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arXiv · 2006.05585

A simple virtual element-based flux recovery on quadtree

Shuhao Cao
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Abstract

In this paper, we introduce a simple local flux recovery for $\mathcal{Q}_k$ finite element of a scalar coefficient diffusion equation on quadtree meshes, with no restriction on the irregularities of hanging nodes. The construction requires no specific ad hoc tweaking for hanging nodes on $l$-irregular ($l\geq 2$) meshes thanks to the adoption of virtual element families. The rectangular elements with hanging nodes are treated as polygons as in the flux recovery context. An efficient a posteriori error estimator is then constructed based on the recovered flux, and its reliability is proved under common assumptions, both of which are further verified in numerics.

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Shuhao Cao. 2020-06-10. A simple virtual element-based flux recovery on quadtree. https://arxiv.org/abs/2006.05585

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