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arXiv · 1901.05830

An AMG saddle point preconditioner with application to mixed Poisson problems on adaptive quad/cube meshes

Carsten Burstedde·Jose A. Fonseca·Bram Metsch
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Abstract

We investigate various block preconditioners for a low-order Raviart-Thomas discretization of the mixed Poisson problem on adaptive quadrilateral meshes. In addition to standard diagonal and Schur complement preconditioners, we present a dedicated AMG solver for saddle point problems (SPAMG). A key element is a stabilized prolongation operator that couples the flux and scalar components. Our numerical experiments in 2D and 3D show that the SPAMG preconditioner displays nearly mesh-independent iteration counts for adaptive meshes and heterogeneous coefficients.

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Carsten Burstedde, Jose A. Fonseca, Bram Metsch. 2019-01-17. An AMG saddle point preconditioner with application to mixed Poisson problems on adaptive quad/cube meshes. https://arxiv.org/abs/1901.05830

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