Effect of Coriolis force on a wind farm wake

Abstract

Abstract The effect of the Coriolis force on the wake of a wind farm in a conventionally neutral and a stable boundary layer is investigated using large eddy simulations. We find that the average flow angle varies with the downstream position in the wind farm. In the entrance region of the wind farm, the flow blockage and wind veer create a positive gradient of the vertical flux 〈 u ′ w ′ ¯ 〉 at hub-height, which causes a counter-clockwise flow deflection in the Northern hemisphere, when observed from above. Further downstream, the vertical entrainment of air from the upper layers of the boundary layer generates a negative gradient of the vertical flux 〈 u ′ w ′ ¯ 〉 at hub-height, which results in a clockwise flow deflection in the Northern hemisphere. The deflection is more pronounced for the stable boundary layer than for the conventionally neutral boundary layer. In addition, we find that the wake deflection has a significant impact on the power production of turbines further downstream in the wind farm.