数学物理学报 ›› 2013, Vol. 33 ›› Issue (4): 735-745.

• 论文 • 上一篇    下一篇

带有阻尼项的定常Stokes方程的低阶非协调混合有限元方法的超逼近和超收敛分析

石东洋1|于志云2   

  1. 1.郑州大学数学系 郑州 450001|2.中原工学院理学院 郑州 450007
  • 收稿日期:2011-05-30 修回日期:2012-12-12 出版日期:2013-08-25 发布日期:2013-08-25
  • 基金资助:

    国家自然科学基金(10671184, 10971203, 11271340)、高等学校博士学科点专项科研基金(20094101110006)、国家青年基金(11101384)和河南省基础与前沿技术研究计划项目(122300410208)资助

Superclose and Superconvergence Analysis of a Low Order Nonconforming Mixed Finite Element Method for Stationary 
Stokes Equations with Damping

 SHI Dong-Yang1, YU Zhi-Yun2   

  1. 1.Department of Mathematics, Zhengzhou University, Zhengzhou 450001;
    2.College of Science, Zhongyuan University of Technology, Zhengzhou 450007
  • Received:2011-05-30 Revised:2012-12-12 Online:2013-08-25 Published:2013-08-25

摘要:

用带约束的非协调旋转Q1 元和分片常数元来逼近定常的、不可压带有阻尼项的Stokes方程的速度和压力. 证明了逼近解的存在惟一性. 再利用精确解和逼近解的先验估计, 并恰当选择参数ανr, 得到了最优误差估计及超逼近结果. 最后, 通过插值后处理技术, 导出了速度的H1 -模和压力 L2 -模的O(h2)阶的整体超收敛.

关键词: Stokes方程, 阻尼项, 非协调混合元, 超逼近和超收敛, 最优误差估计

Abstract:

In this paper, we apply the constrained nonconforming rotated Q1 element and the piecewise constant element to approximate the velocity and the pressure for the stationary、impressible Stokes equations with damped term, respectively. The existence and uniqueness of the approximated solutions are proved. Employing the prior estimates of the exact and approximate solutions and choosing the appropriate parameters α, ν and r, the optimal error estimates and the superclose results are derived. Finally, the O(h2) order global superconvergence in H1-norm for the velocity and L2-norm for the pressure is obtained by use of a postprocessing technique.

Key words: Stokes equations, Damped term, Nonconforming mixed elements,  Superclose and superconvergence,  Optimal error estimates

中图分类号: 

  • 65N30