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arXiv · 1407.4377

Recovery-Based Error Estimators for Diffusion Problems: Explicit Formulas

Zhiqiang Cai·Shun Zhang
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Abstract

We introduced and analyzed robust recovery-based a posteriori error estimators for various lower order finite element approximations to interface problems in [9, 10], where the recoveries of the flux and/or gradient are implicit (i.e., requiring solutions of global problems with mass matrices). In this paper, we develop fully explicit recovery-based error estimators for lower order conforming, mixed, and non- conforming finite element approximations to diffusion problems with full coefficient tensor. When the diffusion coefficient is piecewise constant scalar and its distribution is local quasi-monotone, it is shown theoretically that the estimators developed in this paper are robust with respect to the size of jumps. Numerical experiments are also performed to support the theoretical results.

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Zhiqiang Cai, Shun Zhang. 2014-07-16. Recovery-Based Error Estimators for Diffusion Problems: Explicit Formulas. https://arxiv.org/abs/1407.4377

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