Journal of Failure Analysis and Prevention

, Volume 6, Issue 4, pp 73–82 | Cite as

Failure analysis of a misaligned and unbalanced flexible rotor

  • M. Attia Hili
  • T. Fakhfakh
  • M. Haddar
Peer Reviewed Articles


Shaft misalignment and rotor unbalance are major concerns in rotating machinery. In order to understand the dynamic characteristics of these machinery faults, a model of a complete motor flexible-coupling rotor system capable of describing these failures was developed. Generalized system equations of motion for a rotor under misalignment and unbalance conditions were derived using the finite element method. A spectral method was developed for resolving the equation of motion. This allows one to obtain and analyze the dynamic response and consequently to identify misalignment and unbalance faults.


dynamic response misalignment spectral method spinning system unbalance 


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Copyright information

© ASM International 2006

Authors and Affiliations

  • M. Attia Hili
    • 1
  • T. Fakhfakh
    • 1
  • M. Haddar
    • 1
  1. 1.Mechanical Engineering Department-National School of EngineersMechanics Modelling and Production Research UnitSfaxTunisia

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