串联型脉冲喷嘴的实验研究

The Experimental Study on the Series Pulsed Nozzle

根据水声学原理和瞬变流理论,在自激振荡脉冲射流喷嘴的基础上,设计了一种新型的串联型脉冲喷嘴,它由Helmholtz谐振腔和风琴管谐振腔串联组成。实验选用3种不同形状碰撞壁风琴管,采用SD150测试系统,分析了串联型脉冲射流动态特性和形状变化对脉冲射流特性的影响规律,以及泵压和风琴管振荡腔长对射流冲蚀效果的影响。实验结果显示:如果两振荡腔结构参数选择合理,使其固有频率耦合,射流将能激励出更大的流体振荡,射流的瞬时能量将得到更大提高;3种碰撞壁中,冲蚀效果最佳的是球面形碰撞壁风琴管串联型脉冲喷嘴。

A new series pulsed nozzle, which is composed of the Helmholtz and organ pipe oscillation cavity, is designed on the basis of self-oscillating pulsed nozzle according to hydro-acoustics and fluid dynamics. The impinging wall of three typical shapes are chosen in the experiment. The SDI50 test system is used for analyzing the effects of parameters on the jet oscillating trait, analyzing the effect of the change in impinging wall shape on pulsed jetting characteristics and the effects of the pump pressure and the length of the organ pipe oscillation cavity on the jet impact pressure. Experimental results show that the jet will inspirit a stronger oscillating fluid and the instantaneous energy of the jet will be enhanced more largely if the parameters of the two oscillating cavities are well designed and their inherent frequencies of the two oscillating cavities are mutually coupled. The experiment also shows that the series pulsed nozzle of spherical impinging wall has the strongest erosion ability among the three tested impinging wall.