Space Technology Research Group, National Aerospace Laboratory(NAL)
Kakuda Branch Office, National Aerospace Laboratory(NAL)
Kakuda Branch Office, National Aerospace Laboratory(NAL)
Kakuda Branch Office, National Aerospace Laboratory(NAL)
National Space Development Agency of Japan(NASDA)
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-710
巻
710
ページ
30
発行年
1982-05
抄録(英)
The development of a 10-ton thrust liquid oxygen(LOX)and liquid hydrogen(LH2) rocket engine(LE-5) has been conducted by the National Space Development Agency(NASDA). National Aerospce Laboratory(NAL) has carried out research and development of the turbopumps for the LE-5 engine in co-operation with NASDA. In connection with the development of the LH2 turbopump, studies of liquid hydrogen rotating shaft seals, a face-contact metal bellows mechanical seal and floating-ring seal were performed. This paper describes the research and development of a floating-ring seal for the LH2 turbopump. The floating-ring seals tested were a double ring seal and a single ring seal. The seal diameter was 32 mm and the dimetral clearances were from 24.5 to 86 μm. The testing was performed under the following conditions: fluid pressures of 15 ata and 19 ata, and rotating speed of 50,000rpm. The seal performance was satisfactory under the test conditions and it was confirmed that the floating-ring seal has high-reliability for application to the LH2 turbopump. The leakage characteristics of the floating-ring seal were as follows. When the fluid in the seal clearance was liquid, the leakage rate obtained in the experiment agreed well with the result of incompressible flow calculation. However, when liquid hydrogen in the seal clearance was vaporized due to the pressure drop, the leakage rate was largely reduced compared with the result of incompressible flow calculation. The technical data obtained in this research and development was used in designing a LH2 floating-ring seal for a hydraulic pump turbine for the LE-5 engine.