数学物理学报 ›› 2016, Vol. 36 ›› Issue (4): 656-671.

• 论文 • 上一篇    下一篇

非线性四阶双曲方程低阶混合元方法的超收敛分析

张厚超1, 石东洋2   

  1. 1. 平顶山学院数学与统计学院 河南平顶山 467000;
    2. 郑州大学数学与统计学院 郑州 450001
  • 收稿日期:2015-12-13 修回日期:2016-05-25 出版日期:2016-08-26 发布日期:2016-08-26
  • 作者简介:张厚超,zhc0375@126.com
  • 基金资助:

    国家自然科学基金(11271340)和河南省科技计划项目(162300410082)资助

Superconvergence Analysis of a Lower Order Mixed Finite Element Method for Nonlinear Fourth-Order Hyperbolic Equation

Zhang Houchao1, Shi Dongyang2   

  1. 1. School of Mathematics and Statistics, Pingdingshan University, Henan Pingdingshan 467000;
    2. School of Mathematics and Statistics, Zhengzhou University, Zhengzhou 450001
  • Received:2015-12-13 Revised:2016-05-25 Online:2016-08-26 Published:2016-08-26
  • Supported by:

    Supported by the NSFC(11271340)and the Science and Technology Planning Foundation of Henan Province(162300410082)

摘要:

对一类非线性四阶双曲方程利用双线性元Q11Q01×Q10元给出了一个低阶混合元格式. 基于上述两个单元的高精度结果,采用插值和投影相结合的方法,利用对时间t的导数转移技巧,借助插值后处理技术,在半离散格式下导出了原始变量u和中间变量v=-ΔuH1模意义下及流量=-▽u在(L22模意义下具有Oh2)阶的超逼近和超收敛结果. 与此同时,在全离散格式下,证明了uvH1模意义下及???20160405-1???在(L22模意义下单独利用插值或投影所无法得到的具有Oh2+(Δt2)阶的超逼近和超收敛结果.

关键词: 非线性四阶双曲方程, 混合元方法, 半离散和全离散格式, 超逼近和超收敛

Abstract:

Based on the bilinear element Q11 and the Q01×Q10 element, a lower order conforming mixed finite element approximation scheme is proposed for nonlinear fourth-order hyperbolic equation. With the help of the known high accuracy results of the about two elements, by use of derivative delivery techniques and the post-processing technique, the superclose and superconvergence with order O(h2) for both scalar original variable u and the intermediate variable v=-Δu in H1 norm and the flux =-▽u in (L2)2 norm are derived in semi-discrete schemes through interpolation and Ritz projection approach, respectively. Meanwhile, the superclose and superconvergence with order O(h2+(Δt)2) for both u and v in HM1 norm and ???20160405-1??? in (L2)2 norm are proved in fully-discrete schemes, which cannot be deduced by the interpolation and Ritz projection alone.

Key words: Nonlinear fourth-order hyperbolic equation, Mixed finite element method, Semi-discrete and fully-discrete schemes, Superclose and superconvergence

中图分类号: 

  • O242.21