Nonlinear dynamics and bifurcation for a Jeffcott rotor with seal aerodynamic excitations

The nonlinear vibration and bifurcation characteristics of a Jeffcott rotor aerodynamically excited by gas seals are presented in this paper. The Muszynska's model is adopted to express the seal forces as the nonlinear function of rotor displacement, velocity and acceleration. The Runge-Kutta method is used to obtain the displacement and bifurcation diagrams with parameters of the pressure drop and the length of the seal. Various period-multiple bifurcations are found showing complexity of the rotor's motion under the aerodynamic excitation of the seal