非结构动网格在多介质流体数值模拟中的应用

采用非结构动网格方法对含多介质的流场进行数值模拟.采用改进的弹簧方法来处理由于边界运动而产生的网格变形.采用基于格心的有限体积方法求解守恒型的ALE(Arbitrary Lagrangiall-Eulerian)方程,控制面通量的计算采用HLLC(Hartem,Lax,van Leer,Contact)方法,采用几何构造的方法使空间达到二阶精度,时间离散采用四阶Runge-Kutta方法.物质界面的处理采用虚拟流体方法.本文对含动边界的激波管、水下爆炸等流场进行数值模拟,取得较好的结果,不同时刻界面的位置和整个扩张过程被准确模拟.

Application of unstructured moving grids in multi-material flow fluids simulation

Unstructured moving grids are used to simulate compressible multi-material flow fluids.Improved spring method is applied to handle grids' deformation because of their movement.The finite volume method based on cell-center scheme is adopted to solve the ALE(Arbitrary Lagrangian-Eulerian) formulation.The HLLC(Hartern,Lax,van Leer,Contact)method is presented to compute the flux of control face.The algorithm can achieve second-order precision in space by geometric construction method and forth-order in time by Runge-Kutta method.Material interface is treated by ghost fluid method.Problems of shock tube,underwater explosion are simulated and excited results are obtained.The locations of multimaterial interface at various times are calculated accurately and the propagating progress of multi-material interface is numerically simulated exactly.