On Dgs Relaxation: the Stokes Problem
نویسنده
چکیده
Multigrid methods have proven to be eecient methods for solving partial diier-ential equations (especially those of elliptic type). There is also growing experience with multigrid solvers for uids problems, e.g., the Stokes and Navier-Stokes equations (using both nite element and nite diierence discretizations). It is also well known that at the heart of any multigrid method is the smoother. In this work we look at a smoother introduced by Brandt and Dinar (DGS relaxation), we examine some of its properties and consider some possible modiications to it. It is well known that multigrid performance using DGS relaxation is sensitive to the treatment of boundaries; this issue is addressed.
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