基于混合网格的三维Navier -Stokes方程并行算法

Parallel Computing Strategy for a 3D Hybrid Unstructured Navier-Stokes Solver

提出了一种基于混合网格的三维Navier Stokes方程的并行计算方法。Navier Stokes的求解采用了基于面的有限体积方法,该方法适用于任何网格类型。采用一方程Spalart Allmaras模型来计算紊流黏性。并行计算采用区域分裂的方法,利用METIS网格分区系统实现了各节点的加载平衡。节点间的数据交换通过调用MPI库函数来实现,采用非阻断通讯的方式来减少数据交换时间。充分利用FORTRAN90的动态存储特性来减少对内存的需求。最后,通过对绕DLR F6外形(翼身组合体+挂架+发动机短舱)黏性流动的数值模拟,验证了该并行程序的准确性,高性能并行计算以及处理复杂几何外形的能力。

A parallel computing strategy for a 3D hybrid unstructured Wavier Stokes solver has been developed. The Wavier-Stokes equations are solved by a face based finite volume method which is suitable for arbitrary mesh type. The Spalart Allmaras one-equation turbulence model is implemented to evaluate the turbulent viscosity. Parallel computation is based on the domain decomposition method and load balance is achieved by using METIS system. The Message Passing Interface （MPI） library routines are utilized to pass information between processors and non blocking communications are used to minimize the communications overhead. The dynamic allocation feature of FORTRAN 90 is fully exploited to reduce the memory requirement. Finally the parallel code is applied to simulation of viscous flow around the DLR-F6 geometry（wing-body-pylon-nacelle） to validate its accuracy, high parallel performance and the ability to deal with complex geometries.