Model tests on GustoMSC’s proprietary Tri-Floater, a semi-submersible floater capable of hosting very large wind turbines, were recently completed.
The tests were carried out on a 1:50 scale model of the Tri-Floater hosting the 15 MW NREL reference wind turbine at the Océanide wave basin in South East France. In the wave basin, the floater was subjected to simultaneous wind, wave, and current loading.
The Tri-Floater design exhibited low accelerations at the wind turbine nacelle during model tests, which was in good agreement with numerical predictions, thanks to the optimized geometry of the submerged structure. Lower accelerations are especially advantageous because they translate to lower load levels and, as a result, lower structure steel weight, which is one of the most important cost drivers in floating wind.
Harsh environment performance
The Tri-Floater model was put through its paces in a variety of environments to show that it is suitable for the majority of floating wind sites currently under consideration. These included both normal operating conditions and extreme conditions that the wind turbine would face during its lifetime, such as those encountered during storms. The extreme sea state was tested with a significant wave height of 13.5 m and a wind speed of 190 km/h at hub height. The Tri-floater ‘passed’ this test, and the results confirm the Tri-ability floater’s to perform in harsh environments.
A large number of more fundamental tests were carried out, investigating various hydrodynamic properties of the floater in greater detail, in addition to representing actual site conditions in the basin. Based on these findings, the numerical models of the Tri-Floater have been calibrated, further improving the quality of GustoMSC’s numerical simulations.
The Tri-Floater design has reached Technology Readiness Level 4: “technology validated in lab” after the model test campaign was completed and numerical models were validated. The Tri-position Floater’s as a contender for commercial tenders in the floating wind space in 2022 and beyond has been strengthened by this achievement.
