非结构同位网格SIMPLE类算法收敛性能比较

以非结构网格的SIMPLE算法为基础,将算法扩展为SIMPLEC算法.利用30°角的斜方腔流动计算成果,分析了非结构同位网格的SIMPLE/SIMPLEC算法的收敛性能;比较了因网格的非正交而引入的非正交项的取舍对该算法收敛性能的影响;并采用显式校正步法对SIMPLEC算法进行了显式校正.比较表明,在非结构同位网格SIMPLEC算法中可忽略非正交项,但有必要对压力作亚松弛.显式校正步法可显著地加速在非结构网格上求解N-S方程的收敛性能,而且在不同的松弛因子组合下,均有较好的收敛速率.

Convergence performance of SIMPLE-like algorithm on unstructured grids

SIMPLEC algorithm was implemented on cell-centered, unstructured finite volume. By the case of skewed cavity flow with 30-degree angle, the convergence performance of SIMPLE/SIMPLEC algorithm was analyzed on unstructured grids and the influence of accepting or rejecting non-orthogonal terms was compared. If the under-relaxation is selected properly, SIMPLE/SIMPLEC has excellent performance. To simplify, non-orthogonal terms can be omitted. Then, explicit correction step was adopted to accelerate the convergence rate. It remarkably hastened the convergence rate of solving Navier-Stokes equation and good convergence can be obtained even if different sets of under-relaxation coefficient are selected.