ABSTRACT
The main problems of rotordynamics are outlined for rotors that are free or constrained, rigid or deformable, shaft-like or disk-like, for modes that involve longitudinal, torsional, or bending deformations. The basic problems of stress analysis, balancing, and alignment are briefly described, but primary emphasis is placed on the instability mechanisms that arise from small deviations from the ideal case of an undamped symmetric rotor in ideal bearings. Simplified physical explanations are given for instabilities due to rotor asymmetry, damping, and fluid-film bearings. Instabilities due to nonconservative modal coupling are illustrated for propeller-engine whirl, for whirling rotors partially filled with liquid, and for bending waves on computer memory storage disks.
