V型沟槽减阻的实验研究

Experiment Study on V-groove Drag Reduction

为了研究不同形状沟槽的阻力特性,利用PIV技术对零压力梯度下的V形和光滑平板湍流边界层进行对比测量。考察了在相同的来流速度下同一位置的平均速度分布、壁面切应力,并利用动量损失法计算得到了沟槽板和光滑平板局部阻力系数。分析结果表明:V形沟槽能增加黏性底层的厚度,减小壁面切应力,有减阻效果。

In order to research the resistance characteristic of different shapes of grooves, PIV technology is used to meansure the turbulent boundary layer of a V-shaped and smooth plate at a zero pressure gradient and compare the results and inspect the average velocity distribution and the wall shear stress at the same location and the same flow rate. The local drag coeeficients of both the grooves and the smooth plate are calculated by using the momentum loss method. The results indicate that grooves can incrcase the thickenss of a viscous sub-layers but decrease the wall shear stress, showing an obvious effect of drag reduction.