Fujita Osamu

Institute for the Advancement of Graduate Education　Advancement of Educational Program DivisionSpecially Appointed Professor
Last Updated :2026/02/04

■Researcher basic information

Degree

  • Doctor of Engineering, Hokkaido University

Mail Address

  • ofujitaeng.hokudai.ac.jp

Researchmap personal page

Home Page URL

J-Global ID

Research Keyword

  • Combustion
  • Fire safety
  • Carbon neutrality
  • Microgravity
  • Space Utilization

Research Field

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering), Thermal engineering
  • Aerospace, marine, and maritime Engineering, Aerospace engineering

■Career

Career

  • Apr. 2022 - Present
    Institute for the Advancement of Graduate Education, Vice chair, Japan
  • Apr. 2003 - Mar. 2025
    Hokkaido University, Division of Mechanical and Aerospace Engineering, Professor, Professor, Japan
  • Apr. 1990 - Mar. 2003
    Hokkaido University, Department of Mechanical Engineering, Associate Professor
  • Mar. 1994 - Dec. 1994
    University of California at Berkeley, Department of Mechanical Engineering, Visiting Professor
  • Apr. 1987 - Mar. 1990
    Hokkaido University, Department of Mechanical Engineering, Assistant Professor
  • Apr. 1986 - Mar. 1987
    JSPS, Research fellowship for young scientist

Educational Background

  • Apr. 1984 - Mar. 1987, Hokkaido University, Graduate School of Engineering, Department of Mechanical Engineering (Doctoral course)
  • Apr. 1982 - Mar. 1984, Hokkaido University, Graduate School of Engineering, Department of Mechanical Engineering (Master Course)
  • Apr. 1978 - Mar. 1982, Hokkaido University, Faculty of Engineering, Department of Mechanical Engineering

Committee Memberships

  • Jul. 2024 - Present
    The Combustion Institute, Program Co-Chair (PCC), 41st International Symposium on Combustion, Society
  • Jan. 2024 - Present
    ISO(International Standard Organization)/TC244, Chair person, Others
  • Jul. 2020 - Present
    The Combustion Institute, Vice President, Society
  • Oct. 2014 - Present
    Science Council of Japan, Associate member, Government
  • Aug. 2014 - Present
    The Combustion Institute, Director, Society
  • Apr. 2009 - Sep. 2023
    Japan Aerospace Exploration Agency (JAXA), Committee for Space Utilization Science, Committee member (2022.2-2023.9 Chair）, Others
  • Jun. 2017 - Mar. 2021
    Japan Aerospace Exploration Agency (JAXA), Member of ISAS Steering Council, Government
  • Mar. 2017 - Mar. 2021
    Japan Society of Microgravity Application, President, Society
  • Apr. 2019 - Mar. 2020
    Japan Society for Mechanical Engineers, Vice President, Society
  • Jun. 2017 - Jun. 2019
    Combustion Society of Japan, President, Society
  • Apr. 2004 - Jun. 2019
    Combustion Society of Japan, Board of Directors, Society
  • Apr. 2017 - Mar. 2018
    Hokkaido University Division of Mehchanical and Space Engineering, Division Chair, Others
  • Apr. 2017 - Mar. 2018
    Japan Society of Mechanical Engineers, Thermal Engineering Division, Division Chair, Society
  • May 2015 - Apr. 2017
    Japan Aerospace Exploration Agency (JAXA), ISAS Committee for Space Engineering, Member, Government
  • Apr. 2016 - Mar. 2017
    Hokkaido University Faculty of Engineering, Chair, International Affairs Committee, Others
  • Apr. 2013 - Mar. 2017
    Hokkaido University, Planning and management office, Others
  • Mar. 2015 - Feb. 2016
    The Japan Society for Aeronautical and Space Sciences, Chair of Northern Branch, Society
  • Apr. 2010 - Mar. 2015
    Japan Society of Microgravity Application, Board of Directors, Society
  • Apr. 2008 - Mar. 2010
    Japan Society for Mechanical Engineers, Board of Directors, Society
  • 2006 - 2008
    The Japan Society for Aeronautical and Space Sciences, Division of Space Utilization, Chair, Society

■Research activity information

Awards

  • Mar. 2025, JSME(Japan Society for Mechanical Engineers), Hokkaido Branch, Contribution Award, JSME Hokkaido Branch　　　　　　　　　　　　　　　
    Achievements in thermal engineering, particularly in the field of combustion engineering, and contributions to the Hokkaido Branch
    Osamu Fujita
  • Nov. 2024, APS/DFD (The American Physical Society, Division of Fluid Dynamics), 2024 APS/DFD Gallery of Fluid Motion Award
    Transient parametric response of downward propagating premixed flames to self-induced thermoacoustic pressure waves
    Jerric Delfin;Nozomu Hashimoto;Osamu Fujita, 40646070
  • Nov. 2024, Fluid Science Foundation, Fluid Science Research Award　　　　　　　　　　　　　　　
    Research on Solid Material Flammability in Microgravity
    Osamu Fujita
  • Oct. 2024, Japan Society for Mechanical Engineers, Thermal Engineering Division, Thermal Engineering Award for International Activity　　　　　　　　　　　　　　　
    International leadership in the field of microgravity combustion research and contributions to combustion engineering from a fundamental perspective
    Osamu Fujita
  • Oct. 2023, Hokkaido University, Excellent Teacher Award　　　　　　　　　　　　　　　
    令和4年度全学教育科目
    Osamu Fujita
  • Feb. 2023, The Combustion Institute, 39th International Symposium on Combustion Distinguished Paper Award　　　　　　　　　　　　　　　
    Experimental study on downward/opposed flame spread and extinction over electric wires in partial gravity environments
    Yusuke Konno;Yutao Li;Jean-Marie Citerne;Guillaume Legros;Augustin Guibaud;Nozomu Hashimoto;Osamu Fujita
  • Nov. 2022, Combustion Society of Japan, 2022 Photo Contest -Beautiful Flames- The HIGHEST AWARD　　　　　　　　　　　　　　　
    Chrysanthemum Flame
    DELFIN, Jerric;GUO, Feng;HASHIMOTO, Nozomu;FUJITA, Osamu
  • Sep. 2022, The Japan Society of Microgravity Application, The Best Paper Award　　　　　　　　　　　　　　　
    Limiting Oxygen Concentration Trend of ETFE-Insulated Wires under Microgravity
    Ken MIZUTANI;Kyosuke MIYAMOTO;Nozomu HASHIMOTO;Yusuke KONNO;Osamu FUJITA
  • Nov. 2018, TANIKAWA FUND PROMOTION OF. THERMAL TECHNOLOGY, Komou Thermal Technology Award　　　　　　　　　　　　　　　
    Contribution to combustion engineering, specially research on combustion phenomena for industrial furnace
    FUJITA Osamu
  • Feb. 2018, The Combustion Institute, Fellow　　　　　　　　　　　　　　　
    FUJITA Osamu
  • Mar. 2015, The Japan Society for Aeronautical and Space Science, Fellow　　　　　　　　　　　　　　　
    FUJITA Osamu
  • Mar. 2015, Hokkaido University, President Award for Educational Contribution　　　　　　　　　　　　　　　
    Contribution to Hokkaido Universal Campus Initiative
    FUJITA Osamu
  • Dec. 2014, Combustion Society of Japan, 2014Phto Contest-Beautiful Flame- The Highest Award　　　　　　　　　　　　　　　
    Flame cake of the first birthday
    Sunghwan YOON;Taejoon NOH;Osamu FUJITA
  • Oct. 2013, Japan Society for Mechanical Engineers, Thermal Engineering Division, The 90th Term Research Achievement Award, Thermal Engineering Division　　　　　　　　　　　　　　　
    Research achievements in thermal engineering, particularly in the areas of soot formation in flames under microgravity conditions and solid combustion.
    Osamu Fujita
  • May 2013, Smart Processing Society for Materials, Environment & Energy (High Temperature Society), Best Reviewer Award, 2013　　　　　　　　　　　　　　　
    Research on the combustion of solid biomass -- Combustion characteristics of highly compressed biomass briquettes
    Hiroyuki Ito;Yuto Sakai;Takero Nakahara;Tamio Ida;Osamu Fujita
  • Apr. 2013, Japan Society of Mechanical Engineers (JSME), Fellow　　　　　　　　　　　　　　　
    FUJITA Osamu
  • Nov. 2012, Japan Society for Mechanical Engineers, Thermal Engineering Division, Best Presentation Award　　　　　　　　　　　　　　　
    Research on pyrolysis gas release characteristics from bio-cokes fuel
    Hiroyuki Ito;Yuto Sakai;Tamio Ida;Kaoru Wakatsuki;Osamu Fujita
  • Apr. 2007, Japan Society of Mechanical Engineers (JSME), Best paper award　　　　　　　　　　　　　　　
    A study on the Effect of Wall Temperature on Soot Deposition Process from a Diffusion Flame in Microgravity
    Osamu Fujita, Japan
  • Oct. 2006, The Japan Society of Microgravity Application, The Best Paper Award of the Japan Society of Microgravity Application　　　　　　　　　　　　　　　
    Combustion behavior of polyethylene insulated electric wire under low flow velocity in microgravity
    Osamu Fujita, Japan
  • Nov. 1999, Combustion Society of Japan, Award for young researchers, Combustion Society of Japan (1999.11)Best Flame Picture Award, Combustion Society of Japan, (2001.12)　　　　　　　　　　　　　　　
    Research on solid material flammability and soot formation utilizaing microgravity environment
    Osamu Fujita, Japan

Papers

Other Activities and Achievements

  • Solid Combustion Experiment on the ISS/Kibo-Progress in the FLARE Project-
    高橋周平, 鳥飼宏之, 小林芳成, 菊池政雄, 藤田修, 燃焼シンポジウム講演論文集(CD-ROM), 60th, 2022
  • Effect of heat transfer through wire core toward unburned region on the extinction of spreading flame over electric wires
    金野佑亮, 橋本望, 藤田修, 日本機械学会熱工学コンファレンス講演論文集(CD-ROM), 2020, 2020
  • Observation of downward flame spread phenomenon over electric wires with different insulation thickness
    蝋山大樹, 金野佑亮, 橋本望, 藤田修, 燃焼シンポジウム講演論文集(CD-ROM), 58th, 2020
  • Effect of the heat conduction along the core wire on the downward flame spread over an electric wire
    金野佑亮, 橋本望, 藤田修, 燃焼シンポジウム講演論文集(CD-ROM), 57th, 2019
  • Estimation of Blow-off Limit for Flame Spreading over Electric Wires in High Opposed Flow Field
    佐藤宏樹, 金野佑亮, 橋本望, 藤田修, 日本機械学会年次大会講演論文集(CD-ROM), 2019, 2019
  • Study on Flammability of Thermally Thick Insulated Wires: Effects of Insulation Thickness and Gravity Level on Flammability
    野一色郁武, 金野佑亮, 橋本望, 藤田修, 日本機械学会熱工学コンファレンス講演論文集(CD-ROM), 2019, 2019
  • Validation of the multi-component fuel droplet evaporation model in a laminar counterflow kerosene surrogate combustion field
    Nozomu Hashimoto, Yushin Naito, Kinya Saito, Jun Hayashi, Noriaki Nakatsuka, Fumiteru Akamatsu, Osamu Fujita, 12th Asia-Pacific Conference on Combustion, ASPACC 2019, 01 Jan. 2019
  • Effect of Le on transition to parametric instability in downward propagating flames
    Ajit Kumar Dubey, Yoichiro Koyama, Sung Hwan Yoon, Nozomu Hashimoto, Osamu Fujita, 12th Asia-Pacific Conference on Combustion, ASPACC 2019, 01 Jan. 2019
  • Opposed-flow flame spread over thin electric wires
    Yusuke Konno, Nozomu Hashimoto, Osamu Fujita, 12th Asia-Pacific Conference on Combustion, ASPACC 2019, 01 Jan. 2019
  • Experimental Comparison on Transition Criteria to Parametric Instability of a Downward-propagating Flame in a Tube Induced by Single Laser Irradiation and Double Laser Irradiation
    Nguyen Truong Gia Tri, Nozomu Hashimoto, Osamu Fujita, 12th Asia-Pacific Conference on Combustion, ASPACC 2019, 01 Jan. 2019
  • Influence of three lithium salts on the flame behaviors and extinction limits of dimethyl carbonate-based electrolytes using a wick combustion method
    Feng Guo, Yu Ozaki, Katsunori Nishimura, Nozomu Hashimoto, Osamu Fujita, 12th Asia-Pacific Conference on Combustion, ASPACC 2019, 01 Jan. 2019
  • Development and validations of droplet evaporation model for low ignitibility fuel considering inner distributions under atmospheric pressure
    Yushin Naito, Nozomu Hashimoto, Osamu Fujita, 12th Asia-Pacific Conference on Combustion, ASPACC 2019, 01 Jan. 2019
  • Validation of multi-component fuel droplet evaporation model for laminar counter flow kerosene spray flame
    橋本望, 内藤雄心, 齋藤欣也, 林潤, 中塚記章, 赤松史光, 藤田修, 燃焼シンポジウム講演論文集, 56th, ROMBUNNO.D322, 14 Nov. 2018
    Japanese
  • Verification of Multicomponent Fuel Droplet Evaporation model for Kerosene under Various Ambient Temperature
    内藤雄心, 上田健五, ALEXIS Lefevre, 橋本望, 菅沼祐介, 野村浩司, 藤田修, 燃焼シンポジウム講演論文集, 56th, ROMBUNNO.D311, 14 Nov. 2018
    Japanese
  • Effect of Ambient Pressure on Spreading over Wire Insulation under Opposed Flow Condition in Microgravity
    永地大志, 三井郁矢, CITERNE Jean‐Marie, DUTILLEUL Hugo, GUIBAUD Augustin, JOMAAS Grunde, JOMAAS Grunde, LEGROS Guillaume, 橋本望, 藤田修, 燃焼シンポジウム講演論文集, 56th, ROMBUNNO.D334, 14 Nov. 2018
    Japanese
  • 微小重力下における電線被覆上を燃え拡がる火炎の温度に関する検討
    都築克弥, 金野佑亮, 佐藤宏樹, 橋本望, 藤田修, 日本火災学会研究発表会概要集, 2018, 82‐83, 29 May 2018
    Japanese
  • Downward flame spread and extinction phenomena of externally heated electric wire: Effect of materials geometry and opacity on its flammability
    金野佑亮, 野一色郁武, 橋本望, 藤田修, 日本機械学会熱工学コンファレンス講演論文集(CD-ROM), 2018, 2018
  • 数値解析によるポリエチレン被覆電線上燃え拡がり火炎の限界酸素濃度における熱バランス評価
    会田裕樹, 橋本望, 藤田修, 日本伝熱シンポジウム講演論文集(CD-ROM), 55th, ROMBUNNO.A221, 2018
    Japanese
  • 微小重力環境下における並行空気流中の電線被覆上燃え拡がり火炎の観察
    永地大志, 三井郁矢, CITERNE Jean‐Marie, DUTILLEUL Hugo, GUIBAUD Augustin, JOMAAS Grunde, LEGROS Guillaume, 橋本望, 藤田修, 日本伝熱シンポジウム講演論文集(CD-ROM), 55th, ROMBUNNO.A222, 2018
    Japanese
  • Opposed-flow flame spread over electric wire: The effect of ambient oxygen concentration on flame size and flame spread rate
    金野佑亮, 都築克弥, 橋本望, 藤田修, 燃焼シンポジウム講演論文集, 55th, 66‐67, 13 Nov. 2017
    Japanese
  • Preheating effect on the extinction limit for a flame spreading over polyethylene coated wire
    三井郁矢, CITERNE Jean‐Marie, DUTILLEUL Hugo, JOMAAS Grunde, GUILLAUME Legros, 橋本望, 藤田修, 燃焼シンポジウム講演論文集, 55th, 464‐465, 13 Nov. 2017
    Japanese
  • Prediction of Soot Formation in Pulverized Coal Combustion field of 0.5kg/coal/h pulverized coal jet burner by Large Eddy Simulation Employing the TDP model.
    高橋弥楊, 橋本望, 渡邊裕章, 黒瀬良一, 藤田修, 燃焼シンポジウム講演論文集, 55th, 446‐447, 13 Nov. 2017
    Japanese
  • Numerical Investigation on Extinction Phenomena of Flame Spreading over Polyethylene Insulated Wire in Microgravity
    会田裕樹, 橋本望, 藤田修, 燃焼シンポジウム講演論文集, 55th, 534‐535, 13 Nov. 2017
    Japanese
  • 乱れ強さおよび粒子濃度が球状に伝播する微粉炭火炎に及ぼす影響
    市村涼, KHALID Hadi Bin, 橋本望, 藤田修, 化学工学会秋季大会研究発表講演要旨集(CD-ROM), 49th, ROMBUNNO.EB123, 20 Sep. 2017
    Japanese
  • 分解軽油(LCO)液滴の蒸発特性に関する実験的研究
    内藤雄心, 橋本望, 高木正英, 川内智詞, 今井康雄, 三ツ井裕太, 青木剛, 林利昭, 野村浩司, 菅沼祐介, 藤田修, 日本機械学会北海道支部講演会講演概要集(CD-ROM), 55th, ROMBUNNO.432, 18 Sep. 2017
    Japanese
  • 微小重力下における熱的に厚い電線被覆上を燃え拡がる火炎の消炎限界の推定
    宮本恭輔, 金野佑亮, 橋本望, 藤田修, 日本火災学会研究発表会概要集, 2017, 178‐179, 20 May 2017
    Japanese
  • Flame spread and dripping behaviors in horizontal and vertical wires
    Y. Kobayashi, X. Huang, Y. Konno, S. Nakaya, M. Tsue, N. Hashimoto, O. Fujita, C. Fernandez-Pello, 10th U.S. National Combustion Meeting, 2017-April, 2017
  • Experimental Study of Evaporation Characteristics of Low Ignitibility Fuel Droplet at High Temperatures and Pressures
    Naito Yushin, Hashimoto Nozomu, Takagi Masahide, Kawauchi Satoshi, Imai Yasuo, Mitsui Yuta, Aoki Go, Hayashi Toshiaki, Nomura Hiroshi, Suganuma Yusuke, Fujita Osamu, The Proceedings of Mechanical Engineering Congress, Japan, 2017, 0, 2017
    <p>It is needed to greatly modify fuel component because of strengthened sulfur component regulations in fuel oil for ships by IMO (International Maritime Organization). Light Cycle Oil (LCO) which contains less sulfur component has been focused as a base fuel. The increase of the LCO mixing ratio in fuels for diesel engines is expected in the future. Evaporation characteristics which are one of a physical process in spray combustion affect flame stabilities and combustion emissions. The objective of this study is to clarify the relationships between evaporation characteristics and fuel characteristics of LCO by conducting evaporation experiments of LCO. The evaporation experiments of LCO were conducted by single LCO droplets at various ambient temperatures (473~873 K) and pressures (0.1, 0.5, 1.0 MPa). Moreover, the evaporation characteristics of 5 types LCO were compared to clarify how the fuel properties affect the evaporation characteristics. As a result, it was found that the difference of the droplet lifetimes between fuels is large at low ambient temperature. This is because high boiling components in LCO make the droplet lifetimes of LCO longer from the middle to the late of evaporation. The pressure dependence of evaporation coefficient of some LCO at high ambient temperature was different from that of single component fuel. This is possibly caused by effect of multicomponent of LCO on the behavior of the evaporation coefficients.</p>, The Japan Society of Mechanical Engineers, Japanese
  • Dimensional Analysis for Flammability Limits of Spreading Flame over Electric Wire in Microgravity
    KONNO Yusuke, TSUZUKI Katsuya, HASHIMOTO Nozomu, FUJITA Osamu, The Proceedings of Mechanical Engineering Congress, Japan, 2017, 0, G0600105, 2017
    <p>An attempt to develop a scale model to estimate extinction limits of spreading flame over electric wires in opposed flow under microgravity has been made. Ethylene tetrafluoroethylene (ETFE) insulated copper (Cu) wire is chosen as the sample wire because of the availability of its experimental data. The results showed that the estimated extinction limits given by the scale model developed in the present work corresponded well with experimental results qualitatively. However, further modifications of individual sub-models are expected to provide quantitative estimation.</p>, The Japan Society of Mechanical Engineers, Japanese
  • No.2-8 Experimental Study on Effect of Turbulence Intensity on Spherical Turbulent Flame Propagation of Pulverized Coal Particle Cloud
    橋本望, KHALID Hadi Bin, 市村涼, 藤田修, 日本エネルギー学会石炭科学会議発表論文集(Web), 54, 68‐69(J‐STAGE), 2017
    Japanese
  • 周囲空気流速が電線被覆上燃え拡がり火炎の消炎現象に与える影響の数値解析による考察
    会田裕樹, 橋本望, 藤田修, 日本伝熱シンポジウム講演論文集(CD-ROM), 54th, ROMBUNNO.A211, 2017
    Japanese
  • 異なる心線材質を持つ電線被覆上燃え拡がり火炎の消炎限界に及ぼす初期着火条件の影響
    三井郁矢, 永地大志, CITERNE Jean‐Marie, DUTILLEUL Hugo, JOMAAS Grunde, LEGROS Guillaume, 橋本望, 藤田修, 日本伝熱シンポジウム講演論文集(CD-ROM), 54th, ROMBUNNO.A135, 2017
    Japanese
  • The Effect of Ambient Gases on Evaporation Characteristics of n-Hexadecane Droplet under High Pressure
    佐藤 佑衣子, 内藤 雄心, 橋本 望, 村越 好泰, 菅沼 祐介, 野村 浩司, 藤田 修, 微粒化シンポジウム講演論文集, 25, 217, 222, 19 Dec. 2016
    日本液体微粒化学会, Japanese
  • 微小重力場におけるポリエチレン被覆電線上燃え拡がり火炎消炎限界の対向流と並行流における比較
    永地大志, 三井郁矢, 橋本望, 藤田修, 燃焼シンポジウム講演論文集, 54th, B313, 26 Nov. 2016
    Japanese
  • 微小重力場における被覆導線の通電着火現象に対する被覆厚さ影響
    清水晃平, 藤田修, 橋本望, 菊池政雄, 燃焼シンポジウム講演論文集, 54th, B312, 26 Nov. 2016
    Japanese
  • 熱的に厚い模擬電線被覆上を燃え拡がる火炎の消炎現象に関する検討
    宮本恭輔, 金野佑亮, HUANG Xinyan, FERNANDEZ‐PELLO Carlos, 橋本望, 藤田修, 燃焼シンポジウム講演論文集, 54th, B314, 26 Nov. 2016
    Japanese
  • 微小重力場における被覆導線の過電流連続通電時の着火限界に関する数値的検討
    清水晃平, 橋本望, 菊池政雄, 藤田修, 日本機械学会年次大会講演論文集(CD-ROM), 2016, ROMBUNNO.G0600504, 10 Sep. 2016
    Japanese
  • 電線被覆上燃え拡がり火炎の消炎限界に及ぼす外部輻射の影響
    宮本恭輔, 水谷拳, 金野佑亮, HUANG Xinyan, FERNANDEZ‐PELLO Carlos, 橋本望, 藤田修, 日本火災学会研究発表会概要集, 2016, 32‐33, 11 May 2016
    Japanese
  • Flammability limit of polyethylene insulated wires under varying oxygen concentration and external radiation
    Kyosuke Miyamoto, Xinyan Huang, Nozomu Hashimoto, Carlos Fernandez-Pello, Osamu Fujita, 2016 Spring Technical Meeting of the Western States Section of the Combustion Institute, WSSCI 2016, 01 Jan. 2016
  • 5-1-2 Application of TDP model to Unsteady Numerical Simulation for Lab-Scale Pulverized Coal Burner
    TAKAHASHI Hiroyasu, HASHIMOTO Nozomu, WATANABE Hiroaki, KUROSE Ryoichi, FUJITA Osamu, Proceedings of the Annual Conference of The Japan Institute of Energy, 25, 0, 142, 143, 2016
    <p>In pulverized coal combustion, it is generally known that coal particle's heating rate affects its devolatilization behavior. In previous research conducted by N. Hashimoto et al, TDP (Tabulated Devolatilization Process) Model [1] which enables to take heating rate effects into account by using devolatilization database was suggested. TDP model has already applied for steady numerical simulation. However, it has not yet applied for unsteady numerical simulation. In this research, therefore, TDP model was applied to unsteady simulation. To investigate its validity, numerical simulation for lab-scale pulverized coal burner was performed. As its application results, coal particle's heating rate is calculated for each particle size and extraction of appropriate devolatilization parameter from the database is done. In addition, location of calculated particles with high temperature distribution was in good agreement with experimental direct photograph's luminous flame position.</p>, 一般社団法人 日本エネルギー学会, Japanese
  • 電線被覆上燃え拡がり火炎の消炎限界に及ぼす初期着火条件の影響
    三井郁矢, 永地大志, CITERNE Jean‐Marie, DUTILLEUL Hugo, JOMAAS Grunde, LEGROS Guillaume, 橋本望, 藤田修, 日本機械学会熱工学コンファレンス講演論文集(CD-ROM), 2016, ROMBUNNO.D123, 2016
    Japanese
  • 微小重力場における被覆電線の連続通電着火現象に対する数値的検討
    SHIMIZU KOHEI, FUJITA OSAMU, HASHIMOTO NOZOMU, KIKUCHI MASAO, 燃焼シンポジウム講演論文集, 53rd, 500, 501, 04 Nov. 2015
    Japanese
  • 微小重力下における電線被覆上燃え拡がり火炎の消炎限界推定モデルの検討
    MIZUTANI KEN, MIYAMOTO KYOSUKE, HASHIMOTO NOZOMU, FUJITA OSAMU, 燃焼シンポジウム講演論文集, 53rd, 502, 503, 04 Nov. 2015
    Japanese
  • D131 Difference of Extinction Limit of Spreading Flame over Polyethylene Insulated Wire between Opposed Air Flow and Concurrent Air Flow
    Nagachi Masashi, Yoshioka Kosuke, Hashimoto Nozomu, Fujita Osamu, Procee[d]ings of Thermal Engineering Conference, 2015, "D131, 1"-"D131-2", 23 Oct. 2015
    Tests with flames spreading over wires in microgravity were performed at external opposed flow and concurrent flow conditions to examine the influence of flow direction on the extinction limit. In the experiments, low density polyethylene insulated Nickel-chrome and Copper wire samples were used. The experiments were conducted both in normal gravity and microgravity. Limiting Oxygen concentration (LOC) of microgravity is lower than that of normal gravity because of inhibited natural convection. LOC of Nickel-chrome is lower than that of Copper because of difference of heat conduction loss. The minimum LOC of concurrent flow is smaller than that of opposed flow in the range of 1-2%., The Japan Society of Mechanical Engineers, Japanese
  • Research on Instability of Propagating Flames in a Combustion Tube by using Laser Irradiation Method
    FUJITA Osamu, J.Combustion Society of Japan, 57, 181, 174, 182, Aug. 2015, [Invited]
    日本燃焼学会, Japanese, Introduction scientific journal
  • FLAREプロジェクトにおける電線燃焼研究の状況
    FUJITA OSAMU, MIZUTANI KEN, MIYAMOTO KYOSUKE, YOSHIOKA KOSUKE, HASHIMOTO NOZOMU, 宇宙科学技術連合講演会講演集(CD-ROM), 59th, ROMBUNNO.3E04, 2015
    Japanese
  • 微小重力環境における電線試料の消炎限界酸素濃度低下に対する被覆材料影響
    MIZUTANI KEN, MIYAMOTO KYOSUKE, HASHIMOTO NOZOMU, FUJITA OSAMU, 日本伝熱シンポジウム講演論文集(CD-ROM), 52nd, ROMBUNNO.B221, 2015
    Japanese
  • Introduction of Research Projects on Solid Material Combustion utilizing ISS/Kibo and Their Expected Outcome
    藤田 修, 日本燃焼学会誌, 56, 176, 117, 124, May 2014, [Invited]
    日本燃焼学会, Japanese, Introduction scientific journal
  • Overview of "Solid Combustion" experiment in the ISS/KIBO
    Takanari Mizushima, Masao Kikuchi, Masahiro Takayanagi, Hiroyuki Torikai, Akihiko Ito, Shuhei Takahashi, Osamu Fujita, Proceedings of the International Astronautical Congress, IAC, 1, 718, 723, 01 Jan. 2014
  • 短時間微小重力環境を利用した固体材料の燃焼性に関する研究　　　　　　　　　　　　　　　
    藤田 修, International Journal of Microgravity Science Application, 31, 1, 31, 37, Jan. 2014, [Invited]
    Japanese, Introduction scientific journal
  • Ignition and Combustion Characteristics of Highly Densified Biomass Briquette
    Ito Hiroyuki, Ida Tamio, Fujita Osamu, 神奈川大学工学研究所所報, 36, 16, 21, Nov. 2013
    総説, 神奈川大学工学研究所, Japanese
  • A113 Ignition of Electric Wire Insulation Caused by Continuous Excess Current Supply in Microgravity
    Fujita Osamu, Shigeta Naoki, Procee[d]ings of Thermal Engineering Conference, 2013, 5, 6, 18 Oct. 2013
    Ignition tests of overloaded electric wire were carried out in microgravity provided by airplane parabolic flight. Polyethylene insulated NiCr core wire (inner core diameter 0.5 and outer diameter 0.8 mm) was used as a test sample. The results showed that the ignition limit in terms of supplied electric power dramatically decreased with increase in microgravity time. It was suggested that the total electric energy supplied to the wire gave the primary criteria for ignition, which was consistent with experimental findings. Further, the importance of conductive heat loss to the surroundings was pointed out for very low electric current condition according to the simple one-dimensional numerical calculation., The Japan Society of Mechanical Engineers, Japanese
  • B134 Influence of the condition of non-equilibrium plasma application on the yield of cellulose pyrolysis products
    Ito Hiroyuki, Endo Shota, Kambara Shinji, Fujita Osamu, Procee[d]ings of Thermal Engineering Conference, 2013, 61, 62, 18 Oct. 2013
    The influence of non-equilibrium Ar plasma on the composition of tar obtained by cellulose pyrolysis was investigated. When Ar plasma is given to the cellulose pyrolysis from the beginning of the experiments (from room temperature), the collected tar composition is almost the same with no plasma condition. In the case plasma is given after furnace temperature becomes higher than 300℃, the rate of furfural in the collected tar increases and the rate of levoglucosan decreases. From the results, it is suggested that decrease in decomposition temperature or increase in pyrolysis rate is caused by applying non-equilibrium Ar plasma to the cellulose pyrolysis., The Japan Society of Mechanical Engineers, Japanese
  • I213 Influence of non-equilibrium Ar plasma on the yield of cellulose pyrolysis product
    Ito Hiroyuki, Neoi Wataru, Kambara Shinji, Fujita Osamu, Procee[d]ings of Thermal Engineering Conference, 2012, 477, 478, 16 Nov. 2012
    The influence of non-equilibrium Ar plasma on the yield and composition of cellulose pyrolysis product is investigated. Dielectric barrier discharge (DBD) is used to obtain Ar plasma. The amount of products (gas, collected tar and residual char) are determined and the composition of the collected tar is analyzed by GC-MS. Gas yield decreases and the collected tar in the low temperature range increases with plasma, whereas the temperature in the pyrolysis furnace may change little. It is also suggested that applying plasma may change the reaction pathway of cellulose decomposition because the composition of collected tar has the different tendency to that observed with the temperature increase., The Japan Society of Mechanical Engineers, Japanese
  • 403 Comparison of thermodynamical potentials of oxy-fuel combustion and conventional air-combustion
    Sato Kenichi, Fujita Osamu, 北海道支部講演会講演概要集, 2012, 51, 117, 118, 20 Oct. 2012
    The Japan Society of Mechanical Engineers, Japanese
  • Pb-206 Investigation on ignition and subsequent combustion of BIG (Bio-coke) block
    ITO Hiroyuki, NAKAHARA Takero, SAKAI Yuto, IDA Tamio, FUJITA Osamu, Proceedings of the Conference on Biomass Science, 0, 7, 150, 151, 18 Jan. 2012
    Fundamental thermal and combustion properties of the Bio-coke (BIC) have been investigated. At first ignition and combustion behaviors are observed in the hot air flow. The results show that the ignition mode and the mass loss rate during the flaming combustion are influenced by the supplied air temperature with an interesting manner. This may be ascribed to the thickness of the heated layer inside the BIC depending on the preheating condition. A new concept of BIC combustion method, called "end face combustion", is proposed considering the BIC unique physical features as well as its fundam..., The Japan Institute of Energy, Japanese
  • Numerical Simulation of the Pyrolysis of Solid Waste in an Externally Heated Rotary Kiln
    岡崎輝幸, 鈴木朋子, 山本研二, 仲田博幸, 藤田修, 大島伸行, 日本機械学会論文集 B編(Web), 78, 786, 2012
  • Formation characteristics of high-density and high-hardness new briquette based on herby biomass
    Satoru Mizuno, Tamio Ida, Manabu Fuchihata, Kunihiko Namba, Atsushi Kakosaka, Osamu Fujita, Nihon Enerugi Gakkaishi/Journal of the Japan Institute of Energy, 91, 1, 41, 47, 2012
    Japanese
  • I213 Considerations on gas evolution from the bio-coke fuel caused by heating
    Ito Hiroyuki, Sakai Yuto, Ida Tamio, Wakatsuki Kaoru, Fujita Osamu, Procee[d]ings of Thermal Engineering Conference, 2011, 383, 384, 28 Oct. 2011
    The evolution characteristics of degradation gas from highly densified biomass briquette called Bio-coke (BIC) are experimentally and numerically investigated. In the present study, evolution rates of both volatile and water from the sample are determined as Arrhenius-type equations and the constants such as frequency factors and activation energies are given by the thermo-gravimetric analysis. It is confirmed that the model used in the study can qualitatively describe the gas evolution from the BIC sample. With high water content, the time volatile evolution start is delayed because much heat is consumed to evaporate the water. In the period before the volatile evolution start, the rate of evolved water to the whole water increases with increasing the water content of the BIC sample., The Japan Society of Mechanical Engineers, Japanese
  • G060034 Investigation on the characteristics of pyrolysis gas evolution from BIC (Bio-coke) fuel
    ITO Hiroyuki, SAKAI Yuto, IDA Tamio, WAKATSUKI Kaoru, FUJITA Osamu, Mechanical Engineering Congress, Japan, 2011, "G060034, 1"-"G060034-5", 11 Sep. 2011
    The evolution characteristics of degradation gas from highly densified biomass briquette called Bio-coke (BIC) are experimentally and numerically investigated. In the present study, evolution rates of both volatile and water from the BIC sample are determined by Arrhenius equations and the constants such as frequency factors and activation energies are given by the experimental results of thermo-gravimetric analysis. It is confirmed that the analysis model used in the study can qualitatively describe the gas evolution from the BIC sample. Rapid increase in the gas evolution rate is identified when the BIC sample ( 0 20 mm x 10 mm) is heated at an end face of the sample. This can be attributed to the finite volume of the BIC sample; the rapid temperature increase can be observed after the water in the sample is completely released. The volatile/water ratio in the evolution gas takes constant value at heat flux higher than 50 kW/m2 while the ratio gradually increases with time at the low heat flux case (25 kW/m2)., The Japan Society of Mechanical Engineers, Japanese
  • 7-327 Internship Student Exchange with ENSMA in France and its Contribution to Student Education
    FUJITA Osamu, 工学教育研究講演会講演論文集, 23, 59, 622, 623, 22 Aug. 2011
    Japanese Society for Engineering Education, Japanese
  • 高圧縮固体バイオマス燃料の燃料利用
    伊東弘行, 酒井雄人, 井田民男, 藤田修, 日本燃焼学会誌, 53, 164, 63, 68, May 2011, [Invited]
    Japanese, Introduction scientific journal
  • 微小重力環境を利用した固体燃焼現象研究(H22研究班WG報告)
    藤田修, 中村祐二, 永田晴紀, 菊池政雄, 伊藤昭彦, 鳥飼宏之, 梅村章, 高橋周平, 池田光優, CHUNG Suk Ho, OLSON Sandra L, 宇宙利用シンポジウム, 27th, 31, 32, Mar. 2011
    第27回宇宙利用シンポジウム (2011年1月24日-25日, 宇宙航空研究開発機構宇宙科学研究所相模原キャンパス), 相模原市, 神奈川県
    The Twenty-seventh Space Utilization Symposium (January 24-25, 2011. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan
    Since solid combustion is dominated by diffusion process of pyrolyzed gas as well as heat transfer process around the combustion region, flammability limit becomes very different depending on the gravitational conditions. In the present work, an attempt to know the mechanism of the extension of ignition limit of overloaded wire has been made by numerical calculation. The results showed that the Joule energy more than a critical value causes release of degradation gas and its ignition, and the critical value becomes smaller in microgravity than that in normal gravity. Further, the preparation status of the ISS experiment including the wire ignition and flame spread over solid material is introduced.
    著者人数: 11人
    形態: カラー図版あり
    Number of authors: 11
    Physical characteristics: Original contains color illustrations
    資料番号: AA0065129013, 宇宙航空研究開発機構宇宙科学研究所 (JAXA)(ISAS), Japanese
  • ISS日本実験棟における固体材料燃焼研究（Solid Combustion）　　　　　　　　　　　　　　　
    藤田 修, 日本マイクログラビティ応用学会誌, 28, 3, 90, 95, 2011, [Invited]
    Japanese, Introduction scientific journal
  • 309 The Effect of Electric Field on Single-Walled Carbon Nanotube in Flame Method
    ONISHI Akira, MASUNAGA Kota, FUJITA Osamu, NAKAMURA Yuji, ITO Hiroyuki, 北海道支部講演会講演概要集, 2010, 49, 67, 68, 07 Nov. 2010
    The Japan Society of Mechanical Engineers, Japanese
  • D113 Effect of ambient pressure on consumption rate of melting polyethylene coated over electric wire
    Iwakami Junya, Nakamura Yuji, Wakatsuki Kaoru, Ito Hiroyuki, Fujita Osamu, Procee[d]ings of Thermal Engineering Conference, 2010, 0, 93, 94, 29 Oct. 2010
    Flame spread behavior over electric wire coated polyethylene (PE) in low pressure is studied experimentally. The objective of this study is to investigate the relationship between consumption rate of melting PE and ambient pressure. The ambient gas composition is fixed to the same as air and total pressure is set to sub-atmospheric range (30〜100 kPa). Dynamic behavior of molten PE under various conditions is precisely observed/recorded in order to analyze the growth rate of molten PE and increment of spread rate in time with various types of wires. It turns out that the growth rates in the ..., The Japan Society of Mechanical Engineers, Japanese
  • E213 Ignition and combustion behavior of bio-coke fuel placed in high temperature air flow
    Ito Hiroyuki, Sakai Yuto, Fujita Osamu, Nakamura Yuji, Ida Tamio, Procee[d]ings of Thermal Engineering Conference, 2010, 0, 319, 320, 29 Oct. 2010
    Ignition and combustion characteristics of Bio-coke (BIC, highly densified biomass briquette) in high temperature air flow have been investigated. In the present study, ignition behavior is observed, and the mass loss rates for flaming combustion and surface combustion are measured. The experimental results showed that the surface ignition precedes gas-phase ignition in the case of high temperature air, while surface ignition and gas-phase ignition simultaneously occur in the case of low temperature air. Consequently, it is suggested that the temperature distribution inside BIC, i.e. the pr..., The Japan Society of Mechanical Engineers, Japanese
  • G0600-8-5 Effects of DC Electric Field on Carbon Nanotube Synthesis
    MASUNAGA Kohta, ONISHI Akira, ITO Hiroyuki, NAKAMURA Yuji, FUJITA Osamu, The proceedings of the JSME annual meeting, 2010, 3, 209, 210, 04 Sep. 2010
    The purpose of this study is to reveal the effects of DC electric field on carbon nanotube (CNT) synthesis. In flame synthesis method, it is considered that there are two effects of DC electric field which promotes CNT growth; i.e. generating ionic wind and enhancing catalytic activity. To distinguish the effect of DC bias on catalytic activity promotion, chemical vapor deposition (CVD) synthesis with high voltage DC bias is used in the present study. DC bias voltage is varied from -1.0 kV to +1.0 kV. It is confirmed that CNT growth is promoted by applying electric field. Moreover, it is su..., The Japan Society of Mechanical Engineers, Japanese
  • 微小重力環境を利用した固体燃焼現象研究 (H21研究班WG報告)—Solid Combustion Research in Microgravity（2009 Research WG Report
    藤田, 修, 中村, 祐二, 永田, 晴紀, 菊池, 政雄, 伊藤, 昭彦, 鳥飼, 宏之, 梅村, 章, 高橋, 周平, 池田, 光優, Fujita, Osamu, Nakamura, Yuji, Nagata, Harunori, Kikuchi, Masao, Ito, Akihiko, Torikai, Hiroyuki, Umemura, Akira, Takahashi, Shuhei, Ikeda, Mitsumasa, Chung, Suk Ho, 宇宙利用シンポジウム = Space Utilization Research: Proceedings of Space Utilization Symposium, 26, Feb. 2010
    第26回宇宙利用シンポジウム(2010年1月25日-26日, 宇宙航空研究開発機構宇宙科学研究本部相模原キャンパス)
    The Twenty-sixth Space Utilization Symposium (January 25-26, 2010: ISAS/JAXA Sagamihara, Japan)
    Since solid combustion is dominated by diffusion process of pyrolyzed gas as well as heat balance around combustion area, flammability limit becomes very different depending on the gravitational conditions. In the present work, the attempt to obtain ignition limit for overloaded electric wire and extinction limits for spreading flame over flat sheet has been made under the limit of 4.5 sec microgravity time provided by MGLAB. According to the experiments, it is found that the flammable limits, ignition and extinction limits, significantly extend in microgravity in comparison with those in normal gravity.
    形態: カラー図版あり
    共催: 日本学術会議
    Physical characteristics: Original contains color illustrations
    joint hosting: The Science Council of Japan
    資料番号: AA0064730020, 宇宙航空研究開発機構宇宙科学研究本部, Japanese
  • 510 Unsteady phenomenon of spreading flame over wire insulation under microgravity
    ONISHI Yosuke, TAKEUCHI Hiroyuki, FUJITA Osamu, ITO Hiroyuki, NAKAMURA Yuji, 北海道支部講演会講演概要集, 2009, 48, 155, 156, 28 Nov. 2009
    The Japan Society of Mechanical Engineers, Japanese
  • B112 Observation of Ignition Process of Bio-coke Fuel Placed in High Temperature Air
    Ito Hiroyuki, Sakai Yuto, Fujita Osamu, Nakamura Yuji, Ida Tamio, Procee[d]ings of Thermal Engineering Conference, 2009, 0, 33, 34, 06 Nov. 2009
    Bio-coke, one of biomass fuels, is expected as a substitution to fossil fuel to prevent global warming as well as the other biomass energy. In this study, we investigate combustion characteristics of bio-coke in high temperature airflow, especially for ignition processes, which is not widely-known. Japanese knotweed is chosen as an ingredient of bio-coke. The gas temperature near the sample is measured by thermo-couple, the surface temperature of bio-coke is monitored by IR camera and the reduction of weight is scaled by a balance. It is identified that there are two types of ignition mode ..., The Japan Society of Mechanical Engineers, Japanese
  • T0501-4-7 A Study on Wire Insulation Ignition Induced by Short-term Excess Electric Current Application by using Microgravity Condition
    KYONO Takeshi, FUJITA Osamu, KIDO Yasuhiro, NAKAMURA Yuji, ITO Hiroyuki, The proceedings of the JSME annual meeting, 2009, 8, 143, 144, 12 Sep. 2009
    Ignition behavior of overloaded electric wire is investigated under various gravitational conditions to know the impact of surrounding flow field on the ignition process. The experimental parameters are oxygen concentration, supplied electric current value and the applied time. The result shows that the ignition phenomenon easily occurs in non-convective flow field (in microgravity), which is characterized by lower limit of electric current to attain ignition. Moreover, as a result of the observation by Mach-Zehnder interferometry, due to a distinguished difference of pyrolysis gas motions ..., The Japan Society of Mechanical Engineers, Japanese
  • F218 An Improvement of Start-up Characteristics of DME Catalytic Combustor for Mobile Use
    Fujita Osamu, Tameda Kazuma, National Symposium on Power and Energy Systems, 2009, 14, 511, 512, 28 Jun. 2009
    This study investigates low temperature startability of dimethyl-ether (DME) catalytic combustor as a small size heat generator. A procedure of DME pre-supply followed by mixture supply into the reactor shows great improvement of startability. With this procedure catalyst surface temperature increases caused by DME adsorption heat at the period of DME pre-supply and increased temperature promote catalytic reaction. When the period of DME pre-supply is excess, the reactor temperature turns decrease by increased heat loss in comparison with adsorption heat. The mechanism to appear the optimum condition of DME pre-supply to attain the best startability of DME catalytic combustor is discussed based on the DME adsorption characteristics to the catalyst surface., The Japan Society of Mechanical Engineers, Japanese
  • 微小重力環境を利用した固体燃焼現象研究（H20研究班WG報告）—Solid combustion research in microgravity (2008 Research WG Report)
    藤田, 修, 中村, 祐二, 永田, 晴紀, 菊池, 政雄, 伊藤, 昭彦, 鳥飼, 宏之, 梅村, 章, 高橋, 周平, 池田, 光優, Fujita, Osamu, Nakamura, Yuji, Nagata, Harunori, Kikuchi, Masao, Ito, Akihiko, Torikai, Hiroyuki, Umemura, Akira, Takahashi, Shuhei, Ikeda, Mitsumasa, Chung, Suk Ho, 宇宙利用シンポジウム = Space Utilization Research: Proceedings of Space Utilization Symposium, 25, Mar. 2009
    第25回宇宙利用シンポジウム(2009年1月14日-15日, 宇宙航空研究開発機構宇宙科学研究本部相模原キャンパス)
    The Twenty-fifth Space Utilization Symposium (January 14-15, 2009: ISAS/JAXA Sagamihara, Japan)
    Since solid combustion is dominated by diffusion process of pyrolyzed gas as well as heat balance around combustion area, which are strongly affected by convective flow, micorgravity could be an effective tool to understand its mechanism. One of the most important contributions of solid combustion research in microgravity is fire safety in space. In the present report, some researches on going regarding fire safety in space will be introduced.
    資料番号: AA0064297124, 宇宙航空研究開発機構宇宙科学研究本部, Japanese
  • 411 Measurement of Products from DME Catalytic Combustion Operated in Fuel-Rich Condition
    Tsukanaka Daisuke, Tameda Kazuma, Fujita Osamu, Nakamura Yuji, Ito Hiroyuki, 北海道支部講演会講演概要集, 2008, 47, 105, 106, 27 Sep. 2008
    The Japan Society of Mechanical Engineers, Japanese
  • 412 Effect of Gravity Condition on Wire Insulation Ignition : Observation of Ignition Phenomena in Normal Gravity
    KYONO Takeshi, FUJITA Osamu, KIDO Yasuhiro, NAKAMURA Yuji, ITO Hiroyuki, 北海道支部講演会講演概要集, 2008, 47, 107, 108, 27 Sep. 2008
    The Japan Society of Mechanical Engineers, Japanese
  • Activities of Hokkaido Applied Combustion Research Group
    FUJITA Osamu, 日本燃焼学会誌 = Journal of the Combustion Society of Japan, 50, 153, 174, 175, 15 Aug. 2008
    Japanese
  • 実験力学ハンドブック　　　　　　　　　　　　　　　
    朝倉書店, 2008, [Invited]
  • Comparison of Soot Formation Characteristics between DME Diffusion Flame and the Partially Premixed Methane Flame
    Masanori KOBAYASHI, Ryosuke IMAI, Osamu FUJITA, Transaction of JSME, 74, 748, 2718, 2723, 2008
  • Effects of Radiation Feedback on Flame Spread along Polymer-Insulated Wire in Microgravity
    Journal of the Combustion Society of Japan, 50, 153, 255, 263, 2008
  • Attainment of Luminous DME Spray Flame by Controlling Air Mixing at the Flame Base
    Journal of the Combustion Society of Japan, 50, 153, 264, 270, 2008
  • E223 Improvement of Low Temperature Startability of Small Size DME Catalytic Combustor with Aid of Adsorption Heat
    Tameda Kazuma, Fujita Osamu, Procee[d]ings of Thermal Engineering Conference, 2007, 335, 336, 23 Nov. 2007
    This study investigates low temperature startability of dimethyl-ether (DME) catalytic combustor as a small size heat generator. A procedure of DME pre-supply followed by mixture supply into the reactor shows great improvement of startability. With this procedure catalyst surface temperature increases caused by DME adsorption heat at the period of DME pre-supply and increased temperature promote catalytic reaction. When the period of DME pre-supply is excess, the reactor temperature turns decrease by increased heat loss in comparison with adsorption heat. Consequently, it is suggested that the optimum condition for DME pre-supply exists to give best startability of DME catalytic combustor with this procedure., The Japan Society of Mechanical Engineers, Japanese
  • 104 Effect of pre-adsorbed species on the startability of DME catalytic combustor as a use of small size heat generator
    TAMEDA Kazuma, FUJII Toshio, FUJITA Osamu, 北海道支部講演会講演概要集, 2007, 46, 7, 8, 29 Sep. 2007
    The Japan Society of Mechanical Engineers, Japanese
  • 大学研究室めぐり、北海道大学機械宇宙工学専攻宇宙環境応用工学研究室
    藤田 修, 工業加熱, 44, 4, 62, 68, Jul. 2007, [Invited]
    日本工業炉協会, Japanese, Others
  • 微小重力環境を利用した固体燃焼現象研究:研究班WG報告—Solid combustion research in microgravity: Research WG report
    藤田, 修, 中村, 祐二, 永田, 晴紀, 菊池, 政雄, 伊藤, 昭彦, 梅村, 章, 高橋, 周平, Fujita, Osamu, Nakamura, Yuji, Nagata, Harunori, Kikuchi, Masao, Ito, Akihiko, Umemura, Akira, Takahashi, Shuhei, 宇宙利用シンポジウム 第23回 平成18年度 = Space Utilization Research: Proceedings of the Twenty-third Space Utilization Symposium, 137, 138, Mar. 2007
    Since solid combustion is dominated by diffusion process of pyrolyzed gas as well as heat balance around combustion area, which are strongly affected by convective flow, microgravity could be an effective tool to understand its mechanism. One of the most important contributions of solid combustion research in microgravity is fire safety in space. In the present report, some researches on going regarding fire safety in space will be introduced. Because individual physical processes included in the solid combustion have different time scale, it is specially noted that combination of short-term and long-term microgravity experiments is important to proceed the researches on solid combustion in space.
    資料番号: AA0063349036, 宇宙航空研究開発機構宇宙科学研究本部, Japanese
  • 短時間微小重力環境を利用した燃焼研究と宇宙実験への展開　　　　　　　　　　　　　　　
    藤田 修, 平成18年度宇宙環境利用の展望、（財）資源探査用観測システム・宇宙環境利用研究開発機構, 46, 58, Mar. 2007, [Invited]
    Japanese, Introduction commerce magazine
  • 微小重力環境を利用した火炎振動現象の研究－乱流火炎面に現れる不安定現象の解明を目指して－　　　　　　　　　　　　　　　
    藤田 修, 宇宙環境利用に関する公募地上研究ニュース, 8, 4, 5, Mar. 2007, [Invited]
    Japanese, Introduction commerce magazine
  • Flame oscillation phenomenon induced by external radiative heat supply
    Transaction of JSME, 73, 727, 803, 808, 2007
  • Soot formation characterisitcs of DME diffusion flame
    Transaction of JSME, 73, 727, 680, 686, 2007
  • B123 Characteristics of DME Catalytic Combustion as a Small Size Heat Source
    FUJII Toshio, FUJITA Osamu, Procee[d]ings of Thermal Engineering Conference, 2006, 49, 50, 23 Nov. 2006
    Dimethyl ether (DME) is used as a gaseous fuel which has many merits, and easy to transport and store. Catalytic combustion is a promising method to attain stable low temperature combustion. However, DME has less activity of catalytic combustion in comparison with hydrogen and methanol. Nonetheless, there is still few in a report of a study about the catalytic combustion of DME. The main objective in the present study is to investigate fundamental characteristics of DME catalytic combustion. The results showed that O_2 concentration of premixed gas affects the steady and transient behavior of DME catalytic combustion., The Japan Society of Mechanical Engineers, Japanese
  • 微小重力環境を利用した固体燃焼現象検討ＷＧ報告—WG report on Solid Combustion in Microgravity
    藤田, 修, 中村, 祐二, 永田, 晴紀, 菊池, 政雄, 伊藤, 昭彦, 岡島, 敏, 梅村, 章, 高橋, 周平, Fujita, Osamu, Nakamura, Yuji, Nagata, Harunori, Kikuchi, Masao, Ito, Akihiko, Okajima, Satoshi, Umemura, Akira, Takahashi, Shuhei, 宇宙利用シンポジウム = Space Utilization Research: Proceedings of Space Utilization Symposium, 22, Mar. 2006
    第22回宇宙利用シンポジウム(2006年1月17日-19日, 日本学術会議6階会議室 六本木、東京)
    The Twenty-second Space Utilization Symposium (January 17-19, 2006: Science Council of Japan, Roppongi, Tokyo, Japan)
    Since solid combustion, which has long time scale, is dominated by diffusion process of pyrolyzed gas, micorgravity could be an effective tool to understand its mechanism. One of the most important contributions of solid combustion research in microgravity is fire safety in space. In the present report, some researches attained previously as well as future expected subjects regarding fire safety in space will be introduced. Because individual physical processes included in the solid combustion have different time scale, combination of short-term and long-term microgravity experiments is requisite to proceed the research on solid combustion in microgravity.
    形態: カラー図版あり
    共催: 日本学術会議
    Physical characteristics: Original contains color illustrations
    Meeting sponsors: The Science Council of Japan, The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS)(JAXA)
    資料番号: AA0064113029, 宇宙航空研究開発機構宇宙科学研究本部, Japanese
  • DME ハンドブック　　　　　　　　　　　　　　　
    日本DMEフォーラム, 2006, [Invited]
  • Combustion Synthesis of Carbon Nanotubes under Microgravity Environment
    NAKADE Yusuke, UCHIYAMA Tomoyasu, ITO Hiroyuki, FUJITA Osamu, JASMA : Journal of the Japan Society of Microgravity Application = 日本マイクログラビティ応用学会誌, 22, 4, 320, 320, 28 Nov. 2005
    English
  • Effects of Gravity on Ignition of Polymer Insulated Wire induced by Excess Electric Current
    NODA Hiroya, FUJITA Osamu, NAKAMURA Yuji, JASMA : Journal of the Japan Society of Microgravity Application = 日本マイクログラビティ応用学会誌, 22, 4, 318, 318, 28 Nov. 2005
    English
  • 314 DME火炎におけるすす生成特性(熱工学(2))
    小林 雅律, 松村 智洋, 森岡 陽太郎, 藤田 修, 北海道支部講演会講演概要集, 2005, 44, 106, 107, 08 Oct. 2005
    一般社団法人日本機械学会, Japanese
  • 315 Catalytic Puriffication of NOx in DME Engine Exhaust Gas with Injection of Reducing Agent
    FUJII Toshio, FUJITA Osamu, 北海道支部講演会講演概要集, 2005, 44, 108, 109, 08 Oct. 2005
    The Japan Society of Mechanical Engineers, Japanese
  • Trend of Catalytic Combustion Research
    FUJITA Osamu, Journal of the Combustion Society of Japan, 46, 138, 233, 241, 30 Nov. 2004
    日本燃焼学会, Japanese
  • The Effect of Core Material on Combustion Behavior over Polyethylene Insulated Wire under Microgravity
    FUJITA Osamu, NISHIZAWA Katuhiro, KUDO Takuya, JASMA : Journal of the Japan Society of Microgravity Application = 日本マイクログラビティ応用学会誌, 21, 79, 79, 04 Nov. 2004
    English
  • Present and Future of Microgravity Combustion Research in Japan and USA
    FUJITA Osamu, JASMA : Journal of the Japan Society of Microgravity Application, 20, 4, 286, 291, 30 Oct. 2003
    Japanese
  • Description of planned microgravity facility and its use for combustion experiments
    FUJITA Osamu, KATO Taichi, ITO Kenichi, JASMA : Journal of the Japan Society of Microgravity Application, 20, 23, 23, 23 Oct. 2003
    English
  • Computational and Experimental studies of Thermophoretic Effect on Agglomeration of Soot Particles in Microgravity Diffusion Flame
    CHOI Jaehyuk, TSUIKI Takafumi, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2003, 43, 148, 149, 28 Sep. 2003
    The Japan Society of Mechanical Engineers, Japanese
  • Numerical Simulation of Flame Spread over Insulated Wire in Microgravity
    SATOH Hiroyuki, FUJITA Osamu, NISHIZAWA Katsuhiro, UMEMURA Akira, UCHIDA Masahiro, KIKUCHI Masao, 北海道支部講演会講演概要集, 2003, 43, 146, 147, 28 Sep. 2003
    The Japan Society of Mechanical Engineers, Japanese
  • Observation of a diffusion flame in a non-uniform magnetic field
    SUGAWARA Akifumi, FUJITA Osamu, 北海道支部講演会講演概要集, 2003, 43, 100, 101, 28 Sep. 2003
    The Japan Society of Mechanical Engineers, Japanese
  • Purification of DME Diesel engine exhaust gas by catalytic reactor
    TSUKUDA Masakazu, HATTORI Naoki, FUJITA Osamu, 北海道支部講演会講演概要集, 2003, 43, 120, 121, 28 Sep. 2003
    The Japan Society of Mechanical Engineers, Japanese
  • Effect of Radiation Absorption on the Flame Propagation in Tube
    IKEDA Junichi, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2003, 43, 158, 159, 28 Sep. 2003
    The Japan Society of Mechanical Engineers, Japanese
  • 512 張力を与えたPEEK^[○!R]膜材の宇宙環境曝露実験(高分子材料の劣化)(一般セッション)
    中村 孝, 中村 寛, 藤田 修, 野口 徹, 今川 吉郎, 学術講演会講演論文集, 52, 143, 144, 2003
    日本材料学会, Japanese
  • Atomic Oxygen Irradiation on PEEK Sheet under Tensile Loads
    NAKAMURA Hiroshi, NAKAMURA Takashi, NOGUCHU Toru, FUJITA Osamu, IMAGAWA Kichiro, TACHI Yoshiaki, 北海道支部講演会講演概要集, 2002, 42, 122, 123, 05 Oct. 2002
    The relationship between the polymeric material degradation by atomic oxygen (AO) and tensile load was investigated. AO irradiation experiments were carried out at the facility of National Space Development Agency (NASDA). AO was irradiated to PEEK sheets under tensile stress. After AO exposure, surface observation, reaction efficiency (Re) measurements, and tensile tests were made on the sample. As a result, the following were obtained : (1) The circular irradiated region can be observed on all exposed samples. (2) Re was increased by AO exposure under tensile stress. (3) Conical pits were observed allover on all exposed specimens. (4) Elastic modulus was decreased by AO irradiation and this tendency was enhanced by applied stress. It was clear that stress affected polymer degradation by AO., The Japan Society of Mechanical Engineers, Japanese
  • Distribution of intermediate formation and heat release in high temperature air combustion : Spatial distribution of CO
    JEON Byoungho, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2002, 42, 76, 77, 05 Oct. 2002
    Combustion could be sustained even in ultra low oxygen concentration by utilizing highly preheated air. In this research, methane combustion in high temperature air is examined to know the fundamental characteristics of high temperature combustion. Intensity of heat release distribution is estimated by analyzing spatial distribution of carbon monoxide, which is a main intermediate of methane combustion. The results showed that the broad distribution of heat release could be attained with high temperature and low oxygen content. Using this combustion method to the industrial furnace, it is anticipated that the homogeneous heating or heat controlling of the furnace., The Japan Society of Mechanical Engineers, Japanese
  • Electron Beam Irradiation on PEEK Sheets under Tensile Loads
    SAWAYA Masumi, NAKAMURA Takashi, NOGUCHI Toru, FUJITA Osamu, IMAGAWA Kichiro, TACHI Yoshiaki, 北海道支部講演会講演概要集, 2002, 42, 124, 125, 05 Oct. 2002
    A polymer, PEEK, was investigated how tensile load would effect on its characteristics when irradiated by electron beam (EB). PEEK sheets under different tensile stresses were irradiated to EB by using the Combined Space Effects Test Facility of NASDA. After EB radiati on, mass measurements, surface observation and tensile tests were made on the samples. As a result, the following were obtained : (1) No major changes were not observed in mass measurements. (2) Irradiated surface showed no difference from non-irradiated surface. (3) Decreases in tensile strength and elongation were detected for the sheets irradiated under tensile stress., The Japan Society of Mechanical Engineers, Japanese
  • Gasification of coal at high temperature and elevated pressure
    SHIMIZU Keisuke, FUJITA Osamu, ITO Kenichi, TAKAHASHI Jynya, 北海道支部講演会講演概要集, 2002, 42, 74, 75, 05 Oct. 2002
    Gasification of coal with CO_2 under high temperature and elevated pressure has been investigated in normal and microgravity. The results showed that the increase in CO_2 pressure increased the gasification reaction rate. Further, the reaction rate was affected by the gravitational condition, that is, higher reaction rate in microgravity than in normal gravity. It seemed that natural convection is so strong that coal gasification was suppressed under normal gravity. On the other hand gasification reaction proceeded under microgravity because enough reaction time was available with reduced external flow., The Japan Society of Mechanical Engineers, Japanese
  • Synthesis of Carbon Nanotubes in Microgravity Diffusion Flame
    FUJISAWA Kazuki, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2002, 42, 78, 79, 05 Oct. 2002
    Flame synthesis of carbon nanotubes has been attempted in microgravity diffusion flame. The experiments were carried out with different fuel in various oxgen concentrations. Carbon nanotubes were collected from the diffusion flame for subsequent transmission electron microscopy (TEM) analysis by TEM grid. Finally some multi-walled carbon nanotubes with a diameter in the range of 5-20nm were found to grow on a Fe particle in diffusion flames. It was suggested that Fe particles acted as catalyst and flame synthesis could be a large-scale production method of carbon nanotubes., The Japan Society of Mechanical Engineers, Japanese
  • Observation of heavy droplet combustion in microgravity
    SUDO Makoto, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2002, 42, 72, 73, 05 Oct. 2002
    Combustion of heavy fuel droplet in microgravity was studied. The tested fuels were n-nonadecane and LCO. The external air flow velocity in the combustion chamber was 4.7cm/s. Laser extinction method has been used to measure droplet diameter and to visualize the soot distribution in the flame. Results showed that burning rate and soot volume increased with O_2concentration in the test of n-nonadecane. LCO combustion produced more soot than n-nonadecane and had lower burning rate than n-nonadecane in the same condition., The Japan Society of Mechanical Engineers, Japanese
  • Experience of Application to The First IAO for Microgravity Science
    FUJITA Osamu, JASMA, 19, 3, 167, 170, 31 Jul. 2002
    日本マイクログラビティ応用学会, Japanese
  • Research on Solid Material Ignition with Laser Irradiation in Microgravity
    ITO Kenichi, FUJITA Osamu, TAKAHASHI Junya, JASMA : Journal of the Japan Society of Microgravity Application, 18, 20, 20, 01 Oct. 2001
    English
  • 619 The Effect of Gas-Phase Radiation Absorption on Flame Propagation Phenomenon
    MORI Takemi, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2001, 41, 126, 127, 25 Sep. 2001
    Gas-phase absorption of radiation was experimentally investigated. CO_2 laser beam (λ=10.6μm) was penetrated through a longitudinal combustion chamber (vacuum or filled with air or CO_2 gas), and then the laser absorption and temperature change in the vessel were measured It was found that CO_2 gas can absorb the radiation to increase the temperature. Furthermore, flame propagation experiment was carried out. CH_4/O_2/CO_2 premixed flame with external radiation was observed., The Japan Society of Mechanical Engineers, Japanese
  • 708 Experimental Study on Radiative Ignition of Filter Paper with Visible Light under Microgravity
    Takahashi Junya, Sugawara Akifumi, Fujita Osamu, Ito Kenichi, 北海道支部講演会講演概要集, 2001, 41, 240, 241, 25 Sep. 2001
    An experiment on radiative ignition of solid fuel has been performed in microgravity to determine the events occurring in the ignition processes in a quiescent field. Filter paper was irradiated by Diode laser (800.1nm) in various oxygen concentrations (0-50%). Using the Diode laser makes it possible to observe the radiative ignition without the effect of gas phase absorption. The ignition delay was measured for various experimental conditions. The density change of gas phase before ignition were observed by a Mach-Zehnder interferometer. The results showed that heat conduction from the sample surface induced weak chemical reaction in the vicinity of the sample surface, which propagated outward to reach strong combustion. Ignition delay time decreased with increase in O_2 concentration because mixture near the sample surface might contain more oxygen with higher oxygen atmosphere to cause immediate transition from the weak chemical reaction to the strong combustion., The Japan Society of Mechanical Engineers, Japanese
  • 627 The Formation of N_2O in the Catalytic Purification of the DME Combustion Exhaust Gas
    OHMURA Hideaki, FUJISAWA Kazuki, FUJITA Osamu, ITO Kenichi, 北海道支部講演会講演概要集, 2001, 41, 142, 143, 25 Sep. 2001
    The formation of N_2O in the catalytic purification of simulated DME engine exhaust gas is investigated. Main parameters are catalytic reactor temperature and NO inlet concentration. The results show that there is a possibility of the considerable N_2O formation in the process of catalytic NO reduction. The amount of N_2O formation changes with NO concentration in the simulated exhaust gas, and then shows the maximum value as a function of catalyst temperature. Therefore, N_2O formation characteristic during NOx reduction is very important factor in the performance evaluation of the NOx catalyst for DME engine exhaust gas., The Japan Society of Mechanical Engineers, Japanese
  • 706 Combustion Behavior of Paper Sheet in a Low External Flow under Microgravity : Discussion based on Temperature Measurement
    NISHIZAWA Katsuhiro, FUJITA Osamu, ITO Kenichi, OLSON Sandra L., KASHIWAGI Takashi, 北海道支部講演会講演概要集, 2001, 41, 236, 237, 25 Sep. 2001
    Flame spreading over thin paper in low external air flow has been performed in microgravity. Two ignition methods, kanthal wire heater and CO_2 laser, were examined. The flame spread rates were measured under various oxygen concentrations and external flow velocity. The result showed that external flow velocity had a strong effect on flame spread rates. Temperature distributions indicated that pyrolysis temperature increased and the preheating length decreased with increasing air flow velocity. There are no particular differences in surface temperature distribution between 2D and 3D flames., The Japan Society of Mechanical Engineers, Japanese
  • 629 Flame Stability of Premixed Type Kerosene Foam Burner
    TAKADA Masaru, WATANABE Daisuke, FUJITA Osamu, YAMANE Kiyotaka, ITO Kenichi, ANZAWA Norio, 北海道支部講演会講演概要集, 2001, 41, 146, 147, 25 Sep. 2001
    This paper represents the research of a premixed type kerosene foam burner. This burner can attain a low excess air ratio premixed combustion even with liquid fuel. Experiments were carried out with changing the combustion load and the excess air ratio. This burner can realize the stable premixed combustion in given conditions with respect to combustion load and excess air ratio. To consider about the flame stability in the burner, the numerical simulation using the heat circulation model was attempted. The result shows that the flame stability of the burner depends on the heat circulation, especially the feedback heat from flame to the porous plate., The Japan Society of Mechanical Engineers, Japanese
  • Importance of Ground-Based Microgravity Experiments with Drop Shafts for Combustion Research
    FUJITA Osamu, JASMA, 18, 3, 156, 161, 31 Jul. 2001
    日本マイクログラビティ応用学会, Japanese
  • 微小重力場における拡散火炎中のすす粒子凝集挙動
    伊藤 献一, 藤田 修, 燃焼研究, 125, 21, 31, 18 Jul. 2001
    日本燃焼学会事務局, Japanese
  • 303 Observation of Flame Spread Over Wire Insulation in Slow External Flow under Microgravity
    NISHIZAWA Katsuhiro, FUJITA Osamu, ITO Kenichi, TAKESHITA Yasuhiro, 東海支部地区講演会講演論文集, 2001, 72, 73, 2001
    日本機械学会東海支部, Japanese
  • Observation of Spherical Fuel Combustion within a Low External Flow under Microgravity
    FUJITA Osamu, INOUE Yoriaki, ITO Kenichi, TAKESHITA Yasuhiro, JASMA : Journal of the Japan Society of Microgravity Application, 17, 7, 8, 01 Oct. 2000
    English
  • 518 Effect of External Flow Velocity on Flame Spread over Wire Insulation in Microgravity
    NISHIZAWA Katsuhiro, FUJITA Osamu, ITO Kenichi, KIKUCHI Masao, OLSON Sandra L., TAKESHITA Yasuhiro, 北海道支部講演会講演概要集, 2000, 40, 216, 217, 25 Sep. 2000
    Microgravity combustion experiments were conducted to acquire data on the effect of external flow velocity on combustion phenomena of solid material. Polyethylene insulated wire were used as a test sample. The flame spread rates were measured under various oxygen concentrations, external flow velocity and dilution gases. The result showed that external flow velocity had a weak effect for flame spread rates with polyethylene sample under all O_2 concentrations., The Japan Society of Mechanical Engineers, Japanese
  • 505 Combustion of high boiling point fuel in a low external air flow
    INOUE Yoriaki, FUJITA Osamu, ITO Kenichi, TAKESHITA Yasuhiro, 北海道支部講演会講演概要集, 2000, 40, 190, 191, 25 Sep. 2000
    Combustion of high boiling point fuel in a slow air flow was investigated under microgravity. Air flow velocity was varied from 4.1cm/sec to 15.8cm/sec, then flame shape varied from spherical to spindle shape. Density of soot formed in a flame decreased with an increase of relative velocity. According to the laser shadow image, down wind soot distribution with slow external flow showed a maximum density at a certain distance from the sample and then, rapidly decreased around rear edge of the flame., The Japan Society of Mechanical Engineers, Japanese
  • 504 Observation of soot formation in a laminar diffusion flame sustained above a flat plate under microgravity
    TAKAMOTO Yoshiteru, FUJITA Osamu, ITO Kenichi, SAKURAYA Takashi, 北海道支部講演会講演概要集, 2000, 40, 188, 189, 25 Sep. 2000
    Soot formation in a boundary layer type laminar diffusion flame sustained above a flat plate under microgravity is studied. The main parameters are gas temperature, oxygen mass fraction, and gas flow velocity. The effects of these parameters on the position and strength of soot formation are observed with optical method. The results showed that higher temperature and O_2 concentration increased the soot formation. The flow velocity strongly affected the position of soot formation., The Japan Society of Mechanical Engineers, Japanese
  • Combustion Characteristics of Propellants for End-burning Hybrid Rockets
    NAGATA Harunori, HASHIMOTO Nozomu, KATO Takahiro, FUJITA Osamu, ITO Kenichi, KUDO Isao, AKIBA Ryojiro, JASMA, 17, 3, 172, 177, 31 Jul. 2000
    日本マイクログラビティ応用学会, Japanese
  • B112 Mechanism of Flame Spreading over Polystyrene Bead Array in Microgravity(Solid combustion/incinerator) :
    Fujita Osamu, Ito Kenichi, Takahashi Junya, Proceedings of the ... JSME-KSME Thermal Engineering Conference, 1, "1, 163"-"1-168", 2000
    Flame spreading over polystyrene beads arranged in line have been investigated under microgravity as a simulation of flame propagation phenomena of particle cloud combustion. Some experimental parameters, such as O_2 concentration, particle spacing, pressure, and inert gas type, have been examined to know their effect on the flame spreading characteristics. Further, the temperature distribution ahead of the propagating flame front have been estimated by the Mach-Zehnder interferometry. Based on these results the mechanism of flame spreading over fuel particle array has been discussed. The results showed that the importance of relative position between flame front and unburned fuel particle next to the flame front. When the particle is farther than the flame radius, thermal diffusion process has a strong effect on the flame spread rate, while its effect is not so dominant when the flame radius is larger than the particle spacing. The importance of the radiation reabsoption phenomena was also pointed out based on the interferometry results., 日本機械学会, English
  • B110 EFFECTS OF COAL PARTICLES SEEDING ON BURNING VELOCITY OF METHANE-AIR MIXTURES(Droplet/particle combustion-2) :
    NAGATA Harunori, FUJITA Osamu, ITO Kenichi, KUDO Isao, TAKESHITA Yasuhiro, Proceedings of the ... JSME-KSME Thermal Engineering Conference, 1, "1, 151"-"1-155", 2000
    This paper describes experimental and numerical studies about effects of coal particles seeding on flame propagation velocity and burning velocity of lean methane-air mixtures. To produce uniform coal dust clouds and to eliminate the buoyancy effect, experiments are carried out under microgravity environment, being obtained with the 500-m drop shaft of Japan Microgravity Center (JAMIC). Experimental and numerical results reveal that seeding of an appropriate amount of coal particles increases flame propagation velocity. In spite of this, the increase of burning velocity is almost zero or very small. Accordingly, the main cause of the enhancement of flame propagation velocity is the gas expansion due to coal combustion behind the methane-air flame. This is because coal combustion is nearly isolated from methane combustion in conditions investigated in this study., 日本機械学会, English
  • Observation of Flame Spread Phenomena Over Wire Insulation Material in Microgravity-Effect of Surrounding Gas component and Sample Geometry-
    FUJITA Osamu, KIKUCHI Masao, ITO Kenichi, JASMA : Journal of the Japan Society of Microgravity Application, 16, 63, 64, 01 Oct. 1999
    English
  • Removal of Unburned Species in Simulated Methanol Engine Exhaust Gas with NO_x Purification Catalyst
    FUJITA Osamu, ALAM Mahabubul, ITO Kenichi, Transactions of the Japan Society of Mechanical Engineers. Series B., 65, 634, 2165, 2171, 25 Jun. 1999
    Characteristics of methanol reduction and formaldehyde formation with NO_x purification catalyst (NO_x catalyst) have been investigated to know the applicability of NO_x catalyst to lean burn or diesel type methanol engine. The catalysts used in this research were Co-γAl_2O_3 and Sn-Al_2O_3 as examples of NO_x catalysts and Pt-Al_2O_3 as an oxidation catalyst to be compared with NO_x catalyst. Pure γAl_2O_3 was also used additionally. Laboratory experiments were conducted by using above catalysts in oxygen rich atmosphere considering lean burn methanol engines or diesel type methanol engines. Reaction temperature and presenting NO concentration were selected as experimental parameters. The experimental results showed that methanol reduction temperature with NO_x catalyst became around 150℃ higher than that with oxidation catalyst and it became closer to engine exhaust gas temperature level. Large amount of formaldehyde was formed during the use of NO_x catalyst at a certain temperature range. The formation temperature range is higher than that with Pt catalyst, which may cause higher formaldehyde formation in the engine exhaust gas. Effect of NO on methanol oxidation and formaldehyde formation characteristics with NO_x catalyst was significant as was observed in oxidation catalysts. With increase in NO, methanol reduction rate became lower and the amount of formaldehyde formation increased., The Japan Society of Mechanical Engineers, Japanese
  • Combustion Behavior of Polyethylene Insulated Wires under Microgravity
    KIKUCHI Masao, FUIJTA Osamu, ITO Kenichi, SAKURAYA Takashi, JASMA, 16, 2, 119, 128, 20 May 1999
    日本マイクログラビティ応用学会, Japanese
  • Flame Spread over Wire Insulation under Microgravity
    FUJITA Osamu, KIKUCHI Masao, ITO Kenichi, SATO Atsuki, SAKURAYA Takashi, Transactions of the Japan Society of Mechanical Engineers. Series B., 65, 632, 1473, 1478, 25 Apr. 1999
    An experimental study of flame spread phenomena over ETFE (Ethylene-Tetrafluoroethylene) insulated wire was performed under microgravity to obtain fundamental data on fire safety in space. The effects of the parameters thought dominant for wire combustion in fires-the ambient oxygen concentration, wire initial temperature, T_i, and wire diameter, d_ω,- were investigated in the microgravity experiments. A series of comparative experiments were also conducted at normal gravity. Flame shape under microgravity changed depending on the state of the molten fuel accumulation. Experimental results showed that there existed a possibility of higher flame spread rates under microgravity than at normal gravity, in spite of lower flame temperature in microgravity. Wire initial temperature, T_i, had a very large influence both on flame spread rates and extinction limit of the wire under microgravity. The degree of flame spread rate decreased with increase in d_ω and, correspondingly, the increase with decrease in d_ω under microgravity was higher than at normal gravity., The Japan Society of Mechanical Engineers, Japanese
  • On the Colors of Laminar Flames
    Tatsuta Setsuo, Fujita Osamu, Ito Kenichi, 旭川工業高等専門学校研究報文, 36, 11, 19, 1999
    Asahikawa National College of Technology, English
  • Determination of soot volume fraction in microgravity diffusion flames based on soot visualization technique
    HAMADA Makoto, FUJITA Osamu, ITO Kenichi, SAKURAYA Takashi, JASMA : Journal of the Japan Society of Microgravity Application, 15, 65, 66, 01 Oct. 1998
    English
  • Soot Agglomeration in a Boundary-layer Type Diffusion Flame under Microgravity
    IGUCHI Akinori, FUJITA Osamu, ITO Ken'ichi, TAKESHITA Yasuhiro, JASMA : Journal of the Japan Society of Microgravity Application, 15, 67, 68, 01 Oct. 1998
    English
  • Visualization and size measurement of soot agglomerates in microgravity diffusion flames
    ITO Kenichi, FUJITA Osamu, TAKEUCHI Atsushi, HAMADA Makoto, SAKURAYA Takashi, JASMA : Journal of the Japan Society of Microgravity Application, 14, 45, 46, 01 Oct. 1997
    English
  • Kashiwagi, T., Mell, W. E, McGrattan, T., Baum, H. R., Olson, S. L., Fujita, O., Kikuchi, M. and Ito, K. : "Ignition, Transition, Proc. Flame Spread in Multidimensional Configurations in Microgravity", NASA Conference Publication 10194(Proceeding of Th・・・　　　　　　　　　　　　　　　
    1997
    Kashiwagi, T., Mell, W. E, McGrattan, T., Baum, H. R., Olson, S. L., Fujita, O., Kikuchi, M. and Ito, K. : "Ignition, Transition, Proc. Flame Spread in Multidimensional Configurations in Microgravity", NASA Conference Publication 10194(Proceeding of The Fourth International Microgravity Combustion Workshop), 441-416 (1997)
  • Use of Microgravity Environment to Investigate the Effect of Magnetic Field on Flame Shape　　　　　　　　　　　　　　　
    O. Fujita, Y. Kuroda, K. Ito, N. I. Wakayama, Y. Takeshita, Proceedings of the 20th International Symposium on Space Technology and Science, 946, 951, 1996
    English, Summary international conference
  • Measurement of Flame Propagation Rate in a Pulverized Coal Cloud
    MASUKO Katsumi, SATO Jun'ichi, KITANO Kunihiro, ITO Ken'ichi, FUJITA Osamu, SAKAMOTO Hiroaki, JASMA : Journal of the Japan Society of Microgravity Application, 12, 4, 319, 320, 31 Oct. 1995
    English
  • A study on flame propagation of polystyrene foam beads under microgravity for simulation of particle cloud combustion
    FUJITA Osamu, ITO Kenichi, NAKAMURA Keiichi, JASMA : Journal of the Japan Society of Microgravity Application, 12, 4, 323, 324, 31 Oct. 1995
    English
  • OBSERVATION OF MICROGRAVITY DIFFUSION FLAMES WITHIN A MAGNETIC FIELD
    FUJITA Osamu, KURODA Yukio, ITO Kenichi, WAKAYAMA Nobuko I., TAKESHITA Yasuhiro, The Journal of space technology and science : a publication of Japanese Rocket Society, 11, 2, 18, 27, 01 Sep. 1995
    English
  • Characteristics of Catalytic Combustion Using Butane Premixed Gas
    Kudo Hitoshi, Fujita Osamu, Ito Kenichi, Research reports, Kushiro Technical College, 26, 23, 32, 18 Dec. 1992
    Kushiro National College of Technology, Japanese
  • Characteristics of Catalytic Combustion Using Butane Premixed Gas (Effect of Operating Conditions on Steady-State Characteristics)
    Kudoh Hitoshi, Fujita Osamu, Ito Ken'ichi, Research reports, Kushiro Technical College, 25, 33, 41, 20 Dec. 1991
    Kushiro National College of Technology, Japanese
  • Characteristics of Catalytic Combustion Using Butane Premixed Gas
    伊藤 献一, 藤田 修, 工藤 均, Bulletin of the Faculty of Engineering,Hokkaido University, 155, p41, 49, May 1991
    北海道大学 = Hokkaido University, Japanese
  • Catalytic Combustion of Lean Methanol Mixture
    伊藤 献一, 藤田 修, 岩井 保憲, 崔 炳喆, 山根 清隆, Bulletin of the Faculty of Engineering,Hokkaido University, 140, p73, 81, May 1988
    北海道大学 = Hokkaido University, Japanese
  • Effect of conductor on spreading flames over wire in microgravity
    Shuhei Takahashi, Hiroyuki Ito, Yuji Nakamura, Osamu Fujita, 43rd International Conference on Environmental Systems
    Tests with flames spreading over wires in microgravity were performed with applying power to the inner core wire to examine the influence of inner core heating on the flame spread rate and extinction limit. In the experiments, low density polyethylene insulated Nickel-chrome wire was used as a sample. The experiments were conducted both in normal gravity and microgravity attained by parabolic flights in external opposed flow conditions from 50 to 250 mm/s. The experimental results indicated that flame spread rate becomes about 1.5 times faster with applying 12.4 W/m to the inner core than without applying power. One of the reasons of this result is the decrease of required heat for pyrolysis due to the preheated insulation. Further, increase of heat input from flame to the insulation also might have enhanced flame spread. The flammability tests in 1g indicated that the limiting value of the oxygen concentration decreased with the increase of applying power to the inner core: flame became more flammable by applying power to the inner core. Further, the limiting value of the oxygen concentration decreased in μg at every applying power condition at 150 mm/s flow velocity condition. T

Books and other publications

Lectures, oral presentations, etc.

  • Fundamental research on solid material combustion utilizing long-term microgravity environment provided by ISS/KIBO　　　　　　　　　　　　　　　
    Osamu Fujita
    15th Asia-Pacific Conference on Combustion (ASPACC 2025), 19 May 2025, English, Keynote oral presentation
    [Invited]
  • Role of Microgravity Utilization in Combustion Research　　　　　　　　　　　　　　　
    Osamu Fujita
    14th Asian Microgravity Symposium, 02 Dec. 2024, English, Invited oral presentation
    01 Dec. 2024 - 06 Dec. 2024, [Invited]
  • Research on Solid Material Flammability in Microgravity for Fire Safety in Space (Fluid Science Research Award Lecture)　　　　　　　　　　　　　　　
    Osamu Fujita
    ICFD (International Conference on Flow Dynamics), 19 Nov. 2024, English, Invited oral presentation
    19 Nov. 2024 - 21 Nov. 2024, [Invited]
  • Use of Microgravity for Understanding Combustion Phenomena (Plenary lecture)
    Osamu Fujita
    The 61st Symposium (Japanese) on Combustion, 15 Nov. 2023, Combustion Society of Japan, Japanese, Invited oral presentation
    15 Nov. 2023 - 17 Nov. 2023, Akita city, Japan, [Invited], [Domestic Conference]
  • Introduction of Combustion Research Project "FLARE" utilizing ISS/KIBO for Fire Safety Standard in the Next Generation　　　　　　　　　　　　　　　
    Osamu Fujita
    6th International Symposium on Physical Science in space, 16 Sep. 2015, English, Keynote oral presentation
    [Invited], [International presentation]
  • INTERACTION BETWEEN ACOUSTIC VIBRATION AND PROPAGATING FLAMES DEFORMED BY EXTERNAL LASER IRRADIATION IN A COMBUSTION TUBE　　　　　　　　　　　　　　　
    Osamu Fujita, Yoshikazu Taniyama
    The 5th East Asia Mechanical and Aerospace Engineering Workshop, 28 May 2015, English, Keynote oral presentation
    [Invited], [International presentation]
  • Impact of Gravity on Wire Insulation Combustion　　　　　　　　　　　　　　　
    FUJITA Osamu
    Asian Microgravity Symposium 2014, 30 Oct. 2014, English, Keynote oral presentation
    [Invited], [International presentation]
  • Solid Combustion Research in Microgravity as a Base of Fire Safety in Space
    FUJITA Osamu
    35th International Symposium on Combustion, 06 Aug. 2014, English, Invited oral presentation
    [Invited], [International presentation]
  • Impact of Gravitational Field on Flammability of Solid Material　　　　　　　　　　　　　　　
    FUJITA Osamu
    8th Asia-Pacific Conference on Combustion, 12 Dec. 2010, English, Invited oral presentation
    [Invited], [International presentation]

Affiliated academic society

  • Mar. 2025
    The Gas Turbine Society of Japan　　　　　　　　　　　　　　　
  • Mar. 2025
    Society of Automotive Engineers of Japan　　　　　　　　　　　　　　　
  • The Combustion Institute　　　　　　　　　　　　　　　
  • Japan Association for Fire Science and Engineering　　　　　　　　　　　　　　　
  • Japan Soceity of Microgravity Application　　　　　　　　　　　　　　　
  • The Japan Society for Aeronautical and Space Sciences (JSASS)　　　　　　　　　　　　　　　
  • Combustion Society of Japan (Japan Section of the Combustion Institute)　　　　　　　　　　　　　　　
  • The Japan Society for Mechanical Engineers　　　　　　　　　　　　　　　

Works

  • 50m級微小重力実験設備の設置　　　　　　　　　　　　　　　
    2006
  • Construction of New 50m dorp tower for microgravity experiments　　　　　　　　　　　　　　　
    2006
  • 外部から見たNASDAの先端実験設備の利用に対する期待（招請講演）　　　　　　　　　　　　　　　

Research Themes

  • 月面基地等の低重力環境下における固体材料火災安全性評価手法の開発
    科学研究費助成事業
    28 Jun. 2024 - 31 Mar. 2026
    橋本 望, 藤田 修, 金野 佑亮
    日本学術振興会, 挑戦的研究(萌芽), 北海道大学, 24K21649
  • Quantitative estimation of onset condition for combustion insatiability of NH3 premixed flame in a combustion tube
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Apr. 2022 - Mar. 2025
    Osamu Fujita, Nozomu Hashimoto
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 22H01408
  • Combustion and flame spread physics over multi-layer flammable material in microgravity
    Grants-in-Aid for Scientific Research
    08 Mar. 2023 - 31 Mar. 2024
    藤田 修, WANG QIANG
    実験で使用される複合材料として回路基板でしばしば使用されるフェノール樹脂と銅箔を結合させたもの、解析の容易さを考慮してPMMAと銅箔を貼り合わせたもの、そして、電線の被覆材の三種類を選定した。また、PMMAに関しては比較実験として銅箔のないものについて実験を行った。フェノール樹脂とPMMAについては燃え拡がり現象の観察、電線に関しては短絡が生じた場合の着火現象を対象として研究を行った。
    複合材料の燃え広がり実験については、昨年度確立した実験手法を活用し、試料の厚さおよび幅の影響、試料と周囲壁の間隔の影響、周囲流速影響、酸素濃度影響など、実験の変数を増やし、系統的なデータ取得を行った。さらに、複合材料上を燃え拡がる火炎に現れる非定常燃え拡がり現象についても実験的観察を行い多くの実験結果を得た。例えば、燃え拡がり速度は、一般に試料厚みに反比例するが、複合材料ではその関係性は成り立たず、新たな理論モデル構築が必要となることがわかった。微小重力場では形成される火炎に対する重力影響が本質的な影響を持つことから、噴流火炎に対する重力影響を調べるため、燃料噴流の重力方向に対する角度の違いによる火炎の安定限界の変化についても系統的に取得することに成功した。
    複合材料の微小重力場における着火実験については、新たな実験装置を製作したうえで、北海道赤平市にある50m級落下塔を使用した実験に成功した。その結果、着火限界条件は微小重力場の方が通常重力場に比べ拡大するものの、周囲空間のサイズによりその限界条件が大きく変化することがわかった。また、並行して数値解析を進め、計算による着火遅れ時間が実験で得られた傾向を再現できることを確認した。
    これらの研究で得られた成果は、国際学術誌(Combustion and Flame)や講演会（航空宇宙学会、日本燃焼学会、等)で公表した。
    Japan Society for the Promotion of Science, Grant-in-Aid for JSPS Fellows, Hokkaido University, 22KF0008
  • 微小重力場における可燃性複合材料の燃焼と燃え拡がりの物理
    科学研究費助成事業
    18 Nov. 2021 - 31 Mar. 2024
    藤田 修, WANG QIANG
    日本学術振興会, 特別研究員奨励費, 北海道大学, 21F21343
  • Fire physics of spreading flame over multi-layer flammable material in microgravity
    Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows
    Jul. 2022 - Mar. 2024
    Osamu Fujita, Wang Qiang
    Japan Society for the Promotion of Science, Grant-in-Aid for JSPS Fellows, Hokkaido University, 22F21343
  • Study on coupling mechanism of acoustic vibration and propagating premixed flame by using laser irradiation method
    KAKENHI KIBAN (A)
    Apr. 2018 - Mar. 2023
    FUJITA Osamu
    本年度は、再生可能エネルギー由来の燃料として期待されるNH3に重点を置いた研究を進め、以下の３つの項目について成果を得た。
    (1)管内伝播火炎の燃焼振動発生におよぼす代替燃料の混入割合の影響：再生可能エネルギー由来の燃料として期待されるNH3を選択し、その代替率と不安定性が発現する限界条件の関係を実験的に取得した。この結果、混合燃料（NH3とCH4の混合）中のNH3比率に対する不安定性の変化を特定の当量比について取得し、NH3の混合割合が増加すると燃焼振動の発生限界が拡大することを示した。また、この結果について考察を行い、NH3による燃料代替率が上昇するとルイス数が低下することが大きな影響を与えている可能性を指摘した。また、NH3を混入すると伝播管内で不安定性の増幅する火炎位置が変化するという結果が得られており、Pressure Couplingの不安定性への寄与を考慮する必要性を示した。
    (2)平面火炎の圧力変動に対する不安定現象発現時の火炎構造の観察：従来から炭化水素燃料を対象として行ってきた、平面火炎に現れるParametric Instability発生時の詳細構造をNH3火炎を対象として観察し、炭化水素を燃料とした場合と比較を行った。この結果、火炎面に現れるセル構造の波数や発光強度の時間変化は両者で異なり、反応過程で生じる中間生成物（H2や活性化学種）を含めた拡散係数を考慮した不安定性の議論が必要であることを示した。
    (3)変形を与えた火炎の不安定性の観察：これまでの研究で確立してきたレーザ照射法により、変形させた火炎の圧力変動の増幅率や不安定性の発生限界をNH3/C2H4混合燃料に対して調べた。この結果、火炎変形はNH3混合燃料の場合でも圧力増幅率を増加させ、Velocity couplingは依然として燃焼振動を発生させる重要な機構の一つであることが示された。また、純粋な炭化水素燃料と比較すると(1)でも述べたとおりNH3の混入が不安定性を増加させるという結果が得られた。
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, Principal investigator, Competitive research funding, 18H03755
  • Clarification and model development for the interaction mechanism of solid fuels and gaseous fuels during the mixing-combustion
    Grants-in-Aid for Scientific Research
    01 Apr. 2019 - 31 Mar. 2022
    Hashimoto Nozomu
    In this study, the detailed flame structure and the interaction between the gaseous fuel and the solid particle cloud for the co-combustion field of the gaseous fuel and the solid particle cloud were clarified. For the co-combustion of gaseous fuel / solid particle cloud, it was clarified that there are two interaction effects, namely, (1) the heat absorption effect of solid particles, and (2) the equivalence ratio increase effect by the evolution of volatile matter from solid particles, in the pre-heat zone of the flame. The outcome of this study is expected to contribute for the introduction of carbon-free energy carrier gas and operation of various high temperature processes using solid fuel.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 19H02073
  • レーザ加熱火炎面曲率制御法によるＧＴ燃焼器の不安定振動燃焼トリガー機構の研究　　　　　　　　　　　　　　　
    科学研究費補助金基盤研究（Ｂ）
    Mar. 2014 - Mar. 2018
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • Modeling
    Grants-in-Aid for Scientific Research
    01 Apr. 2015 - 31 Mar. 2017
    Hashimoto Nozomu, WATANABE Hiroaki, KUROSE Ryoichi, FUJITA Osamu, TAKAHASHI Hiroyasu
    A model that can reproduce the phenomena of soot formation from the volatile matter evolved from solid particles for the unsteady numerical simulation of solid combustion field has been developed. 13 species including tar are postulated as volatile matter. The model can take into account the effect of particle heating rate on the amount of volatile matter and its evolution rate. The large eddy simulation of the 4 kW coal combustion filed with the developed model was conducted. As a result, the tendency of the soot volume fraction distribution predicted by the numerical simulation was consistent with that obtained by the optical measurement. The high accuracy of the developed model was validated by the comparison.
    Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), Hokkaido University, 15K17992
  • Development of new combustion method of densified solid biomass fuel
    Grants-in-Aid for Scientific Research
    01 Apr. 2014 - 31 Mar. 2017
    Ito Hiroyuki, FUJITA OSAMU
    A possibility of the new combustion method in which combustion region is formed at one end of a columnar briquette and propagates one dimensionally was investigated. As a result of the combustion experiments in the case with cylindrical briquette, it was confirmed that there is a condition in which the mass loss rate is almost constant. In the condition, it was observed that the flames are formed around the outer periphery at the lower part of the briquette and above the top end, and the long char combustion region was formed above the flame formed around the briquette. In the case of 1100 and 1300 kg/m3 briquette density, both the mass loss rate and the combustion efficiency decreased with high and low air flow rate and, therefore, they have a peak at moderate air flow rate.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Kanagawa University, 26420160
  • Soot generation map for Oxy-Fuel combustion and its extenstion method　　　　　　　　　　　　　　　
    Grant-in-Aid for Scientific Research
    Apr. 2015 - Mar. 2017
    FUJITA Osamu
    Japan Society for the Promotion of Science, Principal investigator, Competitive research funding
  • 固体材料の微小重力場における着火・消炎およびすす生成挙動に関する研究
    科学研究費助成事業
    01 Apr. 2012 - 31 Mar. 2015
    藤田 修, HU Longhua
    本研究においては、研究計画に沿って、以下の２項目について実施した。
    1. 固体材料表面を燃え広がる火炎の燃え広がり速度におよぼす試料傾きの影響
    実験用試料として、ポリエチレン被覆の電線を選定し、この燃え広がり速度に及ぼす角度の影響（水平からの傾きの角度：-90度～+90度）を調べた。電線の心線材質としては通常の銅の他にニクロム心線を用いた。また、実験変数として雰囲気圧力を変化させた。この結果、電線上火炎燃え広がり速度は、銅心線の場合角度が0度（水平）の場合が最も燃え広がり速度が小さくなり、角度が正、負のいずれに傾いても（すなわち、自然対流が同軸流、対向流のいずれも場合でも）燃え広がり速度は増大することがわかった。一方、心線がニクロムとなった場合は、試料の傾きが正の角度（対向流）が負の角度（同軸流）へ変化すると燃え広がり速度は単調減少することがわかった。これらのことが生じる要因を、新たに構築した熱循環モデルに基づき検討し、実験結果を良く再現できることを明らかにした。これらの結果は、Proc.Combustion Instituteにて公表されている。
    ２．燃え広がり火炎の消炎限界に対する試料傾きの影響
    上記の実験に引き続いて、電線上燃え広がり火炎の消炎限界酸素濃度（LOC)に対する試料傾きの影響を調べた。この結果静止雰囲気においては、LOCは、試料が水平の時最も大きな値を示しそれよりいずれの方向に傾いても低下するという興味深い結果が得られた。さらに、周囲に流動を与えた場合は、試料周囲に生じる自然対流の電線に沿う速度成分と対向周囲流速がちょうど釣り合うような条件の時に、LOCが極大になることを実験的に初めて示した。この結果は、Asian Microgravity SymposiumのKey Note Speechとして発表している。


    日本学術振興会, 特別研究員奨励費, 北海道大学, 12F02360
  • レーザ加熱法を用いた火炎面曲率制御によるFlame Dynamicsの研究　　　　　　　　　　　　　　　
    科学研究費補助金基盤研究（Ｂ）
    Apr. 2009 - Mar. 2013
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • Study on seslective synthesis of alternative chemical materials originated from biomass by using non-equilibrium plasma
    Grants-in-Aid for Scientific Research
    2011 - 2013
    ITO HIROYUKI, FUJITA Osamu
    By heating solid biomass such as wood and waste, liquid fuel and chemical materials, alternative of the fossil fuel, can be obtained because it generates liquid tar via pyrolysis reaction. However, it is difficult to control the composition of liquid tar by giving only heat so far. In this study, gas is dissociated electrolytically to the electrons which has high energy and ions (called non-equilibrium plasma) by adding the energy. The objective of the study is to confirm whether non-equilibrium plasma can change the product yield and composition or not.
    Cellulose, one of major components of wood, was used as a biomass material. The change in gas and liquid tar composition was researched by applying argon or hydrogen plasma. The promotion of cellulose pyrolysis in lower temperature region was suggested with argon plasma.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), 23603001
  • バイオ原料由来高密度固体燃料の定常端面燃焼の研究
    科学研究費補助金 挑戦的萌芽研究
    Apr. 2010 - Mar. 2012
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • Elucidation of the enhancement mechanism of carbon nanotube growth by combustion plasma
    Grants-in-Aid for Scientific Research
    2008 - 2010
    ITO Hiroyuki, FUJITA Osamu
    Combustion synthesis of carbon nanotube (CNT), in which thermal plasma is coexist with heat and carbon sources, is expected to make the mass production of CNT with low cost possible. It has been found that the CNT growth in this method is promoted by applying the direct current electric field. In this study, the effect of electric field on the change in temperature, concentration of chemical species of the CNT formation field, the amount and characteristics of the CNT formed are investigated. The effect of electric field on the CNT growth in the electric furnace is also investigated. As a result, the promotion of CNT growth and improvement of crystallization of CNT are observed in the combustion synthesis. It is suggested that the effect of electric field on the CNT manufacturing in the combustion synthesis can be ascribed to the increase in collection of CNT formed due to the motion of thermal plasma and the promotion of catalytic activity.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 20560176
  • レーザー加熱法を用いた火炎面曲率制御による火炎不安定現象の研究
    科学研究費補助金基盤研究（Ｂ）
    Apr. 2006 - Mar. 2009
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • 微小重力燃焼研究に基づく地下空間火災安全に関する基礎研究　　　　　　　　　　　　　　　
    科学研究費補助金基盤研究（Ｃ）
    Apr. 2004 - Mar. 2005
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • 微小重力環境を利用した浮遊微小粒子群の火炎伝播および熱輸送特性　　　　　　　　　　　　　　　
    科学研究費補助金基盤研究（Ｃ）
    Apr. 1995 - Mar. 1997
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • DME/メタノール混合燃料のエンジン適合性と環境負荷低減に関する燃焼学的検討
    科学研究費助成事業
    1996 - 1997
    伊藤 献一, 森川 多津子, 藤田 修
    近年その製法が確立され新たな代替燃料として期待されるDME(ジメチルエーテル)のディーゼルエンジンへの適用の可能性を知る上での基礎的データとしてその触媒反応性について検討を行った。
    前年度までの研究で、DME単体(ニート)あるいはDME/メタノール混合燃料を自動車用燃料として使用した場合を想定し、これらを燃料とする排ガスの触媒浄化に関する基礎的データを得てきた。とくに、NOx還元触媒(Co-γAl203やSn-γAl203)を利用し、酸素共存下での、これらの燃料成分やNOxの浄化特性について検討してきた。
    本年度は、新たに触媒として市販のリーンエンジン排ガス用触媒を用い、同様な実験を行った。この結果、DMEは100°C付近で浄化が開始し300°C以上ではほぼ100%近い浄化率を示した。ただし、この浄化率は排ガス中のNOx濃度に強く影響をうけ、NOxが250ppm程度共存すると、反応温度は100°CC以上高くなる。これとあわ、NOxが共存すると、反応過程でホルムアルデヒドの生成される可能性が示された。一方、NOxはかなり低温度条件から濃度低下が観察され、触媒への吸着作用の強いことがわかった。これらの実験結果から、すでに実用化の実績のある触媒で、ある程度DME排ガス浄化が可能であることが示された。このことは、DMEをジ-ゼル代替燃料として使用した場合、すすの発生がほとんどないことを考えあわせると、その排気を触媒との組み合わせで、十分浄化できる可能性のあることを示している。
    このほか、昨年からの使用しているNOx触媒あるいは酸化触媒(Pt-γAl203)を用いて、エンジン始動時等を想定した非定常実験も行い、触媒非定常作動特性に対し、触媒での吸着離脱現象が重要な役割を果たすことが示された。
    日本学術振興会, 基盤研究(B), 北海道大学, 08455097
  • 微小重力燃焼における機能性カーボン粒子の生成と構造　　　　　　　　　　　　　　　
    科学研究費奨励研究（Ａ）
    Apr. 1993 - Mar. 1994
    藤田 修
    日本学術振興会, Principal investigator, Competitive research funding
  • Combustion of solid material under microgravity -In case of porous material-
    Grants-in-Aid for Scientific Research
    1992 - 1994
    ITO Kenichi, TAZUMI Masahiro, FUJITA Osamu
    Natural convection caused by gravity field makes the combustion phenomena complicated. Since solid combustion is constituted by many physical processes, microgravity field is quite helpful to study its combustion processes through the elimination of natural convection.
    In the first year of this project microgravity experimental technique have been developed by using three types of drop tower, 5m, 50m and 500m drop towers. The flame propagation speed of cotton strings and paper sheet has been successfully measured.
    In the second year, the effect of various parameters, such as oxygen concentration, and dimension of test pieces have been investigated. The smaller amount of required oxygen, the higher propagation velocity. The higher oxygen concentration also gave the higher propagation velocity. The matrix of paper sheet, simulation of porous material, has also burned to examined the effect of pore size inside of the material, ventilation availability and oxygen concentration. Under microgravity these parameters except oxygen concentration did not affect to the flame propagation speed while they had strong effect under normal gravity. This is because these parameters have effect on the combustion through the change of natural convection strength inside the material.
    In the final year, the combustion of polystirene foam beads, which is made from a single chemical component have been investigated to hnow the dominant factors of porous material combustion. The results showed that flame spread phenomena of solid material is mainly dominated by the rates of heat supply to the unburned region and oxygen supply to combustion region. When the former factor, heat supply, is more dominant flame propagation is easier under microgravity because heat is not taken away by natural convection. When the later factor is dominant, flame propagation is faster under normal gravity with aid of natural convection to supply oxygen.
    Japan Society for the Promotion of Science, Grant-in-Aid for General Scientific Research (B), Hokkaido University, 04452143
  • 乱流拡散燃焼過程における可視長波長域発光現象と燃焼生成物
    科学研究費助成事業
    1990 - 1990
    伊藤 献一, 田住 正弘, 藤田 修
    燃料吹き出しを伴うブラフボディ後流拡散火炎を対象として、せん断層に形成される渦火炎の構造を、可視波長域発光現象および従来からの手法である温度変動、イオン電流変動、シュリ-レン写真撮影、ガス成分濃度分布測結果に基づいて、明らかにした。また、レ-ザ-誘起螢光法により、乱流火炎中のホルムアルデヒド濃度の非接触測定について検討した。これらの結果、以下のような成果が得られた。
    (1)せん断層に形成される火炎は明確な渦構造を有し、この構造は組織的かつ連続的にあらわれる。
    (2)この渦火炎においては、高温の燃焼ガスが過濃混合気を抱き込むようにしながら層状の渦構造を形成し、燃焼はこの渦内へ向かうような形で進行し最終的には均質な燃焼生成物の塊となる。
    (3)この均質化の過程において、渦内での独立した燃焼が進行するために周囲に酸素が存在していても局所的に不完全燃焼が生じることになる。とくに下流域においては、混合気の選択拡散の影響となり過濃燃焼となりやすく、不完全燃焼が生じやすい。これは、酸素過剰な条件における一酸化炭素の生成機構の一つであるとともに、濃淡燃焼によるNOxの抑制につながるものである。
    (4)火炎発光現象に基づく画像処理によって上記の濃淡燃焼の状況をとらえることができた。とくに、渦火炎の内部あるいは燃焼場の下流域において火炎の当量比が高くなる傾向にあることが確認できた。
    (5)レ-ザ-誘起螢光法により乱流火炎内のホルムアルデヒド濃度分布が測定できる可能性が示された。とくに、燃焼場が混合律速場であるか反応律速場であるかの違いをとらえることが可能であることが示された。
    日本学術振興会, 重点領域研究, 北海道大学, 02209201
  • 乱流拡散燃焼過程における可視長波長域発光現象と燃焼生成物
    科学研究費助成事業
    1989 - 1989
    伊藤 献一, 田住 正弘, 藤田 修
    本年度は、乱流拡散火炎の可視波長域発光現象の結果として生じる火炎色情報を利用することにより、比較的大規模な二次元渦火炎構造の観察を行った。このために以下に示す項目について検討を行い、同時に行われた成果についても示す。
    1.火炎色の定量化
    火炎色を定量的に表現することにより、火炎の色情報を燃焼計測のための一情報はとして利用可能とした。具体的には色彩学法に基づいて火炎色をCIE等色関数に基づく色度座標(X,Y,Z)により表現することが可能となった。
    2.火炎色と空気比あるいはラジカル濃度分布との関連性の検討
    火炎色は、反応帯に存在するラジカルの発光や化学反応の結果として生じるために、ラジカル濃度分布や空気比と関連性をもつことが予想される。この関連性について検討した結果、プロパンを燃料とした場合、色度座標は空気比に対して一意的に変化し火炎色から空気比の予測が可能であることが示された。また、火炎の発光源が限られている場合には火炎中のラジカル発光強度分布を予測できる可能性が示された。
    3.火炎色による乱流火炎構造の観察
    (1)乱流拡散火炎の基本特性の把握 本年度は、ブラフボディ後流に形成される拡散火炎を対象とし、とくに再循環領域と主流の境界せん断領域に形成される渦火炎に注目した。この構造を高速度シュリ-レン像、温度変動、イオン電流変動により観察しその火炎構造の規則性あるいは火炎の渦構造を明らかにした。
    (2)火炎色による乱流火炎構造の観察 上記の火炎を対象とし火炎色による火炎構造の観察を行なった。渦火炎中の空気比分布などの推定を行い、(1)で得られた結果と矛盾のない分布であることが示された。
    日本学術振興会, 重点領域研究, 北海道大学, 01627501
  • 乱流拡散燃焼過程における可視長波長域発光現象と燃焼生成物
    科学研究費助成事業
    1988 - 1988
    伊藤 献一, 田住 正弘, 藤田 修
    1〕目的: 本研究は火炎の分光スペクトルをもとに、色彩学的取扱いにより火炎色を数量にして表現し、火炎色と燃焼過程の関連性を解明することにある。対象として可視長波長域発光現象を取上げた。
    2〕手法: 水素、メタノール、炭火水素の各種火炎を対象とし、(1)分光スペクトルの測定、(2)等色関数を用い、色刺激に相当する三刺激値および刺激和を求める。(3)これらの色度座標を決定する。
    3〕知見: 火炎色の数量化手法により、水素火炎およびメタノール火炎にみられる可視長波長域発光現象の解析を行なった。その結果、H┣_<2┫>O分子による700nm域の赤色発光の寄与は少なく、むしろ、燃焼用空気中あるいは燃料中に含まれる微量Naによる線スペクトルと、Co炎バンドによる連続スペクトルとの混色発光が主因であることを明らかにできた。また、炭化水素予混合火炎に対して、火炎色と当量比の関連を色度図上に表すことを試み、当量比土0.01〜0.05の精度で識別が可能であることを見出した。
    4〕検討中の事項および今後の課題:(1)火炎色のより詳細な基礎特性の把握 (2)カラー画像処理による火炎色の実時間測定 (3)発光強度を考慮した火炎色の表現 (4)反応機構と火炎色との関連性の解明 (5)工学的応用を含めた火炎色彩学の確立
    5〕まとめ:本研究の成果は次のようにまとめられる。
    (1)火炎色を色度座標で数値的に表現した。
    (2)水素およびメタノール火炎にみられる可視長波長域発光現象には、空気中および燃料中に含まれるNaの熱発光が重要な役割を果している。
    (3)火炎色数値比の工学的応用の第一歩として、炭化水素予混合火炎における当量比計測の可能性を示した。
    (4)火炎色彩学という新分野を拓くことの可能性が認められた。
    日本学術振興会, 重点領域研究, 北海道大学, 63627501

Industrial Property Rights

  • 成型固体バイオマス燃料の燃焼装置　　　　　　　　　　　　　　　
    Patent right
    特願2011-027133