Geometric Nonlinear Analysis of Composite Beams Using Wiener-Milenkovic Parameters

摘要

This paper presents a geometric nonlinear analysis of composite beams, and includes static, dynamic, and eigenvalue analyses. The increase in size and flexibility of engineering components such as wind turbine blades causes geometric nonlinearity to play an increasingly significant role in structural analysis. The Geometric Exact Beam Theory (GEBT), pioneered by Reissner and extended by Hodges, is adopted as the foundation for this work. Special emphasis is placed on the vectorial parameterization of finite rotation, which is a fundamental aspect in the geometric nonlinear formulation. This method is introduced based on the Euler's rotation theorem and the property of rotation operation: length preservation of the rotated vector. The GEBT is then implemented with the Wiener-Milenkovic parameters using a mixed formulation. Several numerical examples are studied based on the derived theory and the results are compared with analytical solutions and those available in the literature. Analysis of a realistic composite wind turbine blade is provided to show the capability of the present model for generalized composite slender structures. The analysis concludes that the proposed model can be used as a beam tool in a multibody framework whose valid range of rotation is up to 2_π.