Investigation of the Aerodynamic Loads of Horizontal Axis Wind Turbines Blade

Wind energy is an environmentally friendly option to ensure energy security during a period when fossil fuel reserves determine the long-term development of the economy. To improve wind turbines’ ability to produce electricity, blades are becoming larger and more flexible. This increasing flexibility and size of wind turbine blades leads to study their dynamic behavior in order to avoid the fatigue of the structure and consequently its damage. Most of the current research treats linear models built on hypothesis of small deflections. This hypothesis is not applicable anymore for the purpose of designing large flexible blade considering that such structures frequently undergo large deflections. A novel formulation considering geometric non-linearity problems and investigates the impact of rotation speed on the natural frequency variations has been established. A Newmark method combined with Newton Raphson schema is target to compute the wind turbine response in the time domain, considering both linear and nonlinear analyses, while accounting for aerodynamic loads and a flapwise and an edgewise deflection curves were extracted. The findings indicate that the natural frequencies seem sensitive to the nonlinearity and the elevation of the wind velocity.