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Effects of Design Conditions in Five Pad Tilting Pad Bearing on the Lateral Vibration Characteristics of Small Gas Turbine

5패드 틸팅 패드 베어링의 설계 조건 변화가 소형 가스터빈의 횡진동 특성에 미치는 영향

  • Received : 2011.05.31
  • Accepted : 2011.07.19
  • Published : 2011.08.20

Abstract

In tilting pad bearing design process, the selection of the proper configuration type of either a load-between-pad(LBP) or load-on-pad(LOP) as well as preload and pivot offset conditions is to be carefully considered. Also the bearing needs to be designed in order to be suited for the rotor-bearing system and operating condition. In this paper, it is observed that the dynamic characteristics in a five pad tilting pad bearing for the LBP and the LOP configurations are influenced by the variation of preload and pivot offset. In this context, rotor dynamic analysis of the 5 MW industrial gas turbine supported by the tilting pad bearing at the front and roller bearing at the rear is carried out based on the dynamic coefficients of the tilting pad bearing investigated. The result shows that two rigid body critical modes experience various changes according to the influence of the tilting pad bearing uniquely applied to one side of this machine. Mainly, the second critical speed, the rigid body mode of conical shape with high whirling in the tilting pad bearing, is significantly changed by preload and pivot offset regardless of the LBP and LOP configurations. And, the first critical mode, the rigid body mode of conical shape with high whirling in the roller bearing, is sensitively affected by preload applied to the LOP configuration and by its asymmetric dynamic properties.

Keywords

References

  1. Lund, J. W., 1964, Spring and Damping Coefficients for the Tilting-pad Journal Bearing, Tribology Transactions, Vol. 7, No. 4, pp. 342-352. https://doi.org/10.1080/05698196408972064
  2. Yang, S. H., Park, C. H., Kim, C. S. and Ha, H. C., 2004, Study on the Prevention of Pad Fluttering with the Variation of Preload in a Tilting Pad Journal Bearing, Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 14, No. 4, pp. 344-351. https://doi.org/10.5050/KSNVN.2004.14.4.344
  3. Delgado, A., Vannini, G., Ertas, B., Drexel, M. and Naldi, L., 2010, Identification and Prediction of Force Coefficients in a Five-pad and Four-pad Tilting Pad Bearing for Load-on-pad and Load-between-pad Configurations, Proceedings of ASME Turbo Expo 2010, Paper GT2010-23802.
  4. Nicholas, J. C. and Kirk, R. G., 1982, Four Pad Tilting Pad Bearing Design and Application for Multistage Axial Compressors, ASME Journal of Lubrication Technology, Vol. 104, No. 4, pp. 523-529. https://doi.org/10.1115/1.3253278
  5. Zeidan, F. Y. and Paquette, D. J., 1994, Application of High Speed and High Performance Fluid Film Bearings in Rotating Machinery, Proceedings of the Twenty-third Turbomachinery Symposium, TexasA&MUniversity, pp. 209-233.
  6. Schmied, J., Fedorov, A. and Grigoriev, B. S., 2010, Non-synchronous Tilting Pad Bearing Characteristics, The 8th IFToMM International Conference on Rotor Dynamics, pp. 143-148.
  7. Lee, A. S. and Kim, C. U., 2010, A Design Fitting of Journal Bearings to the LPLI Fuel Pump Application, The 8th IFToMM International Conference on Rotor Dynamics, pp. 1040-1044.
  8. Untaroiu, C. D. and Untaroiu, A., 2010, Constrained Design Optimization of Rotor-Tilting Pad Bearing Systems, ASME Journal of Engineering for Gas Turbines and Power, Vol. 132, No. 12, pp. 122502-1-122502-7. https://doi.org/10.1115/1.4001811
  9. DYNAMICS R4 User's Guide, Alfa-Tranzit Co., Ltd, Russia.
  10. ARMD User's Manual, RBTS, Inc., USA.
  11. DAMPER R3.1 Software, Alfa-Tranzit Co., Ltd, Russia.
  12. API 684, 2005, API Standard Paragraphs Rotordynamic Tutorial: Lateral Critical Speeds, Unbalance Response, Stability, Train Torsionals and Rotor Balancing, Second Edition, American Petroleum Institute, Washington, D.C.

Cited by

  1. Analysis of Tilting Pad Journal Bearings Considering Pivot Stiffness vol.30, pp.2, 2014, https://doi.org/10.9725/kstle.2014.30.2.77