Modeling of Blades as Equivalent Beams for Aeroelastic Analysis

Abstract

A procedure has been developed and tested to derive a set of one-dimensional beam properties that will duplicate the behavior of a full three-dimensional finite element model of a wind turbine blade. This allows the full features of a detailed model to be transferred to an aeroelastic code for dynamic simulation of the complete wind turbine. The process uses the NuMAD interface to generate an ANSYS® finite element model to which a set of six unit loads are applied at the tip. The displacement results are used in a series of MATLAB routines to extract the stiffness matrices of the desired beam elements. Tests have been carried out on a number of blades and the stiffness matrices incorporated into ADAMS® models of the blades and complete wind turbines.