Kakuda Research Center, National Aerospace Laboratory(NAL)
Space Technology Research Group, National Aerospace Laboratory(NAL)
Kakuda Research Center, National Aerospace Laboratory(NAL)
Kakuda Research Center, National Aerospace Laboratory(NAL)
Kakuda Research Center, National Aerospace Laboratory(NAL)
National Space Development Agency of Japan(NASDA)
Ishikawajima-Harima Heavy Industries Co., Ltd.
出版者
航空宇宙技術研究所
出版者（英）
National Aerospace Laboratory(NAL)
雑誌名
航空宇宙技術研究所報告
雑誌名(英)
Technical Report of National Aerospace Laboratory TR-1123
A small high-speed liquid hydrogen (LH2) pump was designed, fabricated, and tested in order to obtain technical data necessary for the development of upper stage rocket engines, e.g., the LE-5 and orbiter transfer vehicle (OTV) engines. The pump's basic mechanical design is described, as well as its mechanical performance during tests using LH2; both at nominal operating and rapid start/stop conditions. It was confirmed that the same materials employed for liquid oxygen pump components can be used, except for the impeller. An impeller made of titanium alloy (Ti-5Al-2.5Sn) was machined and then diffusion-bonded, and subsequently withstood a high speed operating condition (50,000 rpm) for 350 s. A balance piston configuration was selected for axial thrust control, where the impeller acts as a balance disk. The piston′s performance was satisfactory, although the impeller′s balance position during the tests was different from design calculations. Post-test examinations revealed light rubbing traces on the impeller and casing at the balance piston orifice. This positional discrepancy was caused by an inaccurate estimate of the orifice flow coefficients and leakage flow rate. Stress analysis on other components and machine specifications for critical mating parts were also verified as satisfactory. Self-lubricated ball bearings and rotating shaft seals showed adequate performance. Results indicate that smooth operation was achieved, thus confirming the soundness of the pump′s mechanical design.
ロケット用小型LH2ポンプの研究試作(その2)構造基本設計
naltr01123.pdf
(3MB)
