多排径向通道直流喷嘴的声学特性试验研究

为了避免高压补燃循环氢氧发动机推力室中喷注耦合不稳定问题的发生,采用试验技术手段分析了多排径向通道直流喷嘴的声学特性,研究了径向通道孔径、径向通道数量、径向通道长度、喷嘴长度对喷嘴声学特性的影响规律。研究结果表明径向通道长径比和折合喷嘴长度是影响喷嘴声学频率的关键因素,并建立了无量纲喷嘴结构参数与声学频率间的经验关系式,为多排径向通道直流喷嘴的声学频率预估提供依据。

Experimental Study on Acoustic Characteristics of the Plain Orifice Nozzle with Multi-row Radial Channels

In order to avoid the problem of injected coupling instability in the thrust chamber of the hydrogen-oxygen staged combustion cycled engine,the acoustic characteristics of the plain orifice nozzle with multi-row radial channels are analyzed by experimental techniques.The influence of the radial channel diameter,the number of radial channels,the radial channel length and the nozzle length on the acoustic characteristics are studied.The results show that the depth-diameter aspect ratio of the radial channel and the reduced nozzle length are the key factors to the acoustic frequency of the nozzle,and the empirical relationship between the dimensionless structural parameters of the nozzle and the acoustic frequency is established,which provide the basis for acoustic frequency estimation of the plain orifice nozzle with multi-row radial channels.