第二喉道超声速引射器启动性能理论研究

为了给带第二喉道的超声速引射器的工程设计提供设计依据,提出了一套快速分析其启动性能的方法.该方法采用特征线方法分析一次流喷嘴出口流场,结合Korst再压缩判据确定引射器盲腔压力,采用一维控制体方法计算第二喉道引射器的下游流场.采用该方法可以较好地估计第二喉道极限面积比、最小启动压比以及对应的盲腔压力.研究了一次流物性参数比热比和3个几何参数对引射器启动性能的影响.结果表明:该启动性能分析方法具有较好的一致性;较低的盲腔压力对应较高的最小启动压比. 

Theoretical investigation on starting performance of supersonic ejector with secondary throat

A set of fast analysis methods for starting performance of second-throat supersonic ejector was presented.The method of characteristics was introduced to calculate the flow field after the primary nozzle exit,whilst Korst's recompression criterion was adopted to determine the corresponding cell pressure,and one-dimensional control volume method was employed to analyze the downstream flow field.The second-throat area ratio limit,the minimal starting pressure ratio and the corresponding cell pressure were obtained.The influences of primary flow specific heat ratio and three geometric parameters on the starting performance were investigated.The results indicate that lower cell pressure leads to higher minimal starting pressure ratio,and the consistency of the method is quite well.