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arXiv · 2512.16359

New Fully Discrete Active Flux Methods with Truly Multi-Dimensional Evolution Operators and WENO Reconstruction

Amelie Porfetye·Zhuyan Tang·Shaoshuai Chu·Christiane Helzel·Maria Lukacova-Medvidova
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Abstract

We propose new fully discrete third-order accurate Active Flux and WENO methods based on truly multidimensional evolution operators for the two-dimensional acoustic equations. Building on the method of bicharacteristics, several approximate evolution operators are derived that yield an improved stability of the resulting schemes. A linear stability analysis is applied to determine the maximal CFL number. The schemes are tested extensively on both continuous and discontinuous problems, confirming their robustness and accurate approximation even on coarse grids.

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Amelie Porfetye, Zhuyan Tang, Shaoshuai Chu, Christiane Helzel, Maria Lukacova-Medvidova. 2025-12-18. New Fully Discrete Active Flux Methods with Truly Multi-Dimensional Evolution Operators and WENO Reconstruction. https://arxiv.org/abs/2512.16359

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