基于非结构动网格的非定常气动力计算

对用于非结构动网格生成的弹簧近似方法进行了研究。通过采用顶点弹簧方法,分析研究了弹簧倔强系数的取值,同时通过引入挤压倔强系数和边界修正,对标准弹簧近似方法进行了改进。改进后的方法可以大大提高网格变形能力和网格质量。应用本文发展的非结构动网格生成方法耦合求解基于Arbitrary Lagrangian-Eulerian(ALE)描述的欧拉方程,计算了谐和振动NACA0012翼型及矩形机翼的跨声速非定常气动力,计算结果与参考文献提供的结果及实验结果吻合良好。

Calculation of Unsteady Flow Using Dynamic Unstructured Grids

In this paper, a spring analogy method for dynamic unstructured grid generation was studied, The stiffness of springs in the modified vertex spring analogy was analysed. Squashing stiffness and boundray correction were introducted for the modification to the standard spring analogy method. The application of the modified spring analogy method to a 3D grid generation showed that the deformation capability and quality of the grids are greatly improved. Coupled with the 3D ALE Euler solver, this dynamic unstructured grid method was used to simulate unsteady transonic flow about an oscillating NACA0012 airfoil and rectangular wing. The computational results are in good agreement with those from other literatures.