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arXiv · 1608.06700

Runge-Kutta discontinuous local evolution Galerkin methods for the shallow water equations on the cubed-sphere

Yangyu Kuang·Kailiang Wu·Huazhong Tang
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Abstract

The paper develops high order accurate Runge-Kutta discontinuous local evolution Galerkin (RKDLEG) methods on the cubed-sphere grid for the shallow water equations (SWEs). Instead of using the dimensional splitting method or solving one-dimensional Riemann problem in the direction normal to the cell interface, the RKDLEG methods are built on genuinely multi-dimensional approximate local evolution operator of the locally linearized SWEs on a sphere by considering all bicharacteristic directions. Several numerical experiments are conducted to demonstrate the accuracy and performance of our RKDLEG methods, in comparison to the Runge-Kutta discontinuous Galerkin method with Godunov's flux etc.

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Yangyu Kuang, Kailiang Wu, Huazhong Tang. 2016-08-24. Runge-Kutta discontinuous local evolution Galerkin methods for the shallow water equations on the cubed-sphere. https://doi.org/10.4208/nmtma.2017.s09

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