Nonlinear coupling modeling and dynamics analysis of rotating flexible beams with stretching deformation effect

Dynamic coupling modeling and analysis of rotating beams based on the nonlinear Green-Lagrangian strain are introduced in this work. With the reservation of the axial nonlinear strain, there are more coupling terms for axial and transverse deformations. The discretized dynamic governing equations are obtained by using the finite element method and Lagrange’s equations of the second kind. Time responses are conducted to compare the proposed model with other previous models. The stretching deformation due to rotating motion is observed and calculated by special formulations under dynamic equilibrium. The stretching deformation and the change of the associated equilibrium position are taken into account to analyze the free vibration and frequency response of the rotating beams. Analytical and numerical comparisons show that the proposed model can provide reliable results, while the previous models may lead to imprecise results, especially in high-speed conditions.