厚壁面湍流边界层对圆柱脱涡影响的实验研究

Effect of Thick Wall Turbulent Boundary Layer to Vortex Shedding of Circular Cylinder

在风洞中,用热线风速仪和压力传感器进行嵌入湍流边界层内的圆柱脱涡实验研究.测量了尾涡脱落频率和平板表面压强脉动,目的是分析当圆柱嵌入空气湍流边界层的情况下,间隙比值对尾涡脱落频率及壁脉动压强的影响.实验结果得到了尾涡无量纲频率S t随间隙比及雷诺数的变化情况,壁脉动压强周期性成分的变化规律,还得到了在一定雷诺数下,圆柱对边界层速度的影响范围,为今后的工作和研究提供了实验依据.

Labview and hot film anemoscope ware employed to study the fluid flow around a circular cylinder which bed in the turbulent boundary layer in the wind tunnel.The vortex shedding frequency and the wall pressure fluctuations were measured with the aim of analying the effect of changing the clearance ratio shedding and the wall pressure fluctuations when the circular cylinder bed in the air turbulent boundary layer.The regularities of the dimensionless frequency of the wake vortex St are gained and varied as the clearance ratio and the Reynolds number changed,and the variable regularities of the periodicity component of the wall pressure fluctuations.Also the effect scope of wake to the air turbulent boundary layer in a certain Reynolds number.Those will be the guidance for further study.