The wind-wave tunnel test of a tension-leg platform type floating offshore wind turbine

In this work, a tension-leg platform (TLP) type floating offshore wind turbine (FOWT) system was proposed, which was based on the National Renewable Energy Laboratory 5MW offshore wind turbine model. Taking the coupled effect of dynamic response of the top wind turbine, support tower structure, and lower mooring system into consideration, the 1/60 scale model test for investigating the coupled wind-wave effect on performance of the floating wind turbine system was done in Harbin Institute of Technology's wind tunnel and wave flume joint laboratory. In addition, numerical simulations corresponding to the scale model tests have been performed by advanced numerical tools. The results of model tests and numerical simulations have a good agreement, so the availability of the numerical model has been verified. Furthermore, to improve the performance of the TLP system, one tentative strategy adding mooring lines to the TLP system was proposed, and the model test results of the two TLP systems were compared with each other. As a result, the motion responses of the floating platform and the force levels of tension legs were effectively reduced by the additional mooring chains. The new TLP FOWT system might play an active and instructive role in the development of future FOWT system.