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arXiv · 1702.07749

Well-balanced mesh-based and meshless schemes for the shallow-water equations

Alexander Bihlo·Scott MacLachlan
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Abstract

We formulate a general criterion for the exact preservation of the "lake at rest" solution in general mesh-based and meshless numerical schemes for the strong form of the shallow-water equations with bottom topography. The main idea is a careful mimetic design for the spatial derivative operators in the momentum flux equation that is paired with a compatible averaging rule for the water column height arising in the bottom topography source term. We prove consistency of the mimetic difference operators analytically and demonstrate the well-balanced property numerically using finite difference and RBF-FD schemes in the one- and two-dimensional cases.

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Alexander Bihlo, Scott MacLachlan. 2017-02-24. Well-balanced mesh-based and meshless schemes for the shallow-water equations. https://arxiv.org/abs/1702.07749

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