摘要
为研究高雷诺数为22 000下方柱周围流场形态及气动力特性,基于开源计算流体动力学(computational fluid dynamic,CFD)软件Open Foam平台,采用基于动态亚格子模型的大涡模拟(large eddy simulation,LES)方法,对均匀来流作用下的方柱绕流进行了三维数值模拟.首先,通过对基于时间积分的平均积分分量的比较,验证了本数值计算的准确性;其次,深入分析了方柱周围及其尾流区的流场结构,给出了流场结构的平均和湍流特征,并在此基础上,研究了其气动力特性;最后,分析了两种长径比下表面压力的展向空间相关性.研究结果表明:雷诺数为22 000下方柱尾流区回转长度为1.37倍方柱宽度,Strouhal数为0.121,脉动升力系数为1.40;展向长度取8倍方柱宽度可更准确地获得周围湍流特性.
Three-dimensional large eddy simulations（ LES） were performed at high Reynolds numbers（ Re = 22 000） and using the dynamic Smagorinsky sub-grid model to investigate uniform flow over a square cylinder. Meshing of the model was performed using Open Foam-an open-source computational tool. Mean integral quantities were compared against existing experimental and numerical results to validate the proposed numerical method. Subsequently,the flow structure around and aerodynamic forces acting on the cylinder were analysed to perform an in-depth investigation of mean-and turbulentflow characteristics. Lastly,the influence of the grid system around the cylinder and span-wise length on the flow structure and spatial correlation were investigated via comparison between different cases.Results demonstrate that the recirculation length in the wake approximately measured 1. 37 D（ width of square）,while the Strouhal number and RMS value of the lift coefficient are 0. 121 and 1. 40,respectively. In addition,domain length along the span-wise should be equal to 8 D in order to obtain clear turbulent-flow characteristics.
作者
周强
廖海黎
曹曙阳
ZHOU Qiang;LIAO Haili;CAO Shuyang(Key Laboratory of Wind Engineering of Sichuan Province, Southwest Jiaotong University,Chengdu 610031, China;State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)
出处
《西南交通大学学报》
EI
CSCD
北大核心
2018年第3期533-539,共7页
Journal of Southwest Jiaotong University
基金
国家自然科学基金资助项目(51378442
51708462)
中央高校基本科研业务费专项资金资助项目(2682016CX006)
关键词
方柱绕流
大涡模拟
流场特性
尾流结构
空间相关性
flow over square cylinder
large eddy simulation
flow characteristics
wake structures
spatial correlation
