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arXiv · 1507.03199

Parameter-robust discretization and preconditioning of Biot's consolidation model

Jeonghun J. Lee·Kent-Andre Mardal·Ragnar Winther
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Abstract

Biot's consolidation model in poroelasticity has a number of applications in science, medicine, and engineering. The model depends on various parameters, and in practical applications these parameters ranges over several orders of magnitude. A current challenge is to design discretization techniques and solution algorithms that are well behaved with respect to these variations. The purpose of this paper is to study finite element discretizations of this model and construct block diagonal preconditioners for the discrete Biot systems. The approach taken here is to consider the stability of the problem in non-standard or weighted Hilbert spaces and employ the operator preconditioning approach. We derive preconditioners that are robust with respect to both the variations of the parameters and the mesh refinement. The parameters of interest are small time-step sizes, large bulk and shear moduli, and small hydraulic conductivity.

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Jeonghun J. Lee, Kent-Andre Mardal, Ragnar Winther. 2015-07-12. Parameter-robust discretization and preconditioning of Biot's consolidation model. https://arxiv.org/abs/1507.03199

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