Summary
Nonlinear vibrations of a rotating hub-beam system are analysed in the paper. A model of the beam is based on extended Euler-Bernoulli theory taking into account large beam’s displacements and related geometrical nonlinearities. The derived equations of motion take into account beam’s bending in two directions, elongation, twist, preset angle of the beam and varied angular velocity of the hub. Then, the model is successively reduced for longitudinal-flexural oscillations and next to transversal oscillations with angular velocity and the preset angle as bifurcation parameters. Externally excited oscillations of the beam and vortex induced oscillations generated by fluid flow are studied around selected resonance zones. Vortex induced oscillations are included in the model by an additional van der Pol equation coupled with the main structure.
