SUPERCONVERGENCE OF LEAST-SQUARES MIXED FINITE ELEMENTS FOR ELLIPTIC PROBLEMS ON TRIANGULATION

SUPERCONVERGENCE OF LEAST-SQUARES MIXED FINITE ELEMENTS FOR ELLIPTIC PROBLEMS ON

TRIANGULATION

作者：陈艳萍;杨菊娥

作者机构：Institute for Computational and Applied

Mathematics,Xiangtan University,Xiangtan 411105,PRC;Institute for Computational and Applied Mathematics,Xiangtan University,Xiangtan 411105,PRC

来源：高等学校计算数学学报（英文版） ISSN：1004-8979 年：2003 卷：012 期：002 页码：214-225 页数：12 中图分类：O1 正文语种：chi

关键词：the least-squares mixed finite

element,superconvergence;lowest order,regular families of uniform triangulation,interpolation projection

摘要：In this paper,we present the least-squares mixed finite element method and investigate superconvergence phenomena for the second order elliptic boundary-value problems over triangulations.On the basis of the L2-projection and some mixed finite element projections,we obtain the superconvergence result of least-squares mixed finite

element solutions.This error estimate indicates an accuracy of O(h3/2)if the lowest order Raviart-Thomas elements are employed.