Lagrange方法基于保正性的时间步长

Positivity Preserving Time Step for Lagrange Method

对交错网格上Lagrange预估-校正显示格式的时间步长选取提出新的方法.与经典CFL稳定性理论时间步长选取方法不同,新方法考虑了原始微分方程组的非线性效应,并基于物理量保正性给出了自适应的时间步长选取方法.数值实验验证了该方法有效.

We propose a method of time step for predicator-corrector scheme of Lagrangian method on stagger grids. It is different from CFL time step based on tradional stable theory. The method considers nonlinear effect of original partial differential equations, and gives an adaptive time step based on physical quantities positivity preserving. Numerical results confirm validity of the method.