自激振荡脉冲射流喷嘴频率特性实验研究

基于水声学和流体动力学原理,建立了振荡腔内脉冲射流频率模型,研究结果表明,模态数、流体密度及密度变化率是影响射流频率的关键因素。采用SD150测试系统,分析了自激振荡脉冲射流动态特性中各参数对其频率的影响程度,泵压和自激振荡腔长对射流频率影响的实验结果表明,脉冲射流幅值比连续射流提高了约20%;泵压升高,射流频率增加;腔长增大,射流频率降低,且存在一个使脉冲射流压力峰值达到最大的最佳腔长。实验结果与理论分析一致。

Experimental study on the frequency characteristic of the self-excited oscillation pulsed nozzle

The model of jet oscillation frequency was given on the basis of hydroacoustics and fluid dynamics. The SD150 test system was used to analyze the effects of dynamic parameters on the jet oscillation frequency. The effects of pump pressure and the length of the oscillation cavity on the jet oscillation frequency were studied. The test results showed that the peak value of the self-excited oscillation pulsed water jet is larger by about 200 than that of continuous jet. The oscillation frequency increased while increasing pump pressure and decreased while increasing the length of oscillation cavity. There was an optimum length of oscillation cavity corresponding to the pressure peak value of the self-excited oscillation pulsed water jet. Experimental result is in good agreement with that of theoretical analysis.