Numerical Simulation Of Fluid Structure Coupling Of Two Different Scale Horizontal-Axis Wind Turbine Blades

Use of energy is closely related to the development of human society. With the global environment pollution problems caused by fossil fuels is getting worse and worse, the clean and renewable energy gets more and more attention by worldwide countries, wherein wind energy as one of the clean energy, is developing faster and faster. With the development of wind power technology,1.5 MW and 2 MW wind turbines become today’s mainstream models, because the wind turbine blade’s features:chord is short, radius is long. Fluid structure coupling of wind and blade interaction makes significant impact on the wind turbine blade structural and aerodynamic characteristics. In this paper, the specific contents are as follows:First of all, this article expounds the basic knowledge of fluid structure coupling, fluid structure coupling classification and calculation methods are introduced. During fluid structure coupling calculation, using the equivalent modeling method and compared with experimental modal frequency mode respectively to prove the feasibility of equivalent structure modeling.By doing the single and two way fluid structure coupling calculation of NREL Phase VI wind turbines, research shows that:under the single and two way coupling, blade structural characteristics are consistent, hub position appears stress concentration, the position of the biggest blade deformation is at the blade tip; under two way coupling,the aerodynamic characteristics response of blade deformation can be analyzed, for Phase VI wind turbine because of its small rotor diameter, blade deformation is not obvious, and the fluid structure coupling effect of wind power output can be ignored.In order to more representative, proceed doing two way fluid structure coupling calculation in uniform and yaw flow conditions with the 2 MW Tjaereborg wind turbine, the stress concentration appears in the middle and outer part of the wind turbine blade, it is diffident with Phase VI wind turbine. In uniform flow condition, the coupling effect makes significant impact on blade output at middle and high wind speed; in yaw flow condition, blade deformation and stress distribution changing periodically because of the blade aerodynamic load changing with blade azimuth periodically, and in some azimuth position the blade deformation and stress concentration is more serious than uniform flow condition.