亚临界雷诺数下串列三圆柱体绕流特性研究  

Study on flow characteristics of three tandem circular cylinders at a subcritical Reynolds number

作　　者：涂佳黄[1,2] 王程 梁经群 邓旭辉 郭小刚[1,2] 张平 TU Jia-huang;WANG Cheng;LIANG Jing-qun;DENG Xu-hui;GUO Xiao-gang;ZHANG Ping(College of Civil Engineering and Mechanics,Xiangtan University,Xiangtan 411105,China;Hunan Key Laboratory of Geomechanics and Engineering Safety,Xiangtan 411105,China;Yongzhou Lingling Financial Investment Assessment Center,Yongzhou 425100,China)

机构地区：[1]湘潭大学土木工程与力学学院,湖南湘潭411105 [2]岩土力学与工程安全湖南省重点实验室,湖南湘潭411105 [3]永州市零陵区财政投资评审中心,湖南永州425100

出　　处：《船舶力学》2021年第9期1159-1171,共13页Journal of Ship Mechanics

基　　金：国家自然科学基金项目(51434002,11602214);湖南省自然科学基金项目(2020JJ4568);湖南省教育厅科学研究优秀青年项目(18B079);中国博士后科学基金资助项目(2017M622593)。

摘　　要：基于流体计算软件Fluent,本文采用Smagorinsky亚格子模型的大涡模拟(LES)方法,对Re=3900时串列三圆柱体群绕流进行了三维数值模拟。首先,通过求解单圆柱算例来验证计算模型及参数的正确性。然后,分析了间距比对三圆柱体群绕流特性的影响。数值结果表明:随着间距比的增大,剪切层会出现再附着、卷起再附着和无再附着三种形式,同时尾涡第一次卷起位置也会逐渐向上游移动。此外,圆柱体尾流区顺流向时均速度分布由“U”型变为“V”型,横流向时均速度近尾流区分布呈反对称,远尾流区反对称现象会逐渐减弱。在L/D=4.1~4.2范围内,串列三圆柱体群所受的流体力会发生突变。上中游圆柱体平均阻力系数会增大,与双圆柱体工况类似;然而,下游圆柱体会减小。最后,三圆柱体的升力系数主频率值基本一致,并随着间距比的增大而增大。Based on Fluent,three-dimensional numerical simulation for the three circular cylinders in tandem at Re=3900 was carried out by using the large eddy simulation(LES)method of Smagorinsky sub-grid model in this paper.Firstly,the accuracy of the model and parameters was verified by solving a single cylinder.Then,the influence of spacing ratio on the flow characteristics of three circular cylinder groups was analyzed.The numerical results show that three forms of shear layer are observed,such as reattachment,roll reattachment and without reattachment with the increase of spacing ratio.Meanwhile,the first roll position of wake vortex also gradually moves upstream.On the other hand,the shape of the average velocity distribution in the inline direction in the cylinder wake region changes from"U"to"V".However,in the cross flow direction,the average velocity distribution is anti-symmetric in the near wake region,and the anti-symmetric feature weakens in the far wake region.The fluid forces of the three circular cylinders in tandem are mutated in the range of L/D=4.1~4.2.And the average drag coefficients of the upstream and midstream circular cylinders increase at L/D=4.2,which is similar to the two circular cylinders in tandem.However,the average drag coefficient of the downstream circular cylinder decreases.Finally,the primary frequencies of lift coefficient of the three tandem circular cylinders are basically the same,and increase with the increase of spacing ratio.

关 键 词：亚临界雷诺数 串列三圆柱 间距比 流体力 尾流特性 

分 类 号：O357.1[理学—流体力学]