Floating wind turbines can experience very large hydrodynamic loads in rough seas. As offshore wind turbines grow in size, elasticity in the hull could be an important parameter, as for other (very) large floating structures. However, today’s design methods decouple the hydrodynamics from the structural models: the environmental loads are computed on a rigid platform model and applied as external loads to the hull during structural analysis.
Few models have been developed to analyse internal responses in the hull of floating wind turbines considering flexibility [1]. They use either the linear potential flow theory [2], or the generalised Morison formula. Several methods have been tested and show relatively good agreements with experimental measurements on rigid hulls [3], except in extreme conditions where nonlinear effects can be important. The objective of this study is to propose a new approach including nonlinear hydrodynamics and strong hydro-elastic coupling, which can be applied to fixed or floating wind turbines.