无界区域上基于自然边界归化的一种重叠型区域分解法及其离散化

1．引言由于科学技术的迅猛发展，人们遇到许多大规模科学和工程计算问题．随着并行计算机的出现和应用，并行技术越来越得到人们的重视和研究．区域分解法成为并行计算和处理这类问题的主要方法之一．但是，对于无界区域上的椭圆边值问题，因进行区域分解后至少有一个区域仍为无界区域，故仅应用通常的区域分解算法求解是不够的．由于边界归化是处理无界区域问题的有效手段，通常采用边界元和有限元耦合的方法求解此类问题IZ，6。8。121．或片什适当的人工边界并在此边界上加近似边界条件，再在有限区域应用有限元方法求解【人习．近年来…

AN OVERLAPPING DOMAIN DECOMPOSITION METHOD BASED ON THE NATURAL BOUNDARY REDUCTION FOR UNBOUNDED DOMAINS AND ITS DISCRETIZATION

In this paper, based on the natural boundary reduction suggested by Feng and Yu, an overlapping domain decomposition method with its discretization is discussed. This method is very effective especially for problems over unbounded domains. The geometric convergency of both continuous and discrete problems is proved. The theoretical results as well as the numerical examples show that the convergence rate of this discrete Schwarz iteration is independent of the finite element mesh size, but dependent on the frequency of the exact solution and the overlapping degree of the subdomains.