沙纹床面涡量特性实验研究

沙纹的形成与水流流态密切相关，但对于其相互关系至今尚无确定的结论。采用PIV（Particle Image Velocimetry）测量设备对沙纹床面水流特性及涡量特性进行了实验研究。通过对平床与沙纹床面涡量场的比较，得到了沙纹床面的涡量分布区域。结果表明，涡量较大值主要集中在沙纹的背水坡面与迎水坡带，之外区域涡量值约为零。结论对研究沙纹的形成有积极意义。

Experimental study of vortex characteristics of sand ripple bed

The generation of sand ripple is closely related to the flow pattern, and the relation between sand ripple and flow condition is still not clear. The Particle Image Velocimetry (PIV) was used to study the flow and vortex characteristics on the ripple bed. The vortex field on ripple bed were compared with that of the flat bed. The results show that the large vortex area was concentrated on the upstream and downstream slope of the ripple while the vortex values in other areas are nearly zero. The results were helpful for the study of sand ripple generation.