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DOE OSTI · 1772894

The DPG Method for the Convection-Reaction Problem Revisited

Demkowicz, Leszek·Roberts, Nathan V.
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Abstract

We study both conforming and non-conforming versions of the practical DPG method for the convection-reaction problem. We determine that the most common approach for DPG stability analysis (construction of a local Fortin operator) is infeasible for the convection-reaction problem. We then develop a line of argument based on the direct construction of a global Fortin operator; we find that employing a polynomial enrichment for the test space does not suffice for this purpose, motivating the introduction of a (two-element) subgrid mesh. The argument combines mathematical analysis with numerical experiments

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Demkowicz, Leszek, Roberts, Nathan V.. 2021-03-01. The DPG Method for the Convection-Reaction Problem Revisited. https://doi.org/10.2172/1772894

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