3 - Aeroelasticity and structural dynamics of wind turbines

In the present chapter, the aeroelastic modeling and optimized design of modern megawatt-scale wind turbines are addressed. In the first part of the chapter, the aeroelastic equations of motion for the flexible wind turbine components and the dynamics of the full wind turbine system are presented in the context of beam theory, multi-body dynamic analysis and finite element method. In the second part, the main aspects relating to an improved aeroelastic design are discussed. First, the nature of the external loads on a wind turbine is described. Then, aeroelastic instability problems encountered in the past or expected in future designs, methods for improving the aeroelastic behavior of wind turbines and some future trends concerning aeroelastic design are discussed.