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DOE OSTI · 1840118

Discretization-Accuracy Convergence for Full Algebraic Multigrid

Falgout, Robert D.·Manteuffel, Thomas A.·McCormick, Stephen F.·Mitchell, Wayne B.
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Abstract

Full multigrid (FMG) is well known for converging to the level of discretization accuracy in a single cycle for a wide class of partial differential equations when the multigrid hierarchy is derived from problem geometry. When applying an FMG cycle to a hierarchy generated by algebraic multigrid (AMG), however, this scalable convergence to discretization accuracy is usually lost. Furthermore, this paper examines the cause of this loss and explores some improvements to standard AMG interpolation that can restore single-cycle convergence to discretization accuracy.

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97 MATHEMATICS AND COMPUTINGalgebraic multigriddiscretization-accuracy solversfull multigrid

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Falgout, Robert D., Manteuffel, Thomas A., McCormick, Stephen F., Mitchell, Wayne B.. 2016-06-24. Discretization-Accuracy Convergence for Full Algebraic Multigrid. https://www.osti.gov/biblio/1840118

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