Determination of friction coefficient for water-lubricated journal bearing considering rough surface EHL contacts

This work aims to study the tribological performance of the water-lubricated journal bearings by developing an EHL model considering non-Gaussian roughness and cavitation. An elastohydrodynamic lubrication (EHL) model is established by solving the Reynolds equation, elastic deformation and film thickness equations in a coupling manner by using the finite difference method with a successive over-relaxation scheme. The non-Gaussian flow factors and cavitation factors are incorporated in the Reynolds equation to tackle the roughness and non-Gaussian roughness effects. The result shows that the coefficient of friction increases with an increase in skewness. A significantly increase in the minimum film thickness is observed for a surface having high negative skewness. The friction coefficient decreases with an increase in the L/D ratio.