A SIMPLIFIED AND STABILIZED SECOND ORDER MIXED FINITE ELEMENT FORMULATION BASED ON BUBBLE FUNCTIONS FOR SECOND-ORDER ELLIPTIC EQUATIONS
二阶椭圆问题基于泡函数的简化的稳定化二阶混合有限元格式

In this paper, a stabilized second order mixed finite element formulation based on bubble functions for second--order elliptic equations is studied, and a simplified second order mixed finite element formulation with less freedom degrees is obtained by eliminating all bubble functions. It is shown by analyzing error that the convergence of the simplified and stabilized second order mixed finite element formulation eliminated all bubble functions is the same as that of the stabilized second order mixed finite element formulation with bubble functions, but it can save 6Np freedom degrees (where Np is the number of vertices of triangularization).