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arXiv · 2511.22206

Broken-FEEC on multipatch domains with local refinements

Martin Campos Pinto·Frederik Schnack
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Abstract

This article introduces a novel approach for broken-FEEC (Finite Element Exterior Calculus), extending its application to locally refined spline spaces with non-matching interfaces. Traditional broken-FEEC allows for discontinuous discretizations at patch interfaces, preserving the de Rham structure and offering computational benefits. However, local refinements often lead to numerical artifacts. Our solution involves developing moment-preserving discrete conforming projection operators. These operators are explicit, localized, and metric-independent, ensuring $H^1$ and $H(\text{curl})$ continuity across non-matching interfaces while preserving high-order polynomial moments. This results in broken-FEEC de Rham sequences with accurate strong and weak derivatives, leading to energy-preserving Maxwell solvers that are explicit and virtually free of spurious modes. Numerical simulations confirm the efficacy of our method in eliminating spurious waves.

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Martin Campos Pinto, Frederik Schnack. 2025-11-27. Broken-FEEC on multipatch domains with local refinements. https://arxiv.org/abs/2511.22206

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