Advanced Finite Element Analysis for High Power Wind Energy Systems

In order to build light-weight wind power rotor blades it is necessary to design thin walled parts so that the weight of the rotor blade is no longer the limiting factor for the size of the plant. Up until now it has been necessary to use a complex three-dimensional calculation with the help of the finite elements method (FEM). In this thesis special finite line elements are introduced, with which the numerical determination of the shear stress distribution due to cross-sectional bending and torsion as well as important cross-sectional parameters, e.g. shear centre, shear and torsion stiffness of thin-walled beams (e.g. rotor blades) is possible. In order to calculate these parameters, only knowledge of the material properties and the cross-sectional geometry is necessary and not the longitudinal stretching of the rotor blade. This is possible because the three-dimensional problem can be transferred into a two-dimensional one.