使用基于SA(Spalart-Allmaras)湍流模型的分离涡模拟(DES,Detached-Eddy Simulation)方法,对圆柱绕流和超声速圆柱底部流动等高雷诺数大分离流动进行了数值模拟.无粘通量的计算采用二阶迎风格式,时间推进使用二阶隐式双时间步法.计算表明相对于雷诺平均N-S方程(RANS,Reynolds-Averaged Navier-Stokes)模拟,时空均为二阶精度的DES模拟能够分辨更为精细的分离区三维旋涡结构,对分离区主要湍流结构的捕捉和平均压力分布的预测取得了满意的结果.
The numerical simulation of the high Reynolds number,massively separated flows such as flow over the circular cylinder and supersonic base flow were performed with detached-eddy simulation based on Spalart-Allmaras turbulence model.The inviscid flux was obtained with 2nd order upwind scheme and 2nd order implicit dual time method was used for accurate time marching.Detached eddy simulation presented more resolved three dimensional turbulent vortex structures compared with corresponding RANS(Reynolds-averaged Navier-Stokes) method.The resolution of main turbulent structures in wake region and prediction of mean pressure distribution show agreement with experiments.