Numerical Study of Typhoon Resistance of a Floating Wind Turbine

Abstract

Numerical model of a floating wind turbine is established by reference to the 5 MW wind turbine of American national renewable energy laboratory (NREL). CFD method and Morison formula are used to calculate the wind and wave load under typhoon conditions. According to the geometric distribution of mooring system, the static extreme tension of the chains is estimated, and a safety factor of 3 is used to determine the nominal diameter of the chains. The nonlinear finite element iterative algorithm is adopted to calculate the initial shape and length of the chains, and then the dynamic response of the structure and tensions of the chains under coupled wind and wave actions are obtained through AQWA. The analysis results show that the floating wind turbine is stable under the action of typhoon and waves, the maximum surge displacement of the spar is 10.9m and the maximum pitch angle is 10.4°, and the maximum tension of the mooring system is smaller than the breaking load.