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DOE OSTI · 2337778

Advanced Turbulence Models for Large-Scale Atmospheric Boundary Layer Flows

Tombouldies, Ananias·Min, Misun·Fischer, Paul·Churchfield, Matt·Sprague, Michael
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Abstract

We present high-fidelity large-eddy-simulation (LES) modeling approaches for the turbulent atmospheric boundary layer (ABL) flows. Wind energy is a prime example of an application driven by ABL. Generation of electrical energy from farms of wind turbines at night in the stable ABL is a particularly interesting situation. In this report, we consider the well-known GEWEX (Global Energy and Water Cycle Experiment) Atmospheric Boundary Layer Study (GABLS) stably stratified benchmark LES case. We use a high-order spectral element code Nek5000/RS, which is supported under the DOE's Exascale Computing Project (ECP) Center for Efficient Exascale Discretizations (CEED) project, targeting application simulations on various acceleration-device based exascale computing platforms. In our earlier ANL report, we demonstrated our newly developed subgrid-scale (SGS) models based on high-pass filter (HPF), mean-field eddy viscosity (MFEV), and Smagorinsky (SMG) with no-slip and traction boundary conditions, provided with low-order statistics, convergence and turbulent structure analysis. In this report, we extend the range of our SGS modeling approaches in the context of the mean-field eddy viscosity (MFEV), to include the solution of an SGS turbulent kinetic energy equation (TKE). We demonstrate the model fidelity of Nek5000/RS in comparison to that of AMR-Wind, a block-structured second-order finite-volume code with adaptive-mesh-refinement capabilities, with which we studied scaling performance for both codes in comparison on DOE's leadership computing platforms.

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17 WIND ENERGYatmospheric boundary layerlarge-eddy simulationturbulenceturbulence modeling

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Tombouldies, Ananias, Min, Misun, Fischer, Paul, Churchfield, Matt, Sprague, Michael. 2023-09-28. Advanced Turbulence Models for Large-Scale Atmospheric Boundary Layer Flows. https://doi.org/10.2172/2229259

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