Mass Conserving Elastohydrodynamic Lubrication Model of Engine Bearings Having Regular Striations

Regular striations exist on bearing surfaces due to machining. In this study, a mass conserving elastohydrodynamic lubrication model of an engine journal bearing having regular striations on a surface has been developed for analyzing lubrication characteristics. The model is based on a modified Elrod's cavitation algorithm and a theory of surface roughness. The cross sectional shape of the regular striations is formed into by isosceles trapeziums. The model was applied to a con-rod big-end bearing and the effect of striations on friction power loss was calculated. Friction power loss of the bearing with circumferential striations is lower than that of the bearing with transversal striations and is as much as that of the bearing with a smooth surface. The calculated results of the model were compared with those of an elastohydrodynamic lubrication model without cavitation algorithm. Though the calculated values are slightly different, the same tendencies are obtained.