应用PIV技术测试涡旋波流场

涡旋波流动作为一种特殊的流动现象,可以使流体在相对较宽的槽道中产生较强的波动和对流混合,从而在小Re数条件下起到强化传质的效果。本文利用PIV流场显示技术,对振荡流在非对称槽道中所形成的涡旋波的产生机理和发展规律进行了实验研究和定量分析,测得了涡旋波流场的速度矢量图,阐明了涡旋波流场周期性变化的特点。分析了Re数和St数对涡旋波流动的影响,并得出了旋涡涡心位置以及涡心处涡量的动态变化规律。

Investigation on the Characteristics of Vortex Wave Flow by PIV

As a kind of new discovered flow phenomena,the vortex wave flow causes a strong wavy flow and impressive convective mixture in relatively wider channels,which enhances the mass transfer at low-Reynolds-number.The generation,development and disappear of the vortex wave about oscillatory flow in an asymmetric channel was analyzed quantitatively and tested experimentally by using PIV(Particle Image Velocimetry).A series of velocity vector figures at different phases were obtained.The periodical characteristic of vortex wave flow is showed.The influence of Re number and St number on the vortex wave flow was analyzed,and time courses of the vortex core tracks and the vorticities distribution are presented.