Design and Hydro-aero-elastic Modeling of a Multi Leg Mooring Concept for Floating Wind Turbine Applications

Abstract

A multi-cylinder floating structure with conventional catenary mooring lines is presented for supporting a 10 MW Wind Turbine (WT). A design-oriented solution method accounting for the coupled dynamics of the floating structure in the frequency domain is presented and the corresponding RAO s are calculated. The hydrodynamic characteristics are determined using matched axisymmetric eigenfunction expansions. A reduced order model provides the linearized loading contributed by the WT (gravitational, inertial and aerodynamic). In addition, time domain coupled hydro-servo-aero-elastic simulations of the floating structure are performed considering wave excitation described by a white noise spectrum whereby the effective RAO s are computed from the corresponding time signals. Comparison between the two methods is performed at the RAO s level for representative wind speeds and wave heading angles.