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Meccanica

, Volume 26, Issue 4, pp 229–245 | Cite as

Static and dynamic behaviour of a rigid rotor on journal bearings

  • L. Della Pietra
  • E. de Rosa
  • C. Rossi
Article

Abstract

This experimental investigation concerns the ‘static’ and dynamic behaviour of a rigid balanced rotor on journal bearings. Running conditions were chosen in order to obtain relatively high eccentricity ratios near the instability threshold speeds.

The results, compared also with the theoretical predictions of some authors, have substantially shown the importance of examining the ‘static’ behaviour near the instability threshold speed to allow a correct interpretation of some aspects of the dynamic behaviour.

In order to clarify the discrepancies between the observed and the theoretically predicted dynamic behaviour, some further tests have been carried out.

Key words

Journal bearings instability rotor dynamics 

Sommario

E' stato esaminato sperimentalmente sia il comportamento “statico” che quello dinamico di un rotore rigido e bilanciato sostenuto da cuscinetti cilindrici lubrificati.

Le condizioni di funzionamento sono state scelte in modo tale che, in prossimità della soglia di instabilità, il valore del rapporto di eccentricità risultasse relativamente grande.

I risultati, confrontati anche con le indicazioni teoriche di altri autori, hanno sostanzialmente evidenziato l'importanza dell'esame del comportamento “statico” in prossimità della soglia di instabilità al fine di interpretare correttamente alcuni aspetti del fenomeno dell'instabilità.

Sono state inoltre effettuate una serie di ulteriori indagini con lo scopo di chiarire le discordanze fra il comportamento dinamico osservato e quello previsto dalla teoria.

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Copyright information

© Kluwer Academic Publishers 1991

Authors and Affiliations

  • L. Della Pietra
    • 1
  • E. de Rosa
    • 1
  • C. Rossi
    • 1
  1. 1.Dipartimento di Ingegneria Meccanica per l'EnergeticaUniversità di Napoli Federico IINapoliItaly

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