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arXiv · 1701.04834

High-order schemes for the Euler equations in cylindrical/spherical coordinates

Sheng Wang·Eric Johnsen
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Abstract

We consider implementations of high-order finite difference Weighted Essentially Non-Oscillatory (WENO) schemes for the Euler equations in cylindrical and spherical coordinate systems with radial dependence only. The main concern of this work lies in ensuring both high-order accuracy and conservation. Three different spatial discretizations are assessed: one that is shown to be high-order accurate but not conservative, one conservative but not high-order accurate, and a new approach that is both high-order accurate and conservative. For cylindrical and spherical coordinates, we present convergence results for the advection equation and the Euler equations with an acoustics problem; we then use the Sod shock tube and the Sedov point-blast problems in cylindrical coordinates to verify our analysis and implementations.

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Sheng Wang, Eric Johnsen. 2017-01-17. High-order schemes for the Euler equations in cylindrical/spherical coordinates. https://arxiv.org/abs/1701.04834

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