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Impact of damper seal coefficients uncertainties in rotor dynamics

  • Raphael Timbó
  • Thiago G. RittoEmail author
Technical Paper
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Abstract

Damper seals might have a great impact on rotordynamics, but the values of their coefficients are difficult to be determined and have a significant uncertainty. In the present paper, a probabilistic model is proposed to model damper seal coefficients, which are frequency dependent. A stochastic process (frequency indexed) is constructed such that modeling errors are taken into account. The impact of these uncertainties on the rotordynamic behavior of a compressor is analyzed. The deterministic seal coefficients are determined considering a bulk-flow model, and values are calculated by a compressor manufacturer based on experimental data. The results obtained show that uncertainties in these coefficients have a considerable impact on the compressor Campbell diagram, stability, and unbalance response.

Keywords

Rotor stochastic dynamics Damper seal coefficients uncertainties Stochastic Campbell diagram Model uncertainties 

Notes

Acknowledgements

The authors are grateful for the financial support of the Brazilian agencies CAPES, CNPq, and FAPERJ. This research was partially funded by FAPERJ (Grant Number E-26/201.572/2014) and CNPQ (Grant Number 400933/2016-0).

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Copyright information

© The Brazilian Society of Mechanical Sciences and Engineering 2019

Authors and Affiliations

  1. 1.Cenpes, PetrobrasRio de JaneiroBrazil
  2. 2.Mechanical Engineering DepartmentUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil

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