This work evaluates the experimental test results regarding the operational performance of a free-float capable tension leg platform with a 10 MW wind turbine. It covers the platform dynamics in the selected installation area: Ribadeo, Spain. The model and the facility are initially presented, along with the experimental setup and the load cases. The testing campaign includes a software-in-the-loop method to emulate the rotor thrust and the aerodynamic and gyroscopic moments in pitch and yaw. The result sets are structured to start from basic information from system identification cases and continue with responses against regular and irregular waves accompanied by steady and stochastic wind scenarios. The performance in operational and extreme conditions is assessed as well as fault scenarios. The experiments demonstrate auspicious motion dynamics and mooring line behavior when examined against class society rules.

This paper reviews experimental methods for testing floating wind turbines. The techniques covered include early-stage and up-to-date approaches such as a porous disc method and hybrid model testing. First, the challenges induced by Froude and Reynolds similitudes and the importance of the various aerodynamic phenomena are discussed. The experimental methods are evaluated based on their cost, versatility, requirements, and limitations. The work primarily focuses on representing aerodynamic loads via hybrid and physical rotor testing, and a preliminary classification is proposed to facilitate the selection of the approaches. The work does not aim to identify an optimal method, but it provides insights into each method’s distinctive features, serving as a roadmap for selecting the most appropriate methodology based on the specific testing goals and level of accuracy. Overall, this study offers a comprehensive resource for testing the coupled hydrodynamic and aerodynamic performance of floating wind turbines. The conclusions offer guidance for selecting an appropriate methodology based on the desired testing outcome.

This paper presents a review of the hybrid model testing strategies for floating wind turbines. It examines the method’s accuracy, advantages, and weaknesses. The hybrid approach refers to tests that combine physical testing and numerical simulation in wave basin or wind tunnels. The coupling between the physical and numerical part is done via actuators. The different forms of hybrid testing adopted by researchers – such as robots, cable, propeller’s actuators – are discussed and evaluated. A guidance is given for selecting the hybrid style suitable for model testing. It is concluded that hybrid testing is cost-efficient and versatile but its fidelity relays on the accuracy of the numerical tool. Also, the test’s objectives are a key factor for choosing the suitable hybrid testing methodology.

This work presents a comparison between the hydrodynamic behavior of three and four-column semi-submersibles. The platforms are the NAUTILUS and the OO-star semi-submersibles, with the DTU 10MW wind turbine. Both models are described, and simulations in wind and wave conditions are made using OpenFast. The natural frequencies and the response amplitude operators are calculated. The motions of the platform, the tower bending moment, and the nacelle acceleration are evaluated. These results are assessed to understand whether a particular geometry presents advantages over another. It is concluded that the platform geometry has a slight effect on the platform pitch motion, and economic factors should be considered for model selection.