An Extrapolation Cascadic Multigrid Method for Elliptic Problems on Reentrant Domains

Autor: Dongdong He, Kejia Pan, Chuanmiao Chen
Rok vydání: 2017
Předmět:
Zdroj: Advances in Applied Mathematics and Mechanics. 9:1347-1363
ISSN: 2075-1354
2070-0733
DOI: 10.4208/aamm.oa-2016-0019
Popis: This paper proposes an extrapolation cascadic multigrid (EXCMG) method to solve elliptic problems in domains with reentrant corners. On a class of λ-graded meshes, we derive some new extrapolation formulas to construct a high-order approximation to the finite element solution on the next finer mesh using the numerical solutions on two-level of grids (current and previous grids). Then, this high-order approximation is used as the initial guess to reduce computational cost of the conjugate gradient method. Recursive application of this idea results in the EXCMG method proposed in this paper. Finally, numerical results for a crack problem and an L-shaped problem are presented to verify the efficiency and effectiveness of the proposed EXCMG method.
Databáze: OpenAIRE