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arXiv · 1106.3585

Proper Orthogonal Decomposition Closure Models For Turbulent Flows: A Numerical Comparison

Zhu Wang·Imran Akhtar·Jeff Borggaard·Traian Iliescu
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Abstract

This paper puts forth two new closure models for the proper orthogonal decomposition reduced-order modeling of structurally dominated turbulent flows: the dynamic subgrid-scale model and the variational multiscale model. These models, which are considered state-of-the-art in large eddy simulation, together with the mixing length and the Smagorinsky closure models, are tested in the numerical simulation of a 3D turbulent flow around a circular cylinder at Re = 1,000. Two criteria are used in judging the performance of the proper orthogonal decomposition reduced-order models: the kinetic energy spectrum and the time evolution of the POD coefficients. All the numerical results are benchmarked against a direct numerical simulation. Based on these numerical results, we conclude that the dynamic subgrid-scale and the variational multiscale models perform best.

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Zhu Wang, Imran Akhtar, Jeff Borggaard, Traian Iliescu. 2011-06-17. Proper Orthogonal Decomposition Closure Models For Turbulent Flows: A Numerical Comparison. https://doi.org/10.1016/j.cma.2012.04.015

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