Modeling wind direction changes in large eddy simulations using a rotating reference frame

The wind direction in atmospheric boundary layers changes continuously due to large-scale weather effects. An accurate representation of dynamic wind direction changes in large eddy simulations (LES) is essential to study the effect of varying wind directions on the performance of large wind farms. However, modeling large-scale wind direction changes in LES of wind farms is still a major challenge. In this study, we introduce a new technique to model wind direction changes in LES, which can be obtained from mesoscale simulations or field measurements. We propose a method in which the simulation domain is treated as a non-inertial rotating reference frame. The primary benefit of our approach is that it is straightforward to implement and reproduces desired wind direction changes excellently. We show that atmospheric measurements of the wind direction can be reproduced by our method. To underline the importance of the method, we conclude with a representative scenario, which shows that dynamic wind direction changes can affect the performance of large wind farms.