近壁方柱绕流非定常特性的TR-PIV测量  

TR-PIV MEASUREMENTS OF THE UNSTEADY CHARACTERISTICS OF THE FLOW PAST A SQUARE CYLINDER NEAR THE WALL

作　　者：施鎏鎏[1] 余俊[1] 万津津[1] 刘应征[1] 

机构地区：[1]上海交通大学动力机械与工程教育部重点实验室,上海200240

出　　处：《工程热物理学报》2009年第8期1312-1314,共3页Journal of Engineering Thermophysics

基　　金：自然科学基金项目(No.50606024);NSFC-KOSEF基金资助项目(No.50711140398)

摘　　要：本文采用时变粒子图像速度场测试技术(TR-PIV),研究了低速循环水槽中近壁(G/D=0.1)二维方柱绕流的非定常流动特性。通过对实验得到的20000个连续瞬态速度场进行分析,得到了时均速度矢量场,速度大小分布和流向速度脉动强度分布。根据回流间歇系数的分布确定了时均再附点的位置。通过对原始速度场进行互相关分析,得到了流场中低频大尺度相干结构输运速度U_c=0.4U_0。The unsteady characteristics of the flow past a two-dimensional square cylinder near the wall （G/D=O. 1） was investigated by time-resolved particle image velocimetry （TR-PIV） in a low-speed water channel. Time-averaged vector field, velocity contour, and streamwise velocity fluctuations were obtained by ensemble of 20000 sequential velocity fields. The time-averaged reattachment point was determined according to the distribution of reverse flow intermittency near the wall and the convection speed of the large scale structures was determined to be Uc = 0.4U0 by cross-correlation calculation of the velocity fields.

关 键 词：TR-PⅣ 相干结构 互相关 

分 类 号：TB126[理学—工程力学]