Dynamic bifurcation and stability analysis for nonlinear rotor bearing system

The rotor-bearing system was investigated by using the stability and bifurcation theory for nonlinear dynamic system and the database method. Both the double-period bifurcation points and the global diagrams of the system were acquired. The development process from synchronous motion to double-period motion and to chaotic motion was illustrated for the system. The Floquet theory was chosen for the analysis of stability of periodic motions. Some journal center locus and Poincare maps at different speeds were given. The results show that there exist abundant dynamic behaviors such as 1-T periodic motion, double-period motion, K-T periodic motion, and chaotic motions within certain parameters. When the leading Floquet multiplier crosses the unit circle at (-1,0), the period doubling bifurcation occurs.