研究者詳細 - 河内　俊憲

講演・口頭発表等 - 河内　俊憲

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Pulsed transverse injection applied to a supersonic flow

Toshinori Kouchi, Noboru Sakuranaka, Muneo Izumikawa, Sadatake Tomioka

Collection of Technical Papers - 43rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference 2007年

開催年月日： 2007年

An experimental investigation was conducted to reveal jet penetration and mixing performance of pulsed injection in a Mach 2.5 crossflow. Helium and nitrogen gas were injected perpendicularly through flush-mounted circular sonic orifice. Probing techniques including species composition sampling and high speed framing schlieren were employed to determine the penetration and mixing performance at several downstream locations. Our investigation consisted essentially of two parts. The first part was an investigation of the continuous jet. The performance of the continuous jet was mainly controlled by effective velocity ratio (r) as the square root of the momentum-flux ratio and the orifice diameter (d). The centerline trajectories of the jets and the maximum concentration decay were collapsed by the rd scale and the ratio of oncoming boundary-layer thickness to the injector diameter. The second part was an comparison of the performance between the pulse and continuous jets. The penetration of the pulse jet was adjustable by changing the pulse duty cycle at a condition of fixed injectant mass flow rate. Even at a condition of fixed injection pressure, the pulsed injection showed better mixing performance and the higher penetration, due to the fluctuation of the large-scale eddies in the jet associated with the fluctuation of the bow shock in front of the jet.

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超音速燃焼器における燃料噴射孔形状が貫通に及ぼす影響の検討(空気力学・高エンタルピー流(2),一般講演)

平野昂志, 河内俊憲, 小池俊輔, 泉川宗男, 松尾亜紀子, 富岡定毅, 升谷五郎

日本流体力学会年会講演論文集 2007年日本流体力学会

開催年月日： 2007年

記述言語：日本語

Both the wind tunnel experiments and the numerical analyses on helium injections with various injector geometry configurations were performed in order to achieve high penetration and effective mixing between supersonic crossflow and injectant. The stinger shaped injector showed the best penetration performance among all injectors. There was a difference between the experiment and the numerical analysis in evaluation of the injectant concentration. However, the penetration height resulted from the numerical analysis showed good agreement with that from the experiment. It is believed that the reduction of the disturbance of the plume to the crossflow leads to the increment in the penetration.

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超音速流中への直列4孔噴射の貫通特性

小池俊輔, 河内俊憲, 泉川宗男, 富岡定毅, 升谷五郎

燃焼シンポジウム講演論文集 2007年

超音速燃焼器における燃料噴射孔形状が貫通に及ぼす影響の検討

平野昂志, 河内俊憲, 小池俊輔, 泉川宗男, 松尾亜紀子, 富岡定毅, 升谷五郎

日本流体力学会年会講演アブストラクト集 2007年

Evaluation of heat-flux on scramjet engine wall in Mach 6 flight condition

Shuichi Ueda, Masao Takegoshi, Toshinori Kouchi, Fumiei Ono, Toshihito Saito, Muneo Izumikawa

AIAA 57th International Astronautical Congress, IAC 2006 2006年

開催年月日： 2006年

Space transportation system uses the liquid hydrogen of the fuel as a coolant of the engine. Therefore, it is necessary to predict the heat flux to the engine wall in high accuracy for efficient cooling with a minimum coolant. However, the prediction of the heat flux to the scramjet engine combustor walls, is quite difficult due to complex interaction of flow and combustion. In this study, a sidewall-compression-type scramjet engine was tested under Mach 6 flight conditions using Ramjet Engine Test Facility. The heat flux was measured using water-cooled heat-flux meters installed on the sidewall within the combustor sections. The experimental results were compared with CFD analysis of the whole engine to predict heat flux distribution on the engine wall. The numerical results of wall pressure distribution showed good agreement with the experimental data. However, the experimental results of heat flux were extremely higher than the numerical results due to the radiation heating which was not considered in the CFD analysis. Based on the results, the average heat flux of the sub-scale scramjet engine with 300 K isothermal walls was 1 MW/m2 in the stoichiometric fuel rate at Mach 6 flight conditions.

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Heat Flux Prediction for Scramjet Engines

T. Kouchi, T. Mitani, T. Hiraiwa, M. Kodera, G. Masuya

Proceedings of 1st International Conference of Flow Dynamics 2004年11月

Scramjet performance achieved in engine tests from M4 to M8 flight conditions

Tohru Mitani, Sadatake Tomioka, Takeshi Kanda, Nobuo Chinzei, Toshinori Kouchi

12th AIAA International Space Planes and Hypersonic Systems and Technologies 2003年

開催年月日： 2003年

Thrust performances of scramjet engines were compared with theoretical values to quantify the progress in engine performances (defined as "achievement factors", or "factors") from Mach (termed as "M") 4 to M8 flight conditions. An engine with a ramp produced a net thrust of 215 N under the M8 tests and a comparison of a theoretical thrust yielded a thrust achievement factor of 51%. By excluding boundary layer, an engine with a thick strut delivered a net thrust of 560 N and showed a thrust factor of 92% and a net thrust factor of 45%. The thrusts were limited by flow separation caused by engine combustion (termed as "engine unstart"). The starting characteristics was improved by boundary layer controls in M6 and M4 conditions. An engine with a thin strut doubled the thrust from 1620 N to 2460 N by the boundary layer bleeding in the M6 tests. The improved thrust factor was 60% at the stoichiometric H2 condition. Under M4 tests, the net thrust was tripled by the bleed and a two-staged injection of H2. As results, the thrust factor was raised from 53% to 70%, the net thrust factor was increased from 32% to 55%. Studies required for improving the net performance was addressed. © 2003 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

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ステレオPIVを用いた超音速流れ場の境界層速度計測