Dynamic Responses and Wake Characteristics of a Floating Offshore Wind Turbine in Yawed Conditions

Numerical simulations of a floating offshore wind turbine (FOWT) in yawed conditions are carried out using a coupled large eddy simulation and aero-hydro-moor-servo dynamics code. The inflow wind is an atmospheric boundary layer inflow simulated by large eddy simulation with a long duration. Two scenarios with yaw angles of 15° and 30° for a wind turbine are investigated, and the aerodynamics, hydrodynamics, and wake characteristics are compared against a non-yaw scenario. The study concludes that as the yaw angle increases, the rotor power of FOWT decreases. However, the rotor thrust of the 15° yaw angle is slightly higher compared with the non-yaw scenario. In terms of platform motions, there is minimal disparity for surge and pitch between the 15° yaw angle and non-yaw conditions. When the yaw angle is 30°, both surge and pitch are notably reduced. The sway increases with the yaw angle because of the crosswise component of rotor thrust. Furthermore, we observe a faster wake recovery and more pronounced wake deflection with an increasing yaw angle. These observations have a positive impact on the inflow wind condition and power generation of downstream wind turbines.