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Torsional Vibration Analysis of Rotors–Part I

D. B. Kulkarni

Abstract


The vibratory behavior of any coupled rotors need to be analyzed during design phase in order to ensure a trouble free smooth operation. The lateral (flexural) vibrations are comparatively easier to analyze, predict, measure and correct if required. On the other hand torsional vibrations are relatively difficult to analyze and predict, but quite tough to measure and very expansive to correct if required. This makes the torsional analysis of the rotating system a must for rotors with high inertia having flywheels, systems with intermediate gearbox (for speed increase or decrease) and branched systems. The branched systems are more complex as the different segments rotate at different speeds. An approach to coupled rotor system is presented in this paper. A software is developed based on Holzer’s method to determine the frequencies and the mode shapes. Numerical examples are presented to establish the software. The results of the software are compared with published literature.

Keywords


vibrations, torsional analysis, rotors, gearbox, flywheels

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References


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