A fast spectral element solver combining static condensation and multigrid techniques

We propose a spectral element multigrid method for the two-dimensional Helmholtz equation discretized on regular grids. Combining p-multigrid with static condensation the method achieves nearly linear complexity with an order-independent convergence rate for solving the condensed equations. For smoo...

Full description

Saved in:
Bibliographic Details
Published inJournal of computational physics Vol. 255; pp. 384 - 395
Main Authors Haupt, L., Stiller, J., Nagel, W.E.
Format Journal Article
LanguageEnglish
Published Elsevier Inc 15.12.2013
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:We propose a spectral element multigrid method for the two-dimensional Helmholtz equation discretized on regular grids. Combining p-multigrid with static condensation the method achieves nearly linear complexity with an order-independent convergence rate for solving the condensed equations. For smoothing we consider two groups of edge-based relaxation schemes, the best of which attains a multigrid convergence rate of ρ≈0.014 to 0.028. Numerical experiments have been carried out that demonstrate the robustness of the approach for orders up to 32 and a total of 109 degrees of freedom. In comparison with a fast finite difference solver, the latter is clearly outperformed already for errors of one percent or lower.
Bibliography:ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ISSN:0021-9991
1090-2716
DOI:10.1016/j.jcp.2013.07.035