Validation of a finite element based simulation approach for offshore wind turbines within IEA Wind Annex XXIII - simulation challenges and results for a 5-MW turbine on a tripod substructure

This paper presents the validation of ADCoS-Offshore, a newly developed design tool for simulation of offshore wind turbines (OWT). ADCoS-Offshore allows the modeling of branched support structures as Finite Element (FE) beam models in a fully coupled simulation of overall turbine dynamics and it is validated within the Offshore Code Comparison Collaboration (OC3). OC3 is part of the International Energy Agency Wind Annex XXIII. Within this project a realistic 5 MW wind turbine with a tripod substructure is modelled and a set of load cases is run by different partners with several design tools. In this way the performance of ADCoS-Offshore is shown. Furthermore the impact of various modeling assumptions is shown.