A Study on the Stability Characteristics of Actively Controlled Externally Pressurized Air Journal Bearing

능동 제어되는 외부 가압 공기 베어링의 안정 특성에 관한 연구

  • Published : 2000.03.01


Results of theoretical investigations of the stability characteristics of an actively controlled externally pressurized air journal bearing are presented. Proportional control and derivative control are used for the control algorithm of active air bearing. The stability characteristics of the actively controlled bearing operating at zero steady-state eccentricity is investigated with the step jump method. The speed at onset of instability is raised for both proportional control and derivative control of bearing. Proportional control increased the stability threshold without affecting the whirl ratio. But for derivative control of bearing, stability threshold increase is accompanied by a parallel reduction of the whirl ratio. Results show active control of bearing can be adopted for the stability improvement of air journal bearing.


Air Bearing;Whirl Instability;Active Control;Step Jump Method


  1. Elrod Jr. H.G. and McCabe J.T., 1967, 'Determination of Gas-Bearing Stability by Response to a Step-Jump,' Journal of Lubrication Technology, Oct., pp. 493-498
  2. Chu T.Y., McCabe J.T. and Elrod H.G., 1968, 'Stability Consideration for a Gas-Lubricated Tilting-Pad Journal Bearing,' Journal of Lubrication Technology, Jan., pp. 162-172
  3. Fleming D.P., Cunningham R.E. and Anderson W.J., 1970, 'Zero-Load Stability of Rotating Externally Pressurized Gas-Lubricated Journal Bearings,' Journal of Lubrication Technology, April, pp. 325-334
  4. Sixsmith H., 1965, 'Applications of Gas Bearing to Miniature Expansion Turbines,' Gas Bearing Symposium at Univ. of Southampton, April
  5. Mori H., Mori A., 1971, 'A Stabilizing Method of the Externally Pressurized Gas Journal Bearings. -Succeeding Report,' Gas Bearing Symposium at Univ. of Southampton, March
  6. 김금모, 1992, '외부 가압 공기저널 베어링의 안정성 및 회전 정밀도에 관한 연구', 한국과학 기술원 박사학위논문
  7. Horikawa O. and Shimokobe A., 1990, 'An Active Air Bearing,' JSME International Journal, Series 3, Vol.33, No.l, pp. 55-60
  8. Mizumoto H., Okuno K. and Matsubara T., 1992, 'An Infinite-Stiffness Aerostatic Bearing with an Exhaust-Control Restrictor,' International Journal of JSPE, Vol.26, No.3, Sept., pp. 225-230
  9. Mori A. and Mori H., 1973, 'An Application of Pneumatic Phase Shifting to Stabilization of Externally Pressurized Journal Gas Bearing,' Journal of Lubrication Technology, Jan., pp. 33-41
  10. Tatara A., Koike H. and Iwasaki A., 1973, 'The Stability of Flexibly Supported, Externally Pressurized Gas Journal Bearings,' Bulletin of the JSME, Vol.16, No.100, pp. 1573-1579
  11. Kazimierski Z. and Jarzecki K., 1979, 'Stability Threshold of Flexibly Supported Hybrid Gas Journal Bearing,' Journal of Lubrication Technology, Vol. 101, pp. 451-457
  12. Toldl, 1967,'Bearing with a Tangential Gas Supply,' Gas Bearing Symposium at Univ. of Southamption