020

    Research paper (scientific journal), Joint Work, Accepted

  • Development of cycle-to-cycle variation of the tumble flow motion in a cylinder of an SI IC engine with Miller cycle

    Masayoshi Matsuda, Takeshi Yokomori, Masayasu Shimura, Yuki Minamoto, Mamoru Tanahashi, Norimasa Iida

    International Journal of Engine Research accepted 2020

    Research paper (scientific journal), Joint Work, Accepted

  • Precision evaluation of phosphors for the lifetime method in phosphor thermometry

    Kazuki Tsuchiya, Kento Sako, Naohiro Ishiwada, and Takeshi Yokomori

    Measurement Science and Technology (Measurement Science and Technology)  accepted ( 6 )  2020

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  09570233

     View Summary

    © 2020 IOP Publishing Ltd. The precision of the lifetime method in phosphor thermometry was examined in terms of the uncertainty in temperature prediction. Such uncertainty can be estimated using the rate of change in lifetime with temperature (lifetime sensitivity) and the uncertainty in measured lifetime. This uncertainty depends on phosphorescence characteristics such as phosphorescence intensity and lifetime decay shape. In this study, we proposed a method of calculating uncertainties in measured lifetimes by the estimated regression coefficients in measured decay signals of phosphors. To demonstrate this evaluation, the uncertainties in the predicted temperatures of some common phosphors (MFG, GGG:Cr, Y2O3:Eu) were calculated. Consequently, the temperature predictions by the lifetime method with MFG, GGG:Cr, and Y2O3:Eu showed high precision at about 800 K, 700 K, and 900 K, respectively. This method of evaluating precision by using both lifetime sensitivity and uncertainty in lifetime helps to improve the appropriate use of phosphors for the lifetime method in phosphor thermometry.

  • Response in Bunsen flame with variation in a natural gas composition and control for stabilizing the flame variation

    UMEZAWA Shuichi, ISHIBASHI Takuya, OKAMOTO Michikazu, YOKOMORI Takeshi, UEDA Toshihisa

    Transactions of the JSME (in Japanese) (The Japan Society of Mechanical Engineers)  86 ( 884 ) 19 - 00432-19-00432 2020

    Joint Work, Except for reviews

     View Summary

    <p>This study investigated experimentally a response of premixed Bunsen flame to transient change in a fuel composition and a method to control the variation. Fuel mixtures were composed of methane, ethane and propane. The volumetric fraction of methane was varied from 92 % to 76 % by 4 % and the ethane/propane ratio was 5. Transition time of the fuel composition was 1, 5, 10 and 20 s. Flow velocity and the equivalence ratio were 0.8 m/s and 0.85 respectively before the transition. Channel length <i>L</i> between the merging point of fuels and the point of air was 0, 500, 1000, 1500 mm. The motion of flame was recorded by a high-speed video camera at 60 fps. The experiment was conducted under the fuel flow rate constant and the equivalence ratio constant conditions. In the former condition, the flame height varied almost linearly not depending on the conditions. In the latter condition, variation of the steady flame height was smaller than the former condition. However, the unsteady flame height exceeded or fell below temporarily the steady flame height. This is due to the time lag between the transmission of fuel flow rate variation and fuel compositions variation. Therefore, considering this time lag, the experiment was conducted with a system which had a density meter to detect the fuel composition variation. The system controlled automatically the fuel flow rate. At long <i>L</i> and short transition time, there were some peaks in the flame height variation. It is considered that this is caused by the difference between the actual density and the output of the density meter due to Taylor dispersion and response time of the density meter. However, the flame height variation was smaller than the variation without control, and particularly at long transition time, the variation was suppressed sufficiently.</p>

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Papers, etc., Registered in KOARA 【 Display / hide

Reviews, Commentaries, etc. 【 Display / hide

  • Non-contact temperature measurement by two-color phosphor thermometry

    Takeshi YOKOMORI, Naohiro ISHIWADA

    Heat Transfer (日本伝熱学会)  58 ( 245 ) 15 - 20 2019.10

    Introduction and explanation (scientific journal), Joint Work

  • A high speed PIV measurement on the in-cylinder flow in an SI IC engine

    Masayoshi Matsuda, Takeshi Yokomori

    Image Laboratory 30 ( 9 ) 45 - 51 2019.09

    Introduction and explanation (commerce magazine), Joint Work

  • Research and Development on Super Lean Burn Combustion for High Efficiency SI Engines

    飯田訓正, 横森剛, 津江光洋, 北川敏明, 小酒英範, 三好明, 森吉泰生

    日本燃焼学会誌 (日本燃焼学会)  61 ( 197 ) 178 - 192 2019

    Introduction and explanation (scientific journal)

  • PIVを用いたエンジン筒内の流動計測技術

    横森剛, 松田昌祥

    計測と制御 57 ( 5 ) 313 - 317 2018.05

    Introduction and explanation (scientific journal)

Presentations 【 Display / hide

  • Effect of Surfactant on the Methane Hydrate Combustion

    K. Mizuochi, T. Yokomori, R. Ohmura, T. Ueda

    37th International Symposium on Combustion (Dublin, Ireland) , 2018.07, Poster (general), The Combustion Institute

     View Summary

    4P229

  • Criterion of the Transition from Quasi-Steady State to Non-Steady State Motion of Laminar Stagnating Premixed Flames with Fuel Concentration Oscillation

    T. Ueda, D. Kawasaki, K. Kashiwagi, T. Yokomori

    37th International Symposium on Combustion (Dublin, Ireland) , 2018.07, Poster (general), The Combustion Institute

     View Summary

    1P090

  • Numerical Simulation of Soot Particle Growth Including Sintering

    T. Kim, K. Takigawa, T. Yokomori

    37th International Symposium on Combustion (Dublin, Ireland) , 2018.07, Poster (general), The Combustion Institute

     View Summary

    2P045

  • Numerical Simulation of the Structure Growth of Silica Nanoparticles with a Conditional Quadrature Method of Moments Considering Fractal Dimension

    K. Takigawa, T. Yokomori

    37th International Symposium on Combustion (Dublin, Ireland) , 2018.07, Poster (general), The Combustion Institute

     View Summary

    2P049

  • Effect of Simultaneous Velocity and Equivalence Ratio Oscillations on the Laminar Premixed Stagnating Flame

    Y. Niwa, T. Tomidokoro, T. Yokomori, T. Ueda

    37th International Symposium on Combustion (Dublin, Ireland) , 2018.07, Poster (general), The Combustion Institute

     View Summary

    2P072

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • Elucidation of mechanism of combustion noise generation and modulation from turbulent lean premixed swirling flame

    2019.04
    -
    2022.03

    Kyoto University, 黒瀬 良一, 立花 繁, 横森 剛, Grant-in-Aid for Scientific Research (B)

     View Summary

    航空機用や産業用に用いられるガスタービンエンジンから発生する騒音は,ファンや排気ジェットを音源とする流体騒音と燃料/酸化剤の発熱反応を音源とする燃焼騒音とに大別される.近年,流体騒音の低減が着実に進んでいる一方で,燃焼騒音の寄与率が急激に上昇し,その低減が喫緊の課題とされている.しかし,燃焼騒音については,その発生メカニズムすら十分に理解されていない.また,燃焼騒音は壁反射や乱流渦等の外的因子により変調するが,その影響についてはこれまで議論されていない.本研究では,水素の乱流希薄予混合旋回火炎を対象に実験と数値解析を併用することより,燃焼騒音の発生・変調メカニズムを明らかにすることを目指す.

  • 平成27年度火炎伝播方向が高分子材料内部の温度分布に与える影響評価

    2015.09
    -
    2016.03

    国立研究開発法人宇宙航空研究開発機構(JAXA), 横森剛, Commissioned research, Principal Investigator

  • 高効率ガソリンエンジンのためのスーパーリーンバーン研究開発

    2014.10
    -
    2019.03

    独立行政法人 科学技術振興機構, 戦略的イノベーション創造プログラム(SIP)「革新的燃焼技術」, 飯田訓正, Research grant, Co-investigator

  • 平成26年度「火災安全性向上に向けた固体材料の燃焼現象に対する重力影響の評価」に関わる宇宙実験のデータ解析等(特に固体内部温度の計測)

    2014.08
    -
    2015.03

    国立大学法人豊橋技術科学大学, 横森剛, Joint research, Principal Investigator

  • 噴霧燃焼法を利用したコアシェル酸化物微粒子の新規合成手法の構築

    2014.04
    -
    2017.03

    Grant-in-Aid for Scientific Research, 横森剛, Research grant, Principal Investigator

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Intellectual Property Rights, etc. 【 Display / hide

  • 点火プラグ

    Application No.: 2018-023533  2017.12 

    Patent, Joint, National application

  • 燃焼制御方法

    Application No.: 特願2016-163095  2016.08 

    Announcement No.: 特開2018-31500  2018.03 

    Patent, Joint

  • 燃焼制御方法

    Application No.: 特願2016-162824  2016.08 

    Announcement No.: 特開2018-31499  2018.03 

    Patent, Joint

  • 温度及び酸素濃度測定装置

    Application No.: 特願2014-019213  2014.02 

    Announcement No.: 特開2015-145852  2015.08 

    Registration No.: 特許6264912号  2018.01

    Patent, Joint, National application

  • 加熱調理器の制御装置

    Application No.: 特願2011-209681  2011.09 

    Announcement No.: 特開2013-72562  2013.04 

    Patent, Joint, National application

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Awards 【 Display / hide

  • 日本機械学会熱工学部門一般表彰 貢献表彰

    2016.10, 日本機械学会

    Type of Award: Awards of National Conference, Council and Symposium.  Country: 日本

  • 日本機械学会関東支部関東学生会第55回学生員卒業研究発表会優秀講演賞

    松田昌祥, 藤澤直己, 横森 剛, 2016.03, 日本機械学会, 高速PIV 計測および数値計算を用いたガソリンエンジンにおける筒内流動解析

    Type of Award: Awards of National Conference, Council and Symposium

  • 日本機械学会若手優秀講演フェロー賞

    篠直希, 2015.11, 日本機械学会, 蛍光粒子を利用したガス流二次元温度・速度同時測定法の開発

    Type of Award: Awards of National Conference, Council and Symposium.  Country: 日本

  • 日本機械学会関東支部関東学生会第54回学生員卒業研究発表会優秀講演賞

    小川裕太, 楠拓朗, 横森剛, 2015.03, 日本機械学会, 二段火炎を導入したコアシェル粒子噴霧燃焼合成法の開発

    Type of Award: Awards of National Conference, Council and Symposium

  • 日本機械学会関東支部関東学生会第54回学生員卒業研究発表会優秀講演賞

    荻真太郎, 岡野紗耶, 横森剛, 2015.03, 日本機械学会, 燐光体の発光特性を利用した温度・酸素濃度同時測定手法の開発

    Type of Award: Awards of National Conference, Council and Symposium

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Courses Taught 【 Display / hide

  • THERMAL ENGINEERING

    2020

  • PROJECT LABORATORY IN MECHANICAL ENGINEERING

    2020

  • INDEPENDENT STUDY ON SCIENCE FOR OPEN AND ENVIRONMENTAL SYSTEMS

    2020

  • INDEPENDENT STUDIES IN MECHANICAL ENGINEERING

    2020

  • GRADUATE RESEARCH ON SCIENCE FOR OPEN AND ENVIRONMENTAL SYSTEMS 2

    2020

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Social Activities 【 Display / hide

  • 日本燃焼学会 平成25年度先進的燃焼技術の調査研究委員会 新概念燃焼技術 小委員会

    2013.12
    -
    2014.03
  • 日本伝熱学会

    2013.06
    -
    Present
  • 日本燃焼学会 震災後の社会・エネルギー情勢に必要とされる燃焼利用技術の調査研究分科会

    2013.04
    -
    Present
  • 日本機械学会 熱工学部門

    2013.04
    -
    Present
  • 日本機械学会 熱工学部門 総務委員会

    2013.04
    -
    Present

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Memberships in Academic Societies 【 Display / hide

  • Combustion Institute

     
  • 日本燃焼学会

     
  • 日本機械学会

     
  • American Institute of Aeronautics and Astronautics

     
  • 日本伝熱学会

     

Committee Experiences 【 Display / hide

  • 2015.04
    -
    2016.03

    Japanese Scientific Committee, The First Pacific Rim Thermal Engineering Conference

  • 2014.04
    -
    Present

    委員, 文部科学省 科学技術政策研究所科学技術動向研究センター

  • 2014.04
    -
    Present

    委員, 日本機械学会 熱工学部門 運営委員会

  • 2014.04
    -
    Present

    委員, 日本機械学会 熱工学部門 部門賞委員会

  • 2014.04
    -
    Present

    幹事, 日本機械学会 熱工学部門 総務委員会

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