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arXiv · 2302.04836

Validation of an OpenFOAM-based solver for the Euler equations with benchmarks for mesoscale atmospheric modeling

Abstract

Within OpenFOAM, we develop a pressure-based solver 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. For the stabilization of the Euler equations and to capture sub-grid processes, we consider two Large Eddy Simulation models: the classical Smagorinsky model and the one equation eddy-viscosity model. To achieve high computational efficiency, our solver uses a splitting scheme that decouples the computation of each variable. The numerical results obtained with our solver are validated against numerical data available in the literature for two classical benchmarks: the rising thermal bubble and the density current. Through qualitative and quantitative comparisons, we show that our approach is accurate. This work is meant to lay the foundation for a new open source package specifically created for quick assessment of new computational approaches for the simulation of atmospheric flows at the mesoscale level

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Michele Girfoglio, Annalisa Quaini, Gianluigi Rozza. 2023-02-09. Validation of an OpenFOAM-based solver for the Euler equations with benchmarks for mesoscale atmospheric modeling. https://arxiv.org/abs/2302.04836

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