Abstract:

he oscillation characteristics of two planar opposed jets were studied by using high-speed camera, smoke wire visualization and hot-wire anemometry (HWA).The oscillation periods of two planar opposed jets at different nozzle separations and exit nozzle velocities were studied.The results showed two models of instabilities:streamwise quasi-periodic oscillation model and deflection oscillation model.The oscillation model was mainly streamwise quasi-periodic oscillation model at L<5H (where L was the nozzle separation and H was the nozzle slot height), and it was mainly deflection oscillation model at L>5H.The deflection oscillation model had a stable period which decreased with increasing normalized nozzle separation.

Key words:

平面喷嘴, 振荡特性, 撞击流, 烟线法, 流场显示

摘要：

对两对置平面喷嘴形成的撞击流的振荡特性进行了实验研究。采用高速摄像仪、烟线流场显示和热线测量的方法，研究了不同喷嘴间距、不同喷嘴出口气速下平面喷嘴撞击流的振荡行为。研究结果表明，平面撞击流的振荡特性主要有流向拟周期振荡和偏斜振荡两种，当L<5H时主要为流向拟周期振荡模式，当L>5H时主要为偏斜振荡模式。

关键词:

平面喷嘴, 振荡特性, 撞击流, 烟线法, 流场显示