著者

東野 和幸 杉岡 正敏 小林 隆夫 境 昌宏 湊 亮二郎 笹山 容資 大塚 雅也 沖田 耕一 青木 賢司 川島 秀人 東 伸幸

出版者

一般社団法人 日本航空宇宙学会

雑誌

日本航空宇宙学会論文集 (ISSN:13446460)

巻号頁・発行日

vol.57, no.670, pp.445-452, 2009 (Released:2009-11-25)

参考文献数

10

被引用文献数

2 4

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Liquified Natural Gas (LNG) is one of the most promising propellant for near future space transportation rocket engine because of its low cost and fewer handling concerns. However, for LNG propellant, erosion of engine material by sulfur (sulfur attack) and coking by LNG pyrolysis are significant problems in a regenerative cooling passage. In this study, the effects of sulfur attack and coking are experimentally evaluated for material candidates such as Inconel600, SUS316, Hastelloy-X, and some copper alloys. In the sulfur attack tests, EPMA and Raman analysis indicate that metallic sulfide can be observed only on the surface and XRD analysis indicates that sulfur attack are hardly recognized for all of material in the test conditions. In coking tests, it is clear that coking of methane with 5% propane can proceed more than those of pure methane. The thermal decomposition temperature is significantly decreased by catalytic effects of Ni in engine material. The results of coking tests will be included in the design criteria of combustion chamber, nozzle of the LNG rocket engines.

著者

岩田 和也 松山 新吾 小島 淳 布目 佳央 川島 秀人 丹野 英幸 水書 稔治

出版者

一般社団法人 日本燃焼学会

雑誌

日本燃焼学会誌 (ISSN:13471864)

巻号頁・発行日

vol.62, no.200, pp.94-102, 2020 (Released:2020-06-13)

参考文献数

24

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Japan Aerospace Exploration Agency has now been working to understand detailed morphologies of detonation wave encountered in Rotating Detonation Rocket Engine (RDRE), which is one of the most potential engine concepts for light-weight and compact rocket system, and to investigate how they influence thrust performance and operational stability of the engine. Combustion experiments of an annular RDRE propelled by gaseous methane and oxygen were conducted to measure thrust performance and to visualize detonation propagation and CH*/OH* chemiluminescence, from which specific thrust was revealed close to the theoretical value with stable propagation modes, and without throat contraction. CH* chemiluminescence also indicated deflagrative combustion anchoring at the injection plane, which could partly explain the performance degradation in a configuration with throat. Experimentally observed detonation velocity ranged 45-75 % of Chapman-Jouguet (C-J) velocity, which was partly confirmed to be induced by incomplete mixing from the results of two/three-dimensional simulation employing detailed chemical kinetics. However, numerically predicted velocity was higher by several tens of percentage, indicating potential influence of thermal/viscous loss to the confinement. Overall, physical insight was achieved into non-ideal behavior of detonation including strongly curved wave front induced by incomplete mixing and our findings emphasizes a need for better mixing techniques to achieve more ideal characteristics of detonation.