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arXiv · 2202.00295

A novel Large Eddy Simulation model for the Quasi-Geostrophic Equations in a Finite Volume setting

Michele Girfoglio·Annalisa Quaini·Gianluigi Rozza
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Abstract

We present a Large Eddy Simulation (LES) approach based on a nonlinear differential low-pass filter for the simulation of two-dimensional barotropic flows with under-refined meshes. For the implementation of such model, we choose a segregated three-step algorithm combined with a computationally efficient Finite Volume method. We assess the performance of our approach on the classical double-gyre wind forcing benchmark. The numerical experiments we present demonstrate that our nonlinear filter is an improvement over a linear filter since it is able to recover the four-gyre pattern of the time-averaged stream function even with extremely coarse meshes. In addition, our LES approach provides an average kinetic energy that compares well with the one computed with a Direct Numerical Simulation.

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Michele Girfoglio, Annalisa Quaini, Gianluigi Rozza. 2022-02-01. A novel Large Eddy Simulation model for the Quasi-Geostrophic Equations in a Finite Volume setting. https://arxiv.org/abs/2202.00295

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