水平对置双向液体撞击流的振荡特性

利用平面激光诱导荧光(PLIF)技术对水平对置双向液体撞击流流场进行了实验研究,考察了等动量下撞击面驻点在不同喷嘴间距、不同进液流量下的稳定性和振荡特性。结果表明,撞击面驻点的振荡并没有一个固定的周期,并且频率主要集中在低频,而其幅度集中在0.1d～0.5d范围内:在L∈1d,3d](L为喷嘴间距,d为喷嘴直径)范围内,振荡幅度随着L的增加而增大;在L∈3d,5d]范围内,振荡幅度随着L的增加而减小。同时,撞击面的振荡幅度并不会随着流速的增大而一直增大,而是在达到一个峰值后逐渐降低。撞击面驻点的这种振荡特性对混合和传质具有一定的促进作用。

Oscillation characteristics of two horizontal opposed liquid-liquid impinging streams

The flow field of two horizontal opposed liquid-liquid impinging streams was experimentally studied with the PLIF technology in order to investigate the stability of impingement plane and the oscillation characteristics of stagnation point at various nozzle separations and fluxes. Oscillation period was not regular and frequency concentrated on the low frequency region. While amplitude concentrated on 0.1d-0.5d. When L belonged to 1d, 3d] ( where L was nozzle separation and d was nozzle diameter ), amplitude increased with the growth of L, but when L belonged to 3d, 5d], amplitude decreased with the growth of L. The amplitude of impingement plane did not always grow up with increasing flux, which gradually decreased after reaching a peak. The oscillation characteristics of impingement plane and stagnation point were favorable to mixing and mass transfer.