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Comparison of Two Scale-Dependent Dynamic Subgrid-Scale Models for Simulations of Neutrally Buoyant Shear-Driven Atmospheric Boundary Layer Flows

William Anderson·Sukanta Basu·Chris Letchford
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Abstract

A new scale-dependent dynamic subgrid-scale (SGS) model based on Kolmogorov's scaling hypothesis is presented. This SGS model is utilized in large-eddy simulation of a well-known case study on shear-driven neutral atmospheric boundary layer flows. The results are compared comprehensively with an alternate scale-dependent dynamic SGS model based on the popular Smagorinsky closure. Our results show that, in the context of this particular problem, the scale-dependent dynamic modeling approach is extremely useful, and reproduces several establised results (e.g., the surface layer similarity theory) with fidelity. Results from both the SGS base models are generally in close agreement, although we find a consistent superiority of the Smagorinsky-based SGS model for predicting the inertial range scaling of spectra.

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William Anderson, Sukanta Basu, Chris Letchford. 2006-08-15. Comparison of Two Scale-Dependent Dynamic Subgrid-Scale Models for Simulations of Neutrally Buoyant Shear-Driven Atmospheric Boundary Layer Flows. https://arxiv.org/abs/physics/0608159

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