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arXiv · 1805.04196

A Polygonal Discontinuous Galerkin Method with Minus One Stabilization

Silvia Bertoluzza·Daniele Prada
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Abstract

We propose a Discontinuous Galerkin method for the Poisson equation on polygonal tessellations in two dimensions, stabilized by penalizing, locally in each element $K$, a residual term involving the fluxes, measured in the norm of the dual of $H^1(K)$. The scalar product corresponding to such a norm is numerically realized via the introduction of a (minimal) auxiliary space inspired by the Virtual Element Method. Stability and optimal error estimates in the broken $H^1$ norm are proven under a weak shape regularity assumption allowing the presence of very small edges. The results of numerical tests confirm the theoretical estimates.

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Silvia Bertoluzza, Daniele Prada. 2018-05-10. A Polygonal Discontinuous Galerkin Method with Minus One Stabilization. https://doi.org/10.1051/m2an/2020059

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