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arXiv · 1606.04660

Error analysis of a variational multiscale stabilization for convection-dominated diffusion equations in 2d

Guanglian Li·Daniel Peterseim·Mira Schedensack
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Abstract

We formulate a stabilized quasi-optimal Petrov-Galerkin method for singularly perturbed convection-diffusion problems based on the variational multiscale method. The stabilization is of Petrov-Galerkin type with a standard finite element trial space and a problem-dependent test space based on pre-computed fine-scale correctors. The exponential decay of these correctors and their localisation to local patch problems, which depend on the direction of the velocity field and the singular perturbation parameter, is rigorously justified. Under moderate assumptions, this stabilization guarantees stability and quasi-optimal rate of convergence for arbitrary mesh P\'eclet numbers on fairly coarse meshes at the cost of additional inter-element communication.

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Guanglian Li, Daniel Peterseim, Mira Schedensack. 2016-06-15. Error analysis of a variational multiscale stabilization for convection-dominated diffusion equations in 2d. https://arxiv.org/abs/1606.04660

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