涡旋脉动的流体可视化和粒子成像测速(PIV)分析

This article treats of the flow motion over the so-called vortex ripples which
are generated by water oscillations above a sand bed. We focus mainly our experimental
works on the morphology and the dynamics of transient flow patterns above real vortex
ripples. With the help of flow visualizations and Particle Image Velocimetry measurements
with a high-speed video CCD camera, we test numerical simulations, which predict the
existence of a secondary vortex with a streamlines representation. However, our
experimental findings show only one vortical structure and validate the observations of
Bagnold in 1946 (using real ripples but with no visualization and measurement) and Sand
Andersen & al. in 2004 (using model ripples) with respect to the existence of a transient jet. 德国LaVision PIV/PLIF粒子成像测速场仪 HighSpeedStar PIV相机 用于粒子成像测速(PIV)的荧光示踪粒子