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http://dx.doi.org/10.9725/kstle.2014.30.2.77

Analysis of Tilting Pad Journal Bearings Considering Pivot Stiffness  

Choi, Tae Gyu (Graduate School, Dept. of Mechanics and Design, Kookmin University)
Kim, Tae Ho (School of Mechanical Systems Engineering, Kookmin University)
Publication Information
Tribology and Lubricants / v.30, no.2, 2014 , pp. 77-85 More about this Journal
Abstract
This study set out to predict the load capacity and rotordynamic coefficients of tilting-pad journal bearings, taking the pivot stiffness into account. The analysis uses rocker-back (cylindrical) and ball in socket (spherical) pivot models, both of which are based on Hertzian contact stress theory. The models ascertain the non-linear elastic deformation of the pivots according to the applied load, pivot geometry, and material properties. At present, the Reynolds equation for an isothermal, isoviscous, and incompressible fluid is used to calculate the film pressure by using the finite-element method, after which the Newton-Raphson method is used to simultaneously find the journal center location, pad angles, and pivot deflections. The bearing analysis, excluding the pivot models, is validated using predictions those are readily available in the literature. As the rotor speed increases, the predicted journal eccentricity and damping coefficients decrease, but the stiffness coefficients increase, as expected. Most importantly, the implementation of the pivot models increases the journal eccentricity but significantly decreases the stiffness and damping coefficients of the tilting-pad journal bearings.
Keywords
tilting pad journal bearing; pivot stiffness; load capacity; stiffness; damping;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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