Research for structural responses and stability caused by wind-rain loads for large wind turbine considering yaw effect

Taking a 5 MW horizontal wind turbine developed independently by Nanjing University of Aeronautics and Astronautics as an example, the flow field of wind turbine considering different yaw angles (0°, 5°, 10°, 20°, 30° and 45°) was simulated based on the computational fluid dynamics (CFD) method firstly. And the discrete phase model (DPM) was added and the iterative computations of rain and wind loads were carried out after the effectiveness of the numerical simulation being verified. And then the influence sales of different yaw angles on wind-driven rainfall, raindrop additional force and equivalent pressure coefficient on tower and blades were studied. On the basis of this, the structural responses, the buckling stability and the ultimate bearing capacity of large wind turbine were carried out the qualitative and quantitative analysis for different yaw angles by the finite element method under wind load action and simultaneous actions of wind and rain loads. Studies show that the flow field characteristics and mechanical properties caused by wind and rain loads of wind turbine are significantly affected with the change of yaw angles. The displacement and internal force responses of wind turbine system are increased under simultaneous action of wind and rain loads. And then the buckling stability and ultimate bearing capacity of wind turbine are reduced under simultaneous action of wind and rainloads. The conclusions can provide references for load forecast of such wind turbines under extreme climates and complex conditions. © 2020, Solar Energy Periodical Office Co., Ltd. All right reserved.