Finite element analysis of wind turbine blade vibrations

The article is devoted to the practical problem of computer simulation of the dynamic behaviour of horizontal axis wind turbine composite rotor blades. This type of wind turbine is the dominant design in modern wind farms, and as such its dynamics and strength characteristics should be carefully studied. For this purpose, in this paper the mechanical model of a rotor blade with a composite skin possessing a stiffener was developed and implemented as a finite element model in ABAQUS. On the basis of this computer model, modal analysis of turbine blade vibrations was performed and benchmark cases for the dynamic response were investigated. The response of the system subjected to a uniform underneath pressure was studied, and the root reaction force and blade tip displacement time histories were obtained from the numerical calculations conducted

Approximate mode-based simulation of composite wind turbine blade vibrations using a simplified beam model

It is well-known that lower modes of vibration are responsible for a high percentage of the dynamic response. In this paper, the task of simulation of the dynamic response of the composite wind turbine blade on the basis numerical realisation of a developed low dimensional beam type model is considered. From the governing system of differential-algebraic equation of the simplified beam type model of the blade, and using the mode superposition approximation, the system of linear ordinary differential equations with respect to the coefficient functions of the modal representation was obtained. The developed program codes allow to simulate low frequency bending vibrations of wind turbine blades under different steady-state and transient loadings. The comparison of the simulation results obtained by the proposed simplified blade model with the results of the direct Finite Element Method (FEM) simulation shows their close agreement, which confirms the adequacy of the developed model and its mode-based approximation to the level of the requirements necessary in engineering practice. The presented approach to the creating low-dimensional simplified models of slender structures can therefore be useful in different fields of aerospace, civil, mechanical, and transport engineering