壁湍流SL标度律相关参数的实验分析  

Experimental Analysis of Relevant Parameters of SL Scaling Law in Wall Turbulent Flow

作　　者：张珂[1] 

机构地区：[1]安徽广播电视大学城建学院,安徽合肥230001

出　　处：《成都大学学报（自然科学版）》2015年第3期302-306,共5页Journal of Chengdu University（Natural Science Edition）

摘　　要：标度律是研究湍流统计和湍流级串的重要工具,应用PIV系统的分辨率较高和帧率较高的特点,对在动量损失厚度雷诺数Reθ=2 694时,实验区域的脉动速度数值进行测量,利用统计学和小波分析的方法对SL标度律的间歇参数和最奇异标度指数进行拟合分析.结果显示:SL标度律的间歇参数并不是一个固定的数值,而是和尺度的大小及壁面位置有关;SL标度律的另一个参数最奇异标度指数是随着壁面距离和尺度的增大趋于稳定,在大尺度上与壁面的距离无关.The scaling law is of great importance in the research on statistics of turbulence and turbulence cascade. In the thesis, PIV system which is characterized by higher resolution and frame rate, is used to measure the fluctuating velocity in the experimental region when the momentum loss thickness, Ree = 2 694. The method of wavelet analysis and statistics are used in this paper to do fitting analysis of the SL sealing law, the intermittence parameters and the exponent of the most intermittent structure. The results show that the intermittence factor of the SL scaling law is not a fixed value, but it is related to the scale size and the different distances from the wall. However, the exponent of the most intermittent structure is another parameter of SL scaling law, so it tends to be more stable with the increase of the distance from wall and the enhancement of the scale. When the scale is big enough, the exponent of the most intermittent structure is not related to the distances from the wall.

关 键 词：标度律 最奇异标度指数 间歇参数 湍流边界层 

分 类 号：O357.54[理学—流体力学]