贴壁方柱湍流场TR-PIV实验研究  

TR-PIV measurement of the flow past a square cylinder flush-mounted on the wall

作　　者：万津津[1] 施鎏鎏[1] 余俊[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：《实验流体力学》2009年第2期31-35,共5页Journal of Experiments in Fluid Mechanics

基　　金：国家自然科学基金(50606024);NSFC-KOSEF基金(50711140398)资助项目

摘　　要：采用时变粒子图像速度场测试技术(TR-PIV),对低速循环水槽中贴壁二维方柱绕流湍流场进行了细致的测量。通过对实验得到的30000个连续瞬态速度场进行分析,得到了时均速度场和流线图谱,以及流向、法向速度分量的脉动强度场和涡量场。此外,对脉动速度时序信号进行谱分析,得到了流场中低频大尺度相干结构脱落频率。通过对瞬态速度场的分析,揭示了贴壁方柱绕流的旋涡脱落及其发展过程。The turbulent flow past a two-dimensional square cylinder flush-mounted on a plane wall was extensively measured by time-resolved particle image velocimetry （TR-PIV）.Toward this end, a low-speed recirculation water channel was established. Characteristics of the flow were statistically analyzed on 30,000 consecutive velocity maps in terms of time-averaged streamline pattern, velocity field, turbulence intensity and vorticity distributions. Existence of low - frequency coherent vortical structure embedded in the turbulent flow was revealed in terms of spectral analysis. The vortex shedding and development processes were described using the instantaneous velocity fields.

关 键 词：方柱 TR—PIV 分离流 再附湍流 相干结构 相关分析 

分 类 号：O357[理学—流体力学]