Dynamic response of a floating offshore wind turbine structure to extreme wave loading in nonlinear, directional seas

Notwithstanding the present-day oil prices, the large amounts of greenhouse gases set free by burning fossil fuels, have already a tremendous impact on the weather extremes. As further climate change endangers our societies, the transition to renewables must be fast. Due to its high resource availability and high technology maturity, offshore wind remains the most promising to facilitate this transition. As offshore wind turbines are currently founded on the sea floor, their installation is limited to water depths smaller than 50m. In order to extend their application to deeper waters with larger wind energy potential, floating offshore wind turbines are strongly recommended. Currently, the design of floating offshore wind turbines is entirely based upon the elaborate experience from the oil and gas industry in designing floating rigs. Due to the differing structural behaviour, these design practices cannot properly account for the hydrodynamic response of floating offshore wind turbines.

This doctoral research wants to contribute to a more safe and efficient floating offshore wind turbine design by assessing the impact of non-Gaussian seas on floating offshore wind turbines. To this end, the motion of the floating offshore wind turbines is studied through physical and numerical (Computational Fluid Dynamics) modelling and the mechanisms responsible for enhancing the wave steepness characteristic for extreme wave events are taken along.