自激脉冲射流装置的压力特性分析

Pressure Characteristics Analysis of Self-excited Pulsed Jet Device

利用自行研制的试验系统对自激脉冲射流装置压力特性和打击力进行了试验研究,探讨了腔长和工作压力对射流打击力和脉冲效果的影响,研究了自激脉冲射流装置腔壁不同部位的压力变化特点和打击力变化特点。试验结果表明,当腔长较小时,装置在各个工作压力条件下均没有脉冲效果,随着腔长逐渐变大,逐渐产生脉冲效果,并在一定的工作压力范围内取得最佳脉冲效果;在射流核二侧形成的漩涡型空化气囊,是产生脉冲射流根本原因;当脉冲效果较好时,装置腔壁不同部位的压力与打击力变化呈现明显的周期性,但装置不同部位压力和打击力之间的变化周期并不同步。

Pressure characteristics and hitting power of self-excited pulsed jet device was studied by the independently developing testing system.The influence on hitting power and pulsing effect of cavity length and working pressure was researched.Pressure and hitting power variations of cavity wall different part for self-excited pulsed jet device was studied.The analysis result indicates that while cavity length is smaller the device has not pulsing effect under various working pressures;while cavity length becomes greater the device generates pulsing effect gradually and obtains optimum pulsing effect.The vortex-type cavitation gas bag is formed on two sides of jet core,and this is the basic reason for pulse jet generation.While pulsing effect is better the pressure and hitting power of different part for device cavity wall show obvious periodicity,but change cycle between the pressure and hitting power aren＇t in synchronization.