Effect of Cross-Sectional Profile of Circular Dimples on Hydrodynamic Lubrication Characteristics of Thrust Bearings

The effects of three types of dimples with different internal structures on the fluid lubrication characteristics of thrust bearings were investigated. The load-carrying capacity and the frictional torque were measured. The measurements were performed with a fixed constant film thickness. The behaviours of cavitation bubbles occurred within the dimple were observed through the rotating glass plate. Three types of internal structures of dimples were tested: cylindrical, sphere and conical. The measurement results were simulated by the Reynolds equation. As the results, the load-carrying capacity increased as the rotational speed increased. The cylindrical internal structure built up the largest pressure at the trailing edge, and consequently the largest load-carrying capacity. The frictional torque also increased with increasing the rotational speed. However, the effect of the internal structure on the frictional torque was not significant.