Offshore Code Comparison Collaboration Continuation Within IEA Wind Task 30: Phase II Results Regarding a Floating Semisubmersible Wind System

TLDR

Offshore wind turbines rely on integrated simulation tools that model coupled wind, aerodynamic, structural, control, wave, current, hydrodynamic, mooring, and foundation dynamics. The study reports the latest results from the Offshore Code Comparison Collaboration Continuation project under IEA Wind Task 30. In Phase II, multiple simulation codes modeled the coupled dynamic response of a 5‑MW turbine on a floating semisubmersible in 200 m water, and load‑case predictions were compared to assess different model features. The comparisons deepened understanding of floating wind turbine dynamics, validated modeling approximations, and led to code improvements that raise the overall standard of offshore wind turbine modeling.

Abstract

Offshore wind turbines are designed and analyzed using comprehensive simulation tools (or codes) that account for the coupled dynamics of the wind inflow, aerodynamics, elasticity, and controls of the turbine, along with the incident waves, sea current, hydrodynamics, mooring dynamics, and foundation dynamics of the support structure. This paper describes the latest findings of the code-to-code verification activities of the Offshore Code Comparison Collaboration Continuation project, which operates under the International Energy Agency Wind Task 30. In the latest phase of the project, participants used an assortment of simulation codes to model the coupled dynamic response of a 5-MW wind turbine installed on a floating semisubmersible in 200 m of water. Code predictions were compared from load case simulations selected to test different model features. The comparisons have resulted in a greater understanding of offshore floating wind turbine dynamics and modeling techniques, and better knowledge of the validity of various approximations. The lessons learned from this exercise have improved the participants’ codes, thus improving the standard of offshore wind turbine modeling.