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In this paper, the stability of rotor-bearing system with
flawsis studied. The rotor-bearing system consists of rigid
disks, distributed parameter finite rotor elements, and
discrete bearings.The gonvering equations of the finite rotor
elements are developed by Hamilton's principle using Timoshenko
beam theory. And these include the effects of shaftwith flaws,
gyroscopic moments, rotatory inertia, and external loads.
Stability and dynamic stability are two topics in the present
work. Four parameters are employedto characterized the damage
zone: location, size, effect bending and shear stiffness of the
damage region. There are two kinds of load in stability
analyses, axial force and follower force. And what are the
differences of the critical loading and the behaviors after the
critical load. The damage region at the center of te shaft is a
serious effect of the system.The dynamic stability is teh other
topic. In the present analysis, the axial load is third
approximation. Numerical results show that due to the presence
damage zone, the regions of dynamic instability are shifted
closer to the dynamic load factor axis and parametric resonance
may occur at lower disturbance frequencies. Also, as the
rotational speed increases, thhe size of the regions of dynamic
instability will enlarged, and the system becomes more unstable.
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