Impact of Various Coupled Motions on the Aerodynamic Performance of a Floating Offshore Wind Turbine Within the Wind–Rain Field

This study employed a computational fluid dynamics model with an overset mesh technique to investigate the thrust and power of a floating offshore wind turbine (FOWT) under platform floating motion in the wind–rain field. The impact of rainfall on aerodynamic performance was initially examined using a stationary turbine model in both wind and wind–rain conditions. Subsequently, the study compared the FOWT’s performance under various single degree-of-freedom (DOF) motions, including surge, pitch, heave, and yaw. Finally, the combined effects of wind–rain fields and platform motions involving two DOFs on the FOWT’s aerodynamics were analyzed and compared. The results demonstrate that rain negatively impacts the aerodynamic performance of both the stationary turbines and FOWTs. Pitch-dominated motions, whether involving single or multiple DOFs, caused significant fluctuations in the FOWT aerodynamics. The combination of surge and pitch motions created the most challenging operational environment for the FOWT in all tested scenarios. These findings highlighted the need for stronger construction materials and greater ultimate bearing capacity for FOWTs, as well as the importance of optimizing designs to mitigate excessive pitch and surge.