Kakuda Branch Office, 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)
Kakuda Branch Office, National Aerospace Laboratory(NAL)
Kakuda Branch Office, National Aerospace Laboratory(NAL)
Kakuda Branch Office, National Aerospace Laboratory(NAL)
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-493
巻
493
ページ
25
発行年
1977-03
抄録（英）
This report describes the results of experiments conducted to determine the effects of a subsonic diffuser attached to a second throat diffuser and ejector nozzle contour on ejector performance, without induced flow, for rocket engine altitude simulation. A reduction of more than 10％ in the starting and break down pressure ratio was found to be obrtainable by employing a conical subsonic diffuser having a 2.3 area ratio and 4 to 12 degree semiangle. The reduction in pressure ratios depended on the nozzle area ratio and the second throat length, as well as the semiangle of the subsonic diffuser. It was also found that in some configurations the flow at the subsonic diffuser inlet was partly supersonic and that in these cases pressure recovery in the subsonic diffuser was larger than that in the cases where the flow at the inlet was subsonic. The nozzle contour effect was studied by comparison of ejector performances between two otherwise identical configurations, one with a conical nozzle and the other with a contoured nozzle. Both nozzles were of approximately the same throat diameter and area ratio. In the configuration where the gap between the nozzle exit diameter and diffuser inlet diameter was large, the difference in ejector performance between the two configurations was found to be predictable. Important unfavourable results, i.e., increased limiting second throat contraction area ratio for starting, large hysteresis, and violent start and break down transients, were observed in the contoured nozzle-second throat diffuser configuration where the gap between nozzle exit diameter and diffuser inlet diameter was small. Experimental data on wall pressure distribution over the shock-separated region in the second throat and constant diameter diffuser are presented and discussed in the Appendix.
零2次流エゼクタにおける亜音速ディフューザおよびノズル形状の効果
naltr00493.pdf
(2.37MB)
