Influence of the horizontal component of Earth's rotation on wind turbine wakes

Wind turbines with large rotor diameters create wakes which are affected by the rotation of the earth. Aside from creating horizontal mean velocity veer, the Coriolis force, caused by earth's rotation, also results in wake deflection and turbulence kinetic energy redistribution. In atmospheric turbulence, the horizontal component of Earth's rotation is often neglected since its forcing magnitude is small compared to buoyant forces. However, at lower latitudes, the horizontal component will cause vertical deflection and redistribution of the same order as the horizontal wake deflection and distribution imposed by the vertical component. Large Eddy Simulations (LES) using uniform laminar inflow, along with more realistic neutrally and stably stratified atmospheric boundary layer inflow conditions are used to study the effect of the horizontal component. Simulations performed at a latitude of 450 suggest that the horizontal component cannot be neglected in the study of wind farms since the horizontal component's effect in wind turbine planetary boundary layer flows manifests most directly in the vertical entertainment of kinetic energy. A low-order Coriolis force-induced wake deflection model is proposed and tested against numerical results for uniform inflow conditions.