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arXiv · 1806.09069

Anisotropic Error Estimates of The Linear Virtual Element Method on Polygonal Meshes

Shuhao Cao·Long Chen
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Abstract

A refined a priori error analysis of the lowest order (linear) Virtual Element Method (VEM) is developed for approximating a model two dimensional Poisson problem. A set of new geometric assumptions is proposed on shape regularity of polygonal meshes. A new universal error equation for the lowest order (linear) VEM is derived for any choice of stabilization, and a new stabilization using broken half-seminorm is introduced to incorporate short edges naturally into the a priori error analysis on isotropic elements. The error analysis is then extended to a special class of anisotropic elements with high aspect ratio originating from a body-fitted mesh generator, which uses straight lines to cut a shape regular background mesh. Lastly, some commonly used tools for triangular elements are revisited for polygonal elements to give an in-depth view of these estimates' dependence on shapes.

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Shuhao Cao, Long Chen. 2018-06-24. Anisotropic Error Estimates of The Linear Virtual Element Method on Polygonal Meshes. https://doi.org/10.1137/17m1154369

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