Bifurcation and Chaos Characteristics of the Responses of an Over-hung Rotor System with Dual Disks

The dynamic equations of an over hung rotor system with two disks excited by rub impact force were derived and a new formula for calculating rub impact force was introduced by using Coulomb friction model. The rub impact phenomenon and the nonlinear bifurcation and chaos response of the rotor system were analyzed. The influence of system parameters on the bifurcation of system response was studied and the route for system response entering chaos was given. It is found that there are two routes for the system response entering into chaos: one is from quasi\|period and the other is from intermittence. The influence of support positions on the system response was also studied. The results indicate that the decrease of the distance between support 1 and disk 1 or between support 2 and disk 2 will make the system unstable. The bigger the stiffness and the unbalance parameters of disk 1 are, the easier for the system to become unstable.