二阶方程Dirichlet边值问题混合元的超收敛

Superconvergence of Mixed Finite Element Methods for Second Order Equation with Dirichlet Boundary Value Problem

我们考虑二阶方程Dirichlet边值问题混合元的超收敛 .在正则矩形网格上 ,采用一阶Raviart-Thomas混合元空间 ,对有限元解经后处理后 ,其收敛于精确解的速度从二阶提高到四阶 .

For the 1-th Raviart Thomas finite element approximation of second order boundary value problem, the convergent rate can be increased from the second order to the fourth order by postprocessing superconvergence technique, if the underlying mesh is rectangular and regular.