Vibration Problems With High-Speed Turbomachinery

The paper presents several examples of vibrational problems recently experienced by several turbine manufacturers. These problems include stability, system critical speeds, rotor response to unbalance, and balancing of high-speed compressors and turbines. The effects of fluid-film bearings and seals, bearing pedestals, and other parts of support structure on rotor response and critical speeds are discussed. The effects of rotor stiffness, mass, and inertia distribution are presented. The paper gives a comparison between theory and practice and provides guidelines to machinery designers.