基于LBM-LES的三维串列多圆柱绕流尾涡结构研究  

Research on wake structure of three-dimensional tandem multi-cylinder flow based on LBM-LES

作　　者：刘闯 黄剑峰 邵晨 LIU Chuang;HUANG Jianfeng;SHAO Chen(Water Conservancy College of Yunnan Agricultural University,650201 Kunming,China)

机构地区：[1]云南农业大学水利学院,昆明650201

出　　处：《应用力学学报》2022年第1期186-194,共9页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金资助项目(No.51541913);云南农业大学自然科学青年基金资助项目(No.2015ZR17)。

摘　　要：为了研究三维串联多圆柱绕流在不同圆柱间距比L/D(L为圆柱的间距,D为圆柱直径)情况下的尾涡结构,基于格子玻尔兹曼(LBM)方法,采用大涡模拟(LES)方法计算了高雷诺数下三维单圆柱及三维串联多圆柱在不同L/D情况下的尾涡流场。数值结果表明:LBM-LES方法可以较好地模拟出三维单圆柱以及串联多圆柱的尾涡结构;高雷诺数下单圆柱绕流尾迹变化具有不稳定性;串联多圆柱绕流存在临界间距比L/D=4,当圆柱间距比小于临界间距比时,圆柱间不会产生尾涡脱落;当圆柱间距比大于临界间距比时才会产生明显的涡脱落现象,且前方圆柱脱落的涡对后方圆柱有冲击作用,会对后方圆柱的升/阻力系数振动幅值有一定的影响;串联多圆柱绕流的上下游时均阻力系数曲线在临界间距比时会发生转折,呈逐渐增大趋势;当圆柱间距比小于临界间距比时,在下游圆柱前增加圆柱会对下游圆柱以及中游圆柱的时均阻力系数产生影响,而当圆柱间距比大于临界间距比时,在下游圆柱前增加圆柱对下游圆柱以及中游圆柱的时均阻力系数基本没有影响。In order to study the wake structure of three-dimensional tandem multi-cylinder flow at different L/D(L is the spacing between the cylinders and D is the diameter of the cylinder),based on the lattice Boltzmann method(LBM),the large eddy simulation(LES) method was used to calculate the wake flow field of three-dimensional single cylinder and three-dimensional series multi-cylinder under different L/D conditions.The results show that LBM-LES method can well simulate the wake structure of three-dimensional single cylinder and multi-cylinder in series.The wake change of single cylinder with high Reynolds number is unstable.There is a critical spacing ratio L/D=4.When the spacing ratio between cylinders is smaller than the critical spacing ratio,there is no vortex shedding between the cylinders.When the critical spacing ratio L/D is 4,the vortex shedding phenomenon is obvious,and the vortex falling off the front cylinder affects the rear cylinder,which will have a certain impact on the vibration amplitude of the lift and drag coefficients of the rear cylinder.When the ratio of cylinder spacing is smaller than the critical spacing ratio,the time average resistance coefficient curve of the upstream and the downstream of the flow around multiple cylinders in series will turn at the critical spacing ratio.When the boundary spacing ratio is 4,adding a cylinder in front of the downstream cylinder will affect the time average resistance coefficient of the downstream cylinder and the midstream cylinder.But when the cylinder spacing ratio is greater than the critical spacing ratio of 4,adding a cylinder in front of the downstream cylinder does not affect the time average resistance coefficient of the downstream cylinder or the middle cylinder.The research results have certain theoretical reference value for practical engineering.

关 键 词：格子玻尔兹曼方法 大涡模拟 圆柱绕流 尾涡结构 数值模拟 

分 类 号：O352[理学—流体力学]