Addressing the Grid-Size Sensitivity Issue in Large-Eddy Simulations of Stable Boundary Layers
Yi Dai, Sukanta Basu, Björn Maronga, Stephan R. de Roode
Abstract
Abstract We have identified certain fundamental limitations of a mixing-length parametrization used in a popular turbulent kinetic energy-based subgrid-scale model. Replacing this parametrization with a more physically realistic one significantly improves the overall quality of the large-eddy simulation (LES) of stable boundary layers. For the range of grid sizes considered here (specifically, 1 m–12.5 m), the revision dramatically reduces the grid-size sensitivity of the simulations. Most importantly, the revised scheme allows us to reliably estimate the first- and second-order statistics of a well-known LES intercomparison case, even with a coarse grid size of O(10 m).
Topics & Concepts
Parametrization (atmospheric modeling)Sensitivity (control systems)Boundary (topology)GridRange (aeronautics)Statistical physicsApplied mathematicsMathematicsQuality (philosophy)Boundary value problemTurbulenceKinetic energyComputer scienceBoundary layerMathematical optimizationScheme (mathematics)AlgorithmPhysicsGrid method multiplicationStability (learning theory)Term (time)Fluid Dynamics and Turbulent FlowsComputational Fluid Dynamics and AerodynamicsCombustion and flame dynamics