切变和变风向入流对偏航风力机气动特性的影响研究

The wind shear and variable wind direction are selected, and a computational fluid dynamics (CFD) model for dynamic inflow of the entire wind turbine is established using the double-nested sliding grid method. The variation characteristics of the yawed wind turbine are analyzed. The results show that shear inflow has little effect on the mean torque and axial thrust but increases their relative amplitude, which is further amplified under yaw conditions. Using measured rotor speed data, uniform variable wind direction simulations are performed. Compared to static yaw at the same angle, the mean torque ratio is higher at the end of wind direction variation but lower once speed stabilizes, while the relative amplitude exhibits the opposite trend. Yaw causes the axial high/low load zone to form a 'C' shape, whereas the tangential load distribution resembles a fan or pea shape. Shear inflow shifts the high/low load regions toward the upper/lower half-plane of the rotor. Compared to dynamic yaw at constant rotor speed, variable-speed dynamic yaw yields higher mean loads and fluctuation frequencies in the blade root region, while other regions show lower mean values but greater amplitudes. These findings provide theoretical insights for fatigue design of wind turbines operating in natural wind conditions.