Implementing Large-Eddy Simulation Capability in a Compressible Mesoscale Model

AbstractThe large size of modern wind turbines and wind farms triggers processes above the surface layer, which extend to the junction between microscales and mesoscales, and pushes the limits of existing approaches to predict the wind. The main objectives of this study are thus to introduce and evaluate an approach that will better account for physical processes within the atmospheric boundary layer (ABL), and allow for both microscale and mesoscale modeling. The proposed method, in which mathematical model and main numerical aspects are presented, combines a mesoscale approach with a large-eddy simulation (LES) model based on the Compressible Community Mesoscale Model (MC2). It is evaluated relying on a shear-driven ABL case allowing the authors to assess the model behavior at very high resolution as well as more specific numerical aspects such as the vertical discretization and time and space splitting of turbulence-related terms. The proposed LES-capable mesoscale model is shown to perform on par with...