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arXiv · 1507.02557

GPU-accelerated discontinuous Galerkin methods on hybrid meshes

Jesse Chan·Zheng Wang·Axel Modave·Jean-Francois Remacle·T. Warburton
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Abstract

We present a time-explicit discontinuous Galerkin (DG) solver for the time-domain acoustic wave equation on hybrid meshes containing vertex-mapped hexahedral, wedge, pyramidal and tetrahedral elements. Discretely energy-stable formulations are presented for both Gauss-Legendre and Gauss-Legendre-Lobatto (Spectral Element) nodal bases for the hexahedron. Stable timestep restrictions for hybrid meshes are derived by bounding the spectral radius of the DG operator using order-dependent constants in trace and Markov inequalities. Computational efficiency is achieved under a combination of element-specific kernels (including new quadrature-free operators for the pyramid), multi-rate timestepping, and acceleration using Graphics Processing Units.

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Jesse Chan, Zheng Wang, Axel Modave, Jean-Francois Remacle, T. Warburton. 2015-07-09. GPU-accelerated discontinuous Galerkin methods on hybrid meshes. https://doi.org/10.1016/j.jcp.2016.04.003

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