无限域波动问题的局部非协调网格法

Local incompatible mesh method for infinite media wave problems

基于远置人工边界的原理采用了局部非协调网格法,即以协调点集的位移、速度、加速度变量作为基本变量,非协调点集的变量作为从变量,通过线性插值建立从变量与基本变量之间的线性关系,从而导出以基本变量作为未知量的总体线性方程组。并通过算例验证了本文方法的精度。本文方法不仅大大减少了计算量,提高了求解效率,而且避开了大角度入射和人工边界稳定性的问题,还可以用于其他人工边界的检验工作。

There are still the problems concerning boundary stability and large angle incidence in the common methods of ellminating the reflection of artificial boundary. Basing on the principle of remote artificial boundary, the present paper adopts the method of local incompatible mesh. In this method, the displacement, velocity and acceleration of compatible point set are used as basic variables, and the same variables of incompatible point set are used as subordinate variables, then the linear re- lationship between basic variables and subordinate variables is establlshed by linear interpolation, and the global linear equa- tions composed of basic variables are derived. The precision of the method advised by this paper is verified by a calculation ex- ample. This method can not only decrease the calculation quantity but also improve the solving efficiency, and furthermore the problems of boundary stability and large angle incidence are avoided, so it can be used to check other kinds of artificial boundary.