关键词: 排气系统;多喷嘴引射器+;启动;性能;第二喉道+;盲腔压力+;高空模拟试车台+

Abstract: At the expense of some pressure recovery performance,multi-nozzle ejector penetrates primary flows more deeply into secondary flows and decreases the transverse mixing distance greatly,which is substantial to the miniaturization of large-scale supersonic ejector.Using hot rocket exhaust gases as primary driving fluids,variety of multi-nuzzle ejectors were tested and the starting performances were obtained.Experimental results showed that in contrast with the central or annular ejector,multi-nozzle ejector requires bigger second throat area and higher minimum starting pressure due to additional pressure loss.Investigation indicated that the more ejector nozzles,the higher duct Mach number and/or nozzle exit Mach number,the higher minimum starting pressure is required.It was also found that higher nozzle exit Mach number tends to produce lower cell pressure and secondary flow can act as a booster,which can improve the multi-nozzle ejector starting performance.

Key words: Exhaust system;Multi-nozzle ejector+;Starting;Performance;Second throat+;Cell pressure+;High altitude test facility+