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http://dx.doi.org/10.5293/kfma.2017.20.2.063

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

Kim, Tae Ho (School of Mechanical Engineering, Kookmin University)
Choi, Tae Gyu (Doosan Heavy industries &Construction GT SI Team)
Publication Information
The KSFM Journal of Fluid Machinery / v.20, no.2, 2017 , pp. 63-68 More about this Journal
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
Damping; Load Capacity; Pivot Stiffness; Tilting Pad Journal Bearing; Stiffness;
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Times Cited By KSCI : 2  (Citation Analysis)
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