结合传统ALE方法和欧拉方法的优点,提出了整体ALE计算(GALE)的构想,通过整体重分重映使得ALE计算不再受限于物质界面的变形.当界面变形不大时,网格线与界面重合,以拉氏模式清晰地追踪物质界面;当界面有较大变形时,引入混合网格,采用欧拉方法捕捉界面.应用整体ALE方法数值模拟了气液激波管和分层Richtmyer-Meshkov(RM)不稳定性问题,取得了与理论解较为吻合的结果.
A new arbitrary Lagrangian-Eulerian method,global ALE method(GALE),is developed for compressible multimaterial flows with large deformation of interface.Unlike traditional ALE methods,where rezoning and remapping are performed only in the internal of one material region,and material interfaces are tracked by Lagrangian mesh lines,the GALE method attempts a compromise by combining the merits of both ALE and Eulerian methods by global remeshing and remapping.In the GALE method,modern Eulerian methods,such as mass fraction model,level set method,are coupled with a Godunov-type ALE method.Some benchmark problems,such as gas-liquid shock tube problem and stratified Richtmyer-Meshkov instability,were computed by the GALE to verify the method,and the numerical results agree well with exact solution or theoretical model.