Numerical model for 6 DoF dynamics of offshore floating wind turbines: A code-to-code comparison between OpenFAST and MOST

Preprint submitted to RENEW 2024 conference.

This paper presents a novel nonlinear, time-domain numerical model for simulating offshore floating wind turbines, known as MOST. The tool evaluates platform dynamics in six degrees of freedom, power production, and blade load cycles. It integrates aerodynamics and hydrodynamics within the Matlab/Simulink environment, simplifying computations through pre-processed look-up tables for aerodynamic and mooring loads. In a comparative analysis with OpenFAST, using a 15 MW reference wind turbine and the VolturnUS-S platform, the model demonstrates similar precision (NRMSE 4%) while reducing simulation time by up to 75%. The study covers ten different metocean conditions, emphasizing robustness in several metocean scenarios. This research advances simulation capabilities for offshore wind energy systems, providing a powerful tool for researchers and engineers to effectively simulate and analyze complex offshore environments, thereby enhancing the development of offshore renewable energy projects.