通过对由经典加罚算法得到的两个解进行线性组合,研究Stokes方程低阶非协调混合元的改进加罚算法.该方法利用较大的罚参数能得到同使用较小参数的经典加罚方法一样的收敛阶.此外,基于单元的特性和插值后处理技巧。得到一些超收敛结果.从而改进以往的文献结果.
By a linear combination of two solutions gained by classical penalty finite element method for Stokes equations, a modified penalty scheme of low order nonconforming mixed finite elements is studied. It is shown that this method with a larger penalty parameter can achieve the same accuracy as the classical method with a smaller one. Furthermore,based on some special properties of the low order elements and the postprocessing technique,some superconvergence results are derived,which improve the results of previous literature.