Nonlinear local structural modelling and analysis of the interface for a hybrid wind and wave energy converter concept

Abstract

A hybrid wind and wave energy converter concept, which consists of a spar floating wind turbine and a coaxial wave energy converter named the STC (Spar Torus Combination) concept, has been proposed to achieve better utilization of the ocean space and energy, synergy of the wind and wave conversion, and to reduce the energy cost. The torus moves along the spar cylinder in operational conditions. The critical component of this concept is the interface between wave energy converter and spar floater. Nonlinear local structural modelling of the interface is performed and presented in this paper. The wave energy converter is designed to be connected mechanically to the spar floater by a series of rollers through hydraulic supports. Rubber rollers are used to reduce the contact stress. Different configurations of the spar structure at the interface with the torus are investigated. Quasi-static analyses are carried out. Numerical and experimental studies of the global behavior have been performed, and the results are used as input to the local structural analysis.