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arXiv · 1502.04070

A robust multigrid method for the time-dependent Stokes problem

Stefan Takacs
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Abstract

In the present paper we propose a coupled multigrid method for generalized Stokes flow problems. Such problems occur as subproblems in implicit time-stepping approaches for time-dependent Stokes problems. The discretized Stokes system is a large-scale linear system whose condition number depends on the grid size of the spatial discretization and of the length of the time step. Recently, for this problem a coupled multigrid method has been proposed, where in each smoothing step a Poisson problem has to be solved (approximately) for the pressure field. In the present paper, we propose a coupled multigrid method where the solution of such sub-problems is not needed. We prove that the proposed method shows robust convergence behavior in the grid size of the spatial discretization and of the length of the time-step.

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Stefan Takacs. 2016-01-07. A robust multigrid method for the time-dependent Stokes problem. https://doi.org/10.1137/140969658

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