Large eddy simulations of wind turbine wakes in typical complex topographies

There is a need to clarify the coupling characteristics of terrain-induced wind fields and wind turbine-induced wake in wind farm micrositing. However, research investigating the effect of hill shape on this interaction is lacking. In addition, during the optimization of the layout of the turbines over topographies, the flow behind the turbines should be predicted in a fast way. After obtaining the wake flow of the turbine mounted on flat terrain and the flow over the topographies, there are mainly two superposition methods to predict the turbine wake flow over the topographies. One is to add the wind deficit following the location with a vertical distance of the hub height (D-line). The other is to add the wind deficit following the streamline starting from the turbine center (B-line). It remains unknown to what extent these two superposition methods can be adopted. Therefore, the effects of hill shape, wind turbine size, and turbine location are investigated. When the wind deficit, obtained from modeling the wake flow of the turbine mounted on flat terrain, is superposed following B-line, the results are overall better than those when following D-line.