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arXiv · 2507.01736

An energy-based discontinuous Galerkin method for the wave equation with nonsmooth solutions

Yangxin Fu·Yan Jiang·Siyang Wang
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Abstract

We develop a stable and high-order accurate discontinuous Galerkin method for the second order wave equation, specifically designed to handle nonsmooth solutions. Our approach integrates the energy-based discontinuous Galerkin method with the oscillation-free technique to effectively suppress spurious oscillations near solution discontinuities. Both stability analysis and apriori error estimates are established for common choices of numerical fluxes. We present a series of numerical experiments to confirm the optimal convergence rates for smooth solutions and its robustness in maintaining oscillation-free behavior for nonsmooth solutions in wave equations without or with nonlinear source terms.

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Yangxin Fu, Yan Jiang, Siyang Wang. 2025-07-02. An energy-based discontinuous Galerkin method for the wave equation with nonsmooth solutions. https://arxiv.org/abs/2507.01736

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