具有微型沟槽结构旋转圆盘减阻的实验研究

建立了开式旋转圆盘系统减阻实验平台,对圆盘螺线沟槽减阻进行实验研究,并可以结合数值研究手段对微型沟槽减阻的机理进行研究。实验结果表明圆盘开槽面积为7.4%时,螺线微型沟槽使得旋转圆盘的最大减阻率达6.1%,V型沟槽两侧的压力差所产生的正扭矩是其减阻的主要原因。沟槽还能起到提高圆盘内径与外径处的静压差的效果。研究结果还表明,采用和平板减阻相同的无量纲尺寸的沟槽会引起圆盘表面的剪应力较大增加。

Experimental Investigation of Drag Reduction for Rotating Disk Surface With Spiral Grooves

An experimental platform for drag reduction of open rotating disk system has been constructed.Combined with the numerical study,the drag reduction effects of spiral grooves on rotating disk and the drag reduction mechanism of grooves have been investigated in detail.The results show that the maximum drag reduction ratio of 6.1%is obtained on rotating disk with the 7.4%disk surface area machined with spiral grooves.The main drag reduction mechanism in this experiment is that the pressure difference of the two sides in V-shaped groove creates a positive torque.Furthermore,the grooves have an effect of increasing the pressure difference between the inner and outer radius of rotating disk.Even though the grooves on the surface of disk have the same dimensionless height and width with that of the grooves on the surface of flat plate where drag reduction occurs,it increases significantly the shear stress on disk surface.