Wind Turbine Impacts on Its Semi-Submersible Floating Supporting System for Phase II of OC4

The motion response of floating supporting system for offshore wind turbine is critical in designing and confirming the safety and efficiency of wind turbine. This paper aims to study the wind turbine impacts on its semi-submersible floating system for Phase II of OC4, which is a project to compare dynamic computer codes and models used to design offshore wind turbines and support structures by International Energy Agency. Firstly, the validation of wave generation and absorbing has been performed to guarantee the accuracy of wave. Then, the grid convergence is used to eliminate the influence of grid on the results of simulation results. At last, motion of the semi-submersible floating system in specific wave has been compared between without wind turbine and with equivalent wind turbine. The equivalent forces and moments of the NREL 5-MW in different wind speeds (V=5m/s, 7m/s and 11.4m/s) have been exerted in the rotation center of the semi-submersible floating system. The results show the influences of the wind turbine on the supporting system in wave that give the guidance to the design of floating supporting system of offshore floating wind turbine.