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arXiv · 2404.19559

Computational study of numerical flux schemes for mesoscale atmospheric flows in a Finite Volume framework

Nicola Clinco·Michele Girfoglio·Annalisa Quaini·Gianluigi Rozza
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Abstract

We develop, and implement in a Finite Volume environment, a density-based approach for the Euler equations written in conservative form using density, momentum, and total energy as variables. Under simplifying assumptions, these equations are used to describe non-hydrostatic atmospheric flow. The well-balancing of the approach is ensured by a local hydrostatic reconstruction updated in runtime during the simulation to keep the numerical error under control. To approximate the solution of the Riemann problem, we consider four methods: Roe-Pike, HLLC, AUSM+-up and HLLC-AUSM. We assess our density-based approach and compare the accuracy of these four approximated Riemann solvers using two two classical benchmarks, namely the smooth rising thermal bubble and the density current.

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Nicola Clinco, Michele Girfoglio, Annalisa Quaini, Gianluigi Rozza. 2024-04-30. Computational study of numerical flux schemes for mesoscale atmospheric flows in a Finite Volume framework. https://arxiv.org/abs/2404.19559

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