Search

Your search keyword '"Tani, Hiroumi"' showing total 44 results
Start Over Author "Tani, Hiroumi"
44 results on '"Tani, Hiroumi"'

8. Multilayer reaction zones of a counterflow flame of gaseous Nitrogen Tetroxide and a liquid Monomethylhydrazine pool

Author

Gabl, Jason, Black, Ariel, Pourpoint, Timothee, Hayashi, Jun, Tani, Hiroumi, Kanno, Nozomu, Sato, Daisuke, Daimon, Yu, and Akamatsu, Fumiteru

Subjects
Reaction mechanism, Materials science, Nitrogen tetroxide, General Chemical Engineering, Flame structure, Analytical chemistry, General Physics and Astronomy, Energy Engineering and Power Technology, 02 engineering and technology, 01 natural sciences, Chemical reaction, Chemical kinetics, chemistry.chemical_compound, Counterflow pool flame, 020401 chemical engineering, 0103 physical sciences, Monomethylhydrazine, 0204 chemical engineering, 010304 chemical physics, Hypergolic propellants, Gaseous nitrogen, General Chemistry, Fuel Technology, chemistry, Light emission
Abstract

形態: カラー図版あり, Physical characteristics: Original contains color illustrations, Accepted: 2018-12-25, 資料番号: PA1910057000

Published
2019

9. Experimental analysis of the spreading of a liquid film on a bipropellant thruster chamber wall

Author

60273471, Sako, Noritaka, Hayashi, Jun, Daimon, Yu, Tani, Hiroumi, Kawanabe, Hiroshi, 60273471, Sako, Noritaka, Hayashi, Jun, Daimon, Yu, Tani, Hiroumi, and Kawanabe, Hiroshi

Abstract

In film cooling approaches, a film of liquid fuel is formed on the chamber wall of bipropellant thrusters to protect the chamber wall from high-temperature combustion gases. To optimize the amount of liquid fuel required to sufficiently cool a chamber wall in this manner without degrading the performance of bipropellant thrusters, the formation process of the liquid film needs to be understood. To this end, in this study, factors affecting the spread of liquid film were experimentally investigated. In particular, experimental apparatus that could reproduce the state of a liquid jet being injected onto a wall to form a liquid film was developed. Water was used as the test liquid because hydrazine-derivative fuels, which are generally used in bipropellant thrusters, are toxic, and the density and surface tension of water are similar to those of hydrazine. The liquid film formation processes were visualized and analyzed by using a still camera. Results indicated that the liquid jet velocity, nozzle diameter, and impingement angle were the key factors affecting the film width, and the maximum film width exhibited a linear relation to the liquid jet velocity component perpendicular to the wall. Considering these results, a general relationship between the key factors and maximum film width was identified, and it was noted that the dimensionless maximum film width could be defined as the product of the Weber number and sine value of the impingement angle. In this manner, the maximum film width can be predicted when deciding injection conditions, which can assist thruster designers during the design process.

Published
2021

13. Interface Tracking Simulations of Liquid Rocket Engine Combustion at Subcritical Pressures

Author

Tani, Hiroumi, Daimon, Yu, Umemura, Yutaka, and Negishi, Hideyo

Abstract

第48回流体力学講演会/第34回航空宇宙数値シミュレーション技術シンポジウム (2016年7月6日-8日. 金沢歌劇座), 金沢市, 石川, 48th Fluid Dynamics Conference /the 34th Aerospace Numerical Simulation Symposium (July 6-8, 2016. The Kanazawa Theatre), Kanazawa, Ishikawa, Japan, A feasibility study of the interface tracking simulations of liquid oxygen (LOX) and gaseous hydrogen(GH2) coaxial combustion at a subcritical pressure was conducted. To simulate the breakup and atomization of LOX core, CIP-LSM (Constrained Interpolation Profile based Level Set and MARS) that combined CIP-CUP (CIP-Combined Unified Procedure) method with the hybrid Level-set and MARS (Multi-interface Advection and Reconstruction Solver) method for volume tracking, was employed as a solver of the governing equations of fluids. The phase change rate on the surfaces between the multi-species gas and single-species liquid was calculated. To investigate the ignition process and flame holding mechanism, chemical reaction equations were solved with the detailed chemical mechanism of oxygen and hydrogen. Results suggested that this numerical approach can be a powerful method that provides the information on ignition, breakup and atomization of LOX core, and flame holding at the steady state of LOX/GH2 coaxial combustion at subcritical pressures., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1630031027, レポート番号: JAXA-SP-16-007

Published
2016

14. ロケット・宇宙機エンジンの燃焼解明と高精度性能評価を目指した反応熱流体解析技術 : 内燃機関燃焼解析技術のブレークスルー

Author

Inoue, Chihiro, Terashima, Hiroshi, Tani, Hiroumi, Morii, Youhi, and Daimon, Yu

Abstract

東京大学ロケット・宇宙機モデリングラボラトリー(社会連携講座)シンポジウム (2016年3月23日. 宇宙航空研究開発機構筑波宇宙センター(JAXA)(TKSC) ), つくば市, 茨城, 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1630026003, レポート番号: JAXA-SP-16-005

Published
2016

15. 小特集: 宇宙開発におけるCFDの課題

Author

Tani, Hiroumi, Ohmari, Tetsufumi, Tiakata, Shinich, Uematsu, Hirohiko, Matsuura, Mayumi, Daimon, Yu, and Negishi, Hideyo

Subjects
Multi-model ensemble, Downscaling, Climate change adaptation, Urban economic model, Risk assessment
Abstract

形態: 図版あり, Physical characteristics: Original contains illustrations, 資料番号: AC1600002000

Published
2015

16. 小特集: 宇宙開発におけるCFDの課題

Author

Daimon, Yu, Tani, Hiroumi, Terashima, Hiroshi, Kanno, Nozomu, Koshi, Mituo, and Negishi, Hideyo

Subjects
Hypergolic Propellant, Hydrazine, Small Thruster for Space Craft, Numerical Combustion Simulation
Abstract

形態: 図版あり, Physical characteristics: Original contains illustrations, 資料番号: AC1600005000

Published
2015

17. Double flame structure of hydrazine/nitrogen dioxide coaxial jets

Author

Tani, Hiroumi, Terashima, Hiroshi, Koshi, Mituo, and Daimon, Yu

Abstract

第46回流体力学講演会/第32回航空宇宙数値シミュレーション技術シンポジウム (2014年7月3日-4日. 弘前文化センター), 弘前市, 青森県, 46th Fluid Dynamics Conference / 32nd Aerospace Numerical Simulation Symposium (July 3-4, 2014. Hirosaki Bunka Center), Hirosaki, Aomori, Japan, Hydrazine (N2H4) nitrogen dioxide (NO2) co-flowing plane jets were simulated to explore the flame structures in hypergolic N2H4 nitrogen tetroxide (N2O4) bipropellant thrusters. The Navier-Stokes equations with a detailed chemical kinetics mechanism were solved in a manner of direct numerical simulation to reveal the interaction between fluid dynamics and the distinct chemical reaction, i.e. hydrogen abstraction by nitrogen dioxide (NO2) and the thermal decomposition of N2H4. The combustion flames uniquely comprised two types of flames, the diffusion flame and the decomposition flame. The diffusion flame came from the oxidization by NO2. The decomposition flame was caused by the heat transfer from the diffusion flame and a high rate of heat release from the thermal decomposition of N2H4. Owing to the decomposition flame, the decomposition products such as NH3, N2 and H2 became the major constituents of the downstream combustion gases., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1530023014, レポート番号: JAXA-SP-14-010

Published
2015

18. Experiment of high-pressure (90MPa) hydrogen leakage diffusion, combustion, and explosion

Author

Kobayashi, Hiroaki, Naruo, Yoshihiro, Maru, Yusuke, Takesaki, Yuichiro, Sugino, Shinya, Sato, Mamoru, Yagishita, Tsuyoshi, Daimon, Yu, Tani, Hiroumi, Umemura, Yutaka, Muto, Daiki, Matsumoto, Mayu, Tsujigami, Hiroshi, Miyanabe, Kota, Yoshino, Yuu, and Kawamura, Satoru

Subjects
Renewable Energy, Hydrogen, In Situ Resource Utilization
Abstract

平成29年度宇宙輸送シンポジウム（2018年1月18日-19日. 宇宙航空研究開発機構宇宙科学研究所（JAXA)(ISAS)）, 相模原市, 神奈川県, Space Transportation Symposium FY2017 (January 18-19, 2018. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000210024, レポート番号: STCP-2017-024

Published
2018

19. New Horizons of Reactive Flow Simulation

Author

Koshi, Mitsuo, Terashima, Hiroshi, Tani, Hiroumi, and Daimon, Yui

Subjects
Hypergolic ignition, Knocking, Thruster, Chemical Kinetics, CFD
Abstract

平成28年度衝撃波シンポジウム (2017年3月8日-10日. ヴェルクよこすか 横須賀市立勤労福祉会館）横須賀市, 神奈川県, Symposium on Shock Waves in Japan, FY2016 (March 8-10, 2017. Werk Yokosuka), Kanagawa, Japan, 資料番号: SA6000084003, レポート番号: 特別講演 II

Published
2017

22. ロケットエンジンシミュレーションにおける今後の展望

Author

Yamanishi, Nobuhiro, Negishi, Hideyo, and Tani, Hiroumi

Abstract

東京大学ロケットエンジンモデリングラボラトリー(JAXA社会連携講座)シンポジウム (2012年9月26日-27日. 東京大学), 東京, Symposium on Rocket Engine Modeling Laboratory, The University of Tokyo (JAXA public relations lecture): Advances in Rocket Engine Modeling and Simulation, and its Future (September 26-27, 2012. The University of Tokyo), Tokyo Japan, 形態: カラー図版あり, 共催: 東京大学ロケットエンジンモデリングラボラトリー(JAXA社会連携講座), 宇宙航空研究開発機構, Physical characteristics: Original contains color illustrations, Meeting sponsors: Rocket Engine Modeling Laboratory, The University of Tokyo (JAXA public relations lecture), JAXA's Engineering Degital Innovation Center, Japan Aerospace Exploration Agency (JAXA)(JEDI), Translation title: Future prospects of research in numerical simulation of rocket engine, 資料番号: AA0061924018, レポート番号: JAXA-SP-12-014

Published
2013

27. ロケット・宇宙機エンジンの燃焼解明と高精度性能評価を目指した反応熱流体解析技術 : 内燃機関燃焼解析技術のブレークスルー

Author

井上, 智博, 寺島, 洋史, 谷, 洋海, 森井, 雄飛, 大門, 優, Inoue, Chihiro, Terashima, Hiroshi, Tani, Hiroumi, Morii, Youhi, Daimon, Yu, 井上, 智博, 寺島, 洋史, 谷, 洋海, 森井, 雄飛, 大門, 優, Inoue, Chihiro, Terashima, Hiroshi, Tani, Hiroumi, Morii, Youhi, and Daimon, Yu

Abstract

会議情報: 東京大学ロケット・宇宙機モデリングラボラトリー(社会連携講座)シンポジウム (2016年3月23日. 宇宙航空研究開発機構筑波宇宙センター(JAXA)(TKSC) ), つくば市, 茨城, 形態: カラー図版あり, Physical characteristics: Original contains color illustrations

Published
2016

29. SPICA衛星のコンタミネーション管理: リスク低減フェーズ#2での活動

Author

SPICAコンタミネーションワーキンググループ, Isobe, Naoki, Nakagawa, Takao, Okazaki, Shun, Sato, Yoichi, Ando, Makiko, Baba, Susumu, Miura, Yuka, Miyazaki, Eiji, Kimoto, Yugo, Ishizawa, Junichiro, Tani, Hiroumi, Urayama, Fumitaka, and SPICA, Contamination Working Group

Abstract

第14回宇宙科学シンポジウム (2014年1月9日-10日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 14ｔh Space Science Symposium (January 9-10, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 著者人数: 12名, 資料番号: SA6000058083, レポート番号: P2-051

Published
2014

30. A Numerical Study on Hypergolic Combustion of Hydrazine Sprays in Nitrogen Tetroxide Streams.

Author

Tani, Hiroumi, Terashima, Hiroshi, Daimon, Yu, Koshi, Mitsuo, and Kurose, Ryoichi

Subjects
HYDRAZINE, NITROGEN tetroxide, NUMERICAL solutions to Navier-Stokes equations, CHEMICAL kinetics, EVAPORATION (Chemistry), CHEMICAL decomposition
Abstract

Unsteady simulations of hydrazine (N2H4) sprays in nitrogen tetroxide (NTO, NO2-N2O4) streams were conducted to explore the hypergolic combustion in bipropellant thrusters. The Navier–Stokes equations were solved using a detailed chemical kinetics mechanism and dispersed droplets were modeled through direct numerical simulations. Auto-ignition occurred when the sum of the heat transfer from the ambient gas and the heat release from hydrogen abstraction reactions exceeded the latent heat of the droplets. Although the evaporation of the droplets was enhanced as the droplet size decreased, the ignition delay time increased due to the lower temperatures of the mixtures of the N2H4vapor and nitrogen tetroxide. After the flames reached a steady state, a double flame structure appeared, comprised of outer diffusion and inner decomposition flames. The inner decomposition flame and N2H4vapor flow exhibited a sinusoidal behavior at a certain droplet size. This behavior was initiated by the locally expanded decomposition gases and developed by the supply of N2H4droplets to the decomposition gases at relatively high temperatures. In cases of larger and smaller droplet sizes, the sinusoidal behavior was not significant due to less evaporation of the N2H4droplets and a lower temperature of the N2H4vapor, respectively. The sinusoidal behavior of the decomposition flames enhanced the mixing and reactions of the fuel components (i.e., N2H4, NH3, and H2). The present study demonstrated a large impact of droplet size on flame dynamics, suggesting that a fine spray is not always better for hypergolic propellant combustion to consume the fuel components quickly. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

31. SLIM推進系の高性能化に向けた研究

Author

Nakatsuka, Junichi, Sawai, Shujiro, Sato, Eiichi, Daimon, Yu, Tani, Hiroumi, Yamanishi, Nobuhiro, Morishima, Katsushige, and Furukawa, Katsumi

Abstract

第13回宇宙科学シンポジウム (2013年1月8日-9日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 13th Space Science Symposium (January 8-9, 2013. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 資料番号: SA6000063187, レポート番号: P2-160

Published
2013

34. ヒドラジン/二酸化窒素同軸噴流の特異な二重火炎構造

Author

谷, 洋海, 寺島, 洋史, 越, 光男, 大門, 優, Tani, Hiroumi, Terashima, Hiroshi, Koshi, Mituo, Daimon, Yu, 谷, 洋海, 寺島, 洋史, 越, 光男, 大門, 優, Tani, Hiroumi, Terashima, Hiroshi, Koshi, Mituo, and Daimon, Yu

Abstract

Hydrazine (N2H4) nitrogen dioxide (NO2) co-flowing plane jets were simulated to explore the flame structures in hypergolic N2H4 nitrogen tetroxide (N2O4) bipropellant thrusters. The Navier-Stokes equations with a detailed chemical kinetics mechanism were solved in a manner of direct numerical simulation to reveal the interaction between fluid dynamics and the distinct chemical reaction, i.e. hydrogen abstraction by nitrogen dioxide (NO2) and the thermal decomposition of N2H4. The combustion flames uniquely comprised two types of flames, the diffusion flame and the decomposition flame. The diffusion flame came from the oxidization by NO2. The decomposition flame was caused by the heat transfer from the diffusion flame and a high rate of heat release from the thermal decomposition of N2H4. Owing to the decomposition flame, the decomposition products such as NH3, N2 and H2 became the major constituents of the downstream combustion gases., 会議情報: 第46回流体力学講演会/第32回航空宇宙数値シミュレーション技術シンポジウム (2014年7月3日-4日. 弘前文化センター), 弘前市, 青森県, 形態: カラー図版あり, Meeting Information: 46th Fluid Dynamics Conference / 32nd Aerospace Numerical Simulation Symposium (July 3-4, 2014. Hirosaki Bunka Center), Hirosaki, Aomori, Japan, Physical characteristics: Original contains color illustrations

Published
2015

41. Contamination control for the space infrared observatory SPICA

Author

Isobe, Naoki, additional, Nakagawa, Takao, additional, Okazaki, Shun, additional, Sato, Yoichi, additional, Ando, Makiko, additional, Baba, Susumu, additional, Miura, Yuka, additional, Miyazaki, Eiji, additional, Kimoto, Yugo, additional, Ishizawa, Junichiro, additional, Tani, Hiroumi, additional, Maruyama, Kenta, additional, Urayama, Fumitaka, additional, and Mori, Akihito, additional

Published
2014
Full Text
View/download PDF

43. Computational Study of the Rate Coefficients for theReactions of NO2with CH3NHNH, CH3NNH2, and CH2NHNH2.

Author

Kanno, Nozomu, Tani, Hiroumi, Daimon, Yu, Terashima, Hiroshi, Yoshikawa, Norihiko, and Koshi, Mitsuo

Subjects
*NITROGEN dioxide, *ISOMERIZATION, *RATE coefficients (Chemistry), *QUANTUM theory, *RICE-Ramsperger-Kassel theory, *TRANSITION state theory (Chemistry)
Abstract

Thereactions of NO2with cis-/trans-CH3NHNH, CH3NNH2andCH2NHNH2have been studied theoretically byquantum chemical calculations and steady-state unimolecular masterequation analysis based on RRKM theory. The barrier heights for theroaming transition states between nitro (RNO2) and nitrite(RONO) isomerization reactions and those for the concerted HONO andHNO2elimination reactions from RNO2and RONO,affect the pressure dependences of the product-specific rate coefficients.At ambient temperature and pressure, the dominant product of the reactionsof NO2with cis-/trans-CH3NHNH and CH2NHNH2would be expectedto be HONO with trans-CH3NNH and CH2NNH2, respectively, whereas it is CH3N(NH2)NO2for CH3NNH2+ NO2. The product-specific rate coefficients for thetitled and related reactions on the same potential energy surfaceswere proposed for kinetics modeling. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

44. Contamination control for the space infrared observatory SPICA

Author

Oschmann, Jacobus M., Clampin, Mark, Fazio, Giovanni G., MacEwen, Howard A., Isobe, Naoki, Nakagawa, Takao, Okazaki, Shun, Sato, Yoichi, Ando, Makiko, Baba, Susumu, Miura, Yuka, Miyazaki, Eiji, Kimoto, Yugo, Ishizawa, Junichiro, Tani, Hiroumi, Maruyama, Kenta, Urayama, Fumitaka, and Mori, Akihito

Published
2014
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results