Abstract
A numerical model was developed to predict the dynamic response of a floating offshore wind turbine system in the time domain, considering the interaction between wind turbines and floater. The responses predicted by the proposed numerical model show good agreements with experiments. Morison's equation overestimates the heave motion of the floating structure with vertical column, while the hydrodynamic damping ratio proposed by Srinivasan et al. gives good predictions. The effect of the aerodynamic damping from the wind turbine is small in the survival condition since the effect of the hydrodynamic damping is significant, while in the operating condition the effect of the aerodynamic damping decreases the dynamic response. Elastic deformation plays an important role in dynamic response of the floating structure. The predicted response was underestimated when the elastic deformation is ignored. The nonlinearity of wave becomes dominant when the water depth is 50m and the elastic modes might be resonant with the higher order harmonic components of nonlinear wave, resulting in the increase of dynamic response of the floating structure.
