方柱绕流的大涡模拟

Numerical large eddy simulation of flow around square cylinder

采用大涡模拟(LES)方法对雷诺数为2.2×104的方柱绕流流场进行了数值模拟.使用非交错网格的有限差分法,分别对准三维物理模型和真实三维物理模型求解不可压N-S方程,将沿流向方向方柱水平中心线上的时均速度的计算结果与实验数据进行了比较,结果表明,三维模型的模拟结果优于准三维模型的模拟结果.比较升力系数和阻力系数发现,与二维模拟(RNG)方法相比, 三维模拟的结果更加接近实验测试数据.

Using the large eddy simulation (LES) technique, quasi three-dimensional (quasi 3D) and three-dimensional (3D) simulations of the velocity fields surrounding a rigid rectangular prism at the Reynolds number of 2.2×104 are conducted. A finite difference numerical scheme based on a staggered grid is employed. The convection terms and temporal marching are discretized with QUICK and Adams-Bashforth schemes, The computed mean velocity along the streamwise symmetry line and the drag and lift coefficients are compared with experimental results as well as numerical results of quasi three-dimensional and two-dimensional simulations (RNG k-ε). Three-dimensional (3D) simulation is in closer agreement with the experimental results than other reported numerical results.