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Cracked Continuous Rotors Vibrating on Nonlinear Bearings

  • C. A. PapadopoulosEmail author
  • A. C. Chasalevris
  • P. G. Nikolakopoulos
Conference paper
Part of the IUTAM Bookseries book series (IUTAMBOOK, volume 1011)

Abstract

The dynamic behavior of cracked rotors continues to attract the interest of both designers and maintenance engineers. In this work, a continuum mechanics approach is used to simulate rotor vibration. The case of the cracked continuous rotor is examined by introducing suitable complex boundary conditions. The shaft rotates on two journal bearings that are simulated as forces acting on it and the boundary conditions are expressed accordingly. When the angular velocity passes through critical speeds, these forces become highly nonlinear. Identifications of cracking and wear of the bearing are separately investigated. The current challenge for design engineers is to provide lighter, quieter, more efficient, compact, and stable, as well as less expensive and ecologically friendly, rotating machines, operating even in severe conditions. In other words, new targets must be seen from the following three points of view: (a) analysis and design, (b) new material technology, and (c) new production techniques.

Keywords

Rotor Shaft Crack Bearing Wear Nonlinear 

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • C. A. Papadopoulos
    • 1
    Email author
  • A. C. Chasalevris
    • 1
  • P. G. Nikolakopoulos
    • 1
  1. 1.Department of Mechanical Engineering & AeronauticsUniversity of PatrasPatrasGreece

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