二阶迎风有限体积法方腔流数值模拟

介绍了一种基于非结构网格的二阶迎风有限体积离散格式，在对流项的离散过程中，为了达到二阶精度，在界面上对物理量咖作Taylor展开，在处理展开项中的梯度时经入NND格式的优点，克服了中心差分格式不稳定的缺点，并对方腔流动进行了系统的数值模拟．计算网格采用三角形网格，节点数为12960，单元数为25600．压强修正基于SIMPLEC方法．给出了雷诺数Re达到5000时的定常流动结果，与以往方腔流计算的标准解非常吻合，但所用的网格数要少．计算结果表明该二阶迎风有限体积算法有很好的收敛性和稳定性，且松弛因子对计算结果影响很小．

Numerical Simulation of Square Cavity Flow by Second-order Up-wind Finite Volume Method

A discretization scheme based on unstructured grids and the Finite Volume Method(FVM) with secondary-order accuracy was investigated in this paper.In order to achieve secondary-order accuracy,Taylor's formula was used on the interface for the convection term.NND(Non-oscillatory,containing No free parameters and Dissipative scheme) was employed to cope with the gradient term in Taylor's formula to avoid the instability of the center difference scheme.The Delaunay triangle grids were employed and the square cavity flow was systematically simulated.The nodes and the elements number were 12960 and 25600 respectively.The Semi-Implicit Method for the Pressure-Linked Equations Consistent(SIMPLEC) method was used on pressure correction.The steady flow numerical simulation results with Reynolds number up to 5000 were given in good agreement with the benchmark solution.The less grid number was used in this paper.The present method has good convergence and stability and furthermore,the relaxation factor has little effect on the results.