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arXiv · 2010.11831

Data-driven RANS closures for three-dimensional flows around bluff bodies

Jasper P. Huijing·Richard P. Dwight·Martin Schmelzer
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Abstract

In this short note we apply the recently proposed data-driven RANS closure modelling framework of Schmelzer et al. (2020) to fully three-dimensional, high Reynolds number flows: namely wall-mounted cubes and cuboids at Re=40,000, and a cylinder at Re=140,000. For each flow, a new RANS closure is generated using sparse symbolic regression based on LES or DES reference data. This new model is implemented in a CFD solver, and subsequently applied to prediction of the other flows. We see consistent improvements compared to the baseline $k-\omega$ SST model in predictions of mean-velocity in the complete flow domain.

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Jasper P. Huijing, Richard P. Dwight, Martin Schmelzer. 2020-10-22. Data-driven RANS closures for three-dimensional flows around bluff bodies. https://arxiv.org/abs/2010.11831

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