SUPERCONVERGENCE ANALYSIS OF LOW ORDER NONCONFORMING MIXED FINITE ELEMENT METHODS FOR TIME-DEPENDENT NAVIER-STOKES EQUATIONS  

作　　者：Huaijun Yang Dongyang Shi Qian Liu 

机构地区：[1]School of Mathematics,Zhengzhou University of Aeronautics,Zhengzhou 450046,China [2]School of Mathematics and Statistics,Zhengzhou University,Zhengzhou 450001,China

出　　处：《Journal of Computational Mathematics》2021年第1期63-80,共18页计算数学（英文）

基　　金：This work is supported by National Natural Science Foundation of China(Nos.11671369,11271340).

摘　　要：In this paper,the superconvergence properties of the time-dependent Navier-Stokes equations are investigated by a low order nonconforming mixed finite element method(MFEM).In terms of the integral identity technique,the superclose error estimates for both the velocity in broken H-norm and the pressure in L2-norm are first obtained,which play a key role to bound the numerical solution in Lx-norm.Then the corresponding global superconvergence results are derived through a suitable interpolation postprocessing approach.Finally,some numerical results are provided to demonstrated the theoretical analysis.

关 键 词：Navier-Stokes equations Nonconforming MFEM Supercloseness and super-convergence. 

分 类 号：O17[理学—数学]