• geometrically exact beam theory;
  • variational asymptotic method;
  • sectional analysis;
  • wind turbine blade;
  • CX-100


A geometrically exact beam model for simulating the structural dynamic response of the CX-100 wind turbine blade is presented. The underlying geometrically nonlinear theory is detailed, and its implementation into a finite-element code, NLBeam, developed as part of this research is outlined. The parameters used to represent the varying cross-sectional distributions of stiffness and mass are calculated consistent with the geometrically exact beam theory by using the variational asymptotic method, as developed by Hodges and Yu et al. through the commercially available code, (VABS) variational asymptotic beam sectional analysis. Code and calculation verification are documented through a systematic grid convergence study applied independently to both the cross-sectional, and static and dynamic beam simulations. An initial assessment of the model is made by comparing simulation results with experimental test data for three cases: quasistatic loading, linearized modal dynamic behavior and steady-state oscillating dynamic loads. Simulation results are shown to be in reasonable agreement with experimental data. Future improvements to the model, as well as additional experimental characterization that can benefit such modeling efforts, are outlined. Copyright © 2013 John Wiley & Sons, Ltd.