Abstract: Several observations have been made in the Fourier spectra of high speed rotor-dynamic response of uniformly spaced frequency spikes on either side of key synchronous or subharmonic or superharmonic ...

Abstract: Subharmonic vibration refers to the response of a dynamic system to excitation at a whole-number multiple (n) of its natural frequency by vibrating asynchronously at its natural frequency, that ...

Abstract: Fluids are often introduced accidentally and trapped inside of high speed rotors. This has given concern as to the possible deleterious effects of such trapped fluids on the system’s vibration ...

Abstract: In industries like the aircraft gas turbine, trans-critical or super-critical operating speeds are quite common, and rotating machinery must be mass produced with very demanding precision in ...

Abstract: Applying the Campbell [4] criterion (for excitation of axisymmetric physical systems in proximity to turbomachinery) to an analytic model of an annular acoustic cavity, a detailed view of acoustic ...

Abstract: Subharmonic response in rotordynamics may be encountered when a rotor is operated with its rotational centerline eccentric to that of a close clearance static part, so that local contact can ...

Abstract: An analysis is made of the instability in rotating systems induced by internal damping in the rotor. The stability boundary is defined in terms of the ratio of the external damping of the ...

Abstract: The classic phenomenon of “dry friction whip,” generally associated with unlubricated journal bearings, is here reconsidered as playing an important role in the dynamic stability, and consequent ...

Abstract: A vibration incident on a gas turbine engine was noted where two major excitation frequencies were involved—an excitation synchronous with rotor rotation, associated with rotor unbalance, and an ...