Start-up Dynamic Analysis of a Rotor Supported by Fluid Film Bearings

摘要: Start-up and steady-state dynamics of a rotor supported by fluid film bearings is studied. A assumed as thin disk located on the middle an elastic shaft, which bearings. The journal bearing selected short-plain type it represented direct cross-coupling stiffness damping coefficients, are angular speed dependent. An electric motor accelerates its controlled second order transfer function. Simulation results show that for certain range system becomes unstable. instability region has lower upper limits. affect rotor, equivalent ratios natural frequencies in x y directions differ cause 2x-critical super-harmonic oscillations. Before limit unstable region, whirl equal to one-half critical speed. After always one In this high amplitude oscillations appear.