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http://dx.doi.org/10.9725/kstle.2016.32.1.1

Thermal Deformation Induced Preload Changein the Tilting Pad Journal Bearing  

Suh, Junho (Technical Regulation Team, Korea Railroad Research Institute)
Hwang, Cheolho (Dept. of Mechanical Engineering, Hannam University)
Publication Information
Tribology and Lubricants / v.32, no.1, 2016 , pp. 1-8 More about this Journal
Abstract
This paper focuses on the thermal deformation induced preload change in the tilting pad journal bearing, using a three-dimensional (3D) thermo-hydro-dynamic (THD) approach. Preload is considered as a critical factor in designing the tilting pad journal bearing. The initial preload measured under nil external load and nil thermal gradient is influenced by two factors, namely, the thermal deformation and elastic deformation. Thermal deformation is due to a temperature distribution in the bearing pads, whereas the elastic deformation is due to fluid forces acting on the pads. This study focuses on the changes induced in preload and film clearance due to thermal deformation. The generalized Reynolds equation is used to evaluate the force of the fluid and the 3D energy equation is used to calculate the temperature of the lubricant. The abovementioned equations are combined by establishing a relationship between viscosity and temperature. The heat transfer within the bearing pads, the lubricant, and the spinning journal is calculated using the heat flux boundary condition. The 3D Finite Element Method (FEM) is used in modeling the (1) heat conduction in the spinning journal and bearing pads, (2) thermal gradient induced thermal distortion of the spinning journal and pads, and (3) viscous shearing, and heat conduction and convection in a thin film. This evaluation method has an increased fidelity, and it can prove to be a cost-effective tool that can be used by designers to predict the dynamic behavior of a bearing.
Keywords
energy equation; preload; Reynolds equation; tilting pad journal bearing; thermal deformation;
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Times Cited By KSCI : 1  (Citation Analysis)
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