This paper takes the IEA 15 MW wind turbine blade as the research object, establishes the dynamic model of the aeroelastic system for the blades, analyzes the aeroelastic response during flutter at high tip speed ratio, and conducts in-depth research on the multi-degree-of-freedom coupling characteristics therein. The results show that at high tip speed ratio, the long and flexible blade of this wind turbine undergoes a coupled bending-torsion flutter of pitch-torsion. The vibrations in the three degrees of freedom all contain the natural frequencies of pitch and torsion. However, the maintenance of flutter is sustained by the aerodynamic power work in the pitch and torsion degrees of freedom. There is an obvious coupling phenomenon in the development of the instantaneous aerodynamic power of pitch and torsion. In the direction of yaw, there is basically no energy contribution. There is only weak aerodynamic power throughout the process, and it only undergoes forced vibrations due to the excitation of pitch and torsion because of the coupling characteristics of the blade structure.

wind turbines  /  aeroelasticity  /  bend-twist coupling  /  flutter  /  blade element momentum theory