对流项二次迎风插值格式在非结构化网格中的应用

在有限容积法的基础上发展了非结构化网格的对流项二次迎风插值（QUICK）格式．详细推导了扩散项采用格林函数法、对流项采用改进的QUICK格式的离散方程，对顶盖驱动流和圆柱绕流问题进行了计算，讨论了不同Re下计算的准确性和格式的收敛性，并与高精度结构化网格计算结果进行对比分析．结果表明，该格式的临界网格Peclet数为8／3左右，与中心差分相比较，该格式的计算精度与其相当，对流稳定性好，收敛速度高．同等条件下较结构化网格对复杂区域的模拟更接近实际测量结果，是一种对复杂区域计算有应用前景的对流格式．

Application of Quadratic Upwind Interpolation of Convective Kinematics Scheme in Unstructured Grids to Solve Navier-Stokes Equations

A new method to extend quadratic upwind interpolation of convective kinematics scheme(QUICK scheme) for the unstructured grid was developed based on the finite volume method.The discretization equations were deduced where the diffusion term and convection term apply the Green function method and QUICK scheme respectively.Two calculations were conducted for the flow in a Lid-driven square cavity and around a circular cylinder.The accurateness and convergence of unstructured grid difference scheme at different Reynolds number were discussed and a comparison was performed with the result of high order scheme in structured grid.The results show that although the developed method has a similar computational accuracy to the central difference scheme,its convection stability is better and convergence is faster than those of the central difference scheme.The critical grid Peclet number is about 8/3.In the complicated geometry the simulation result with the proposed unstructured grid method is closer to the measured data than that with the structured grid.