壁湍流等动量区空间分布的实验研究  

Experimental investigation of the spatial distribution of uniform momentum zones in wall-bounded flow

作　　者：程肖岐 范子椰 唐湛棋 白建侠 姜楠[1,2] CHENG Xiaoqi;FAN Ziye;TANG Zhanqi;BAI Jianxia;JIANG Nan(School of Mechanical Engineering,Tianjin University,Tianjin 300354,China;Tianjin Key Laboratory of Modern Engineering Mechanics,Tianjin 300354,China;Department of Mathematics,Tianjin Renai College,Tianjin 301636,China)

机构地区：[1]天津大学机械工程学院,天津300354 [2]天津市现代工程力学重点实验室,天津300354 [3]天津仁爱学院数学教学部,天津301636

出　　处：《实验流体力学》2024年第4期21-28,共8页Journal of Experiments in Fluid Mechanics

基　　金：国家自然科学基金项目(11972251,11902218,12172242,12272265,12202310,12202309);中德合作研究小组基金项目(GZ1575);中国博士后基金项目(2022M712357)。

摘　　要：为深入探索湍流边界层等动量区的空间分布特性,使用大视场粒子图像测速仪在水洞中测量了平板湍流边界层流向–法向(x–y)平面内的速度矢量场。通过计算流向速度的概率密度函数,得到不同时刻和空间位置的等动量区分布,分析不同数量的等动量区沿流向的持续距离及出现频率。不同等动量区数量下,其对应的流向持续距离和流向间隔具有显著差异。当等动量区数量与其平均值相近时,等动量区在流向的持续距离较长,且流向间隔较小、出现频率较大;当等动量区数量与其平均值相差较大,其对应的流向持续距离较短,且流向间隔较大、出现频率较低。Experiments are carried out in a water tunnel to measure the velocity field in the streamwise-wall-normal plane by particle image velocimetry with a large field of view,in order to investigate the spatial distribution of the uniform momentum zones in the turbulent boundary layer.Through calculating the probability density function of the measured streamwise velocity,the temporal and spatial distribution of the uniform momentum zones are achieved.Then the lasting distance and the appearing frequency are analyzed for the uniform momentum zones with different numbers.For different uniform momentum zone numbers,there are apparent differences for both the corresponding lasting distance and appearing frequency.When the number of uniform momentum zones is close to their mean value,the uniform momentum zones can last for long distance along the streamwise direction and have small streamwise separation,appearing more frequently.On the contrary,when the number of uniform momentum zones is far from the mean value,the corresponding uniform momentum zones last for smaller distance along the streamwise direction and have a larger streamwise separation,appearing less frequently.

关 键 词：等动量区 湍流边界层 粒子图像测速 相干结构 空间分布 

分 类 号：O357.5[理学—流体力学]