Stability and Bifurcation of Flexible Rotor System with Hydrodynamic Bearing Supports

Nonlinear dynamic behaviors of hydrodynamic bearing-flexible rotor system are analyzed. A local iteration method consisting of improved Wilson-thetas method, predictor-corrector mechanism and Newton-Raphson method is proposed to calculate nonlinear dynamic responses. By the proposed method, the iterations are only executed on nonlinear degrees of freedom. The stability and bifurcation type of the periodic responses are determined by Floquet theory. The numerical results reveal periodic, quasi-periodic, co-existing, jump solutions of rich and complex nonlinear behaviors of the system, and show that the proposed methods not only save computing cost but also have high precision.