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On the Analysis of Rotor-Bearing-Foundation Systems

  • Katia Lucchesi Cavalca
  • Eduardo Paiva Okabe
Conference paper
Part of the IUTAM Bookseries book series (IUTAMBOOK, volume 1011)

Abstract

This work presents a methodology to analyse the influence of the foundation or supporting structure on the rotor-bearings system. A frequency response analysis of the complete system was accomplished by considering physical co-ordinates for the rotor-bearings system and principal co-ordinates for the foundation. The mathematical procedure applied a modal approach to the supporting structure, using modal parameters of generalised mass, damping ratio and natural frequency, which were calculated from the frequency response functions (FRF) of an actual structure. Convergence of the method was verified and the effect of the flexible foundation on the complete system response was analysed. A new formulation for the Mixed Co-ordinates method was presented to evaluate the influence of the supporting structure on the directional response of a rotor. An analysis of the directional frequency response function (dFRF) of the complete system was accomplished considering directional co-ordinates for the rotor-bearings system and principal co-ordinates for the foundation. These results were compared to the conventional FRF procedure.

Keywords

Flexible structures Mixed co-ordinates Modal parameters Complex modal analysis 

Notes

Acknowledgements

The authors would like to thank FAPESP and CNPq for the financial support for this work, and LAMAR team for the technical support. The authors also would like to acknowledge the invaluable contribution of professors Hans Ingo Weber and Nicoló Bachschmid to their scientific education in the rotor dynamics field.

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Laboratory of Rotating Machinery, Faculty of Mechanical EngineeringUniversity of Campinas, UNICAMPCampinasBrazil

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