将龙格库塔间断有限元方法(RDDG)与自适应方法相结合,求解三维欧拉方程.区域剖分采用非结构四面体网格,依据数值解的变化采用自适应技术对网格进行局部加密或粗化,减少总体网格数目,提高计算效率.给出四种自适应策略并分析不同自适应策略的优缺点.数值算例表明方法的有效性.
We combine Runge-Kutta discontinuous finite element method(RKDG) with adaptive method to solve Euler equations.Domain is divided into unstructured tetrahedral meshes.Local mesh refinement technique is used.According to changes in numerical solution,mesh is refined or coarsened locally.Therefore,number of overall grids is reduced and computational efficiency is increased.We give four different adaptive strategies and analyze advantages and disadvantages.Finally,several examples validate the method.