串列双圆柱时均流场特性分析  

Characteristic of the Mean Wake Field of Two Tandem Circular Cylinders

作　　者：邵山 陈少松[1] 魏恺 徐一航 SHAO Shan;CHEN Shao-song;WEI Kai;XU Yi-hang(School of Energy and Power Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]南京理工大学能源与动力工程学院,江苏南京210094

出　　处：《气体物理》2021年第5期62-66,共5页Physics of Gases

摘　　要：对Re=12000,间距比L/D=1.167,2.333,3.500和4.667的串列双圆柱后方速度场进行了实验测量,分析串列双圆柱后方不同剖面处的速度分布规律和湍流度分布规律.并通过流函数理论模型对小间距比串列双圆柱后方流场进行了分析,得出如下结论:与单圆柱相比,当串列双圆柱间距比较小时,后方圆柱的自由剪切层明显向内偏移.随着间距比的变大,由于前方圆柱的尾流对后方圆柱的干扰,后方圆柱的自由剪切层变得越来越模糊.对于间距比较大的串列双圆柱,其对后方流场的扰动较强,致使后方流场湍流强度和最大速度衰减量较大.通过流函数理论模型分析发现,在小间距比条件下,串列双圆柱由于两个圆柱的相互干扰,使得圆柱后方涡相互靠近,并且后方涡向外倾斜的角度也减小,从而导致了自由剪切层向内侧偏移.The velocity fields behind the tandem double cylinders with Re=12000 and spacing ratios L/D=1.167,2.333,3.500 and 4.667 were measured experimentally.The velocity distribution and turbulivity distribution at different sections behind the tandem double cylinders were analyzed.The flow field behind the tandem cylinders with small spacing ratio was analyzed by the stream function theory model,and the following conclusion was drawn:compared with the single cylinder,when the space between the tandem cylinders is small,the free shear layer of the rear cylinder is obviously shifted inward.As the spacing ratio increases,the free shear layer of the rear cylinder becomes more and more blurred due to the interference of the wake of the front cylinder to the rear cylinder.For the tandem cylinders with large spacing ratio,the disturbance to the rear flow field is strong,which leads to large turbulence intensity and maximum velocity attenuation in the rear flow field.Through the analysis of stream function theory model,it is found that under the condition of small spacing ratio,due to the mutual interference of two cylinders,the rear vortices of two cylinders are close to each other,and the angle of the rear vortices is reduced,which leads to the deviation of the free shear layer to the inside.

关 键 词：风洞实验 串列双圆柱绕流 流函数理论 自由剪切层 时均流场 

分 类 号：O357.5[理学—流体力学]