Bifurcation analysis of self-acting gas journal bearings

This paper studies the bifurcation of a rigid rotor supported by a gas film bearing. A time-dependent mathematical model for gas journal bearings is p resented. The finite differences method and the Successive Over Relation (S .O.R) method are employed to solve the Reynolds' equation. The system state trajectory, Poincare maps, power spectra, and bifurcation diagrams are use d to analyze the dynamic behavior of the rotor center in the horizontal and vertical directions tinder different operating conditions. The analysis sh ows how the existence of a complex dynamic behavior comprising periodic and subharmonic response of the rotor center, This paper shows how the dynamic behavior of this type of system varies with changes in rotor mass and rota tional velocity. The results of this study, contribute to a further underst anding of the nonlinear dynamics of gas film rotor-bearing systems.