摘要
1.引言
设Ω是多角形域,Γ0是边界Γ的角点集,三角剖分是均匀的.记m次有限元空间为Shm,u及v∈Shm可满足下列边界条件之一:
BV1.在Γ上,u=v=0;
BV2.对任何u,在Γ上v自由.
Based on an orthogonal expansion in a triangle, superconvergence for L2-projection to linear and quadratic triangular elements is studied. Assume that Ω is a polygonal domain, triangulation is uniform and Th is a set of all vertexes and side midpoints. Then, on Th, the average gradient D(u-uh)-O(h2) for linear element Uh, and u-uh = O(h4) for quadratic element uh. Under some boundary conditions, these properties upto the boundary are valid.
出处
《计算数学》
CSCD
北大核心
2003年第4期385-392,共8页
Mathematica Numerica Sinica
基金
国家重点基础研究计划(批准号19990328004)
国家自然科学基金(No.19331021)
