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Performance Predictions of Tilting Pad Journal Bearing with Ball-Socket Pivots and Comparison to Published Test Results

볼 소켓형 피봇을 갖는 틸팅 패드 저널 베어링의 성능 예측 및 기존 결과와의 비교

  • Kim, Tae Ho (School of Mechanical Engineering, Kookmin University) ;
  • Choi, Tae Gyu (Doosan Heavy industries &Construction GT SI Team)
  • 김태호 (국민대학교 기계시스템공학부) ;
  • 최태규 (두산중공업 가스터빈개발 1팀)
  • Received : 2015.06.10
  • Accepted : 2017.01.06
  • Published : 2017.04.01

Abstract

This paper predicts the rotordynamic force coefficients of tilting pad journal bearings (TPJBs) with ball-socket pivot and compares the predictions to the published test data obtained under load-between-pad (LBP) configuration. The present TPJB model considers the pivot stiffness calculated based on the Hertzian contact stress theory. Due to the compliance of the pivot, the predicted journal eccentricity agree well with the measured journal center trajectory for increasing static loads, while the early prediction without pivot model consideration underestimates it largely. The predicted pressure profile shows the significant pressure development even on the unloaded pads along the direction opposite to the loading direction. The predicted stiffness coefficients increase as the static load and the rotor speed increase. They agree excellently with test data from open literature. The predicted damping coefficients increase as the static load increases and the rotor speed decreases. The prediction underestimates the test data slightly. In general, the current predictive model including the pivot stiffness improves the accuracy of the rotordynamic performance predictions when compared to the previously published predictions.

Keywords

References

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