• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.77-78
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• 2002

A regression formula including the inlet film thickness as the parameter for the starvation factor in EHL condition is obtained by numerical analysis with Elord‘s cavitation algorithm. In addition, an apparatus for starved film thickness measurement by use of the white light interferometry is developed in order to verify the proposed regression formula. From observation results by this apparatus, the proposed regression formula can predict the reduction of central film thickness caused by starvation in a ball-plate contact with an uncertainty up to 10%

• Tribology and Lubricants
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• v.26 no.4
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• pp.209-218
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• 2010

In this study, the effect of dimensions and location of oil grooves on the static performance of a cylindrical journal bearing is analyzed numerically. Axial length, circumferential length and location of oil grooves are considered as parameters. Cavitation occurs within the diverging region of a journal bearing. The distribution of cavitation region where cavitation occurs varies with dimensions and location of oil grooves and affects the performance of a journal bearing. Elrod's cavitation algorithm which implements JFO boundary conditions based on the principle of mass conservation at the interfaces between cavitation and full film region is adopted in order to consider the effect of cavitation. The result shows that parameters, especially location of oil grooves have a great effect on the static performance of a journal bearing.

• Tribology and Lubricants
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• v.32 no.1
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• pp.24-31
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• 2016

In this paper hydrodynamic lubrication analysis is carried out to investigate the effects of groove location on the lubrication performance of a piston and cylinder system in a linear compressor. The rectangle shaped grooves having a constant groove depth and width are applied on the lubrication area of the piston. The Universal Reynolds equation is used to calculate the oil film pressure, and the Elrod algorithm with the finite different method is used to solve the governing equation. The JFO boundary condition is applied to predict cavitation regions. Transient analysis for different locations of the grooves on the piston is carried out using the typical operating condition of the linear compressor in order to estimate the variations of frictional power losses and minimum film thicknesses. When the grooves are applied on the lubrication area, both the frictional power loss and the minimum film thickness decrease. The frictional power loss can be reduced effectively, while maintaining a minimum film thickness to enable the piston operation without direct contact with the cylinder surface, by means of choosing a proper location of the grooves. The optimum location of the grooves to improve a lubrication performance depends on the operation condition or the system requirements specification.