Vibration Analysis for Turbomachinery

Abstract

Turbomachinery requires a higher level of vibration analysis than general purpose machinery. This includes identifying natural frequencies or modes of a system to determine if a potential resonance occurs. The complexity of turbomachinery requires this higher level of vibration analysis, which includes understanding the importance of transient data (i.e. start-up/shutdown), the role of rotordynamics, advanced signal processing, and many other concepts. Likewise, a different array of plotting configurations is required to extract the necessary data for an accurate assessment of the machinery (i.e. Bode, Nyquist, Waterfall, Cascade, shaft centerline, and time waveform plots). An essential part of machinery troubleshooting is using as measured vibration to “tune” a rotordynamic model so that it can accurately predict both stability and forced response changes. This will allow the engineer to make design changes to the equipment to potentially reduce the vibration to an acceptable level.