Experimental investigation of the influence of surface structures on hydrodynamic fluid film thickness and contact temperatures in sliding contacts

The hydrodynamic lubrication performance of face seals with T-shaped surface structures and conventional face seals is investigated. This study examines how surface structures influence fluid film thickness and contact temperatures. Fluid film thickness is measured using the laser-induced fluorescence method, and contact temperatures are measured using infrared thermography. Subsequently, the measured film thicknesses and contact temperatures for both structured and conventional seals are compared. It is shown that cavitation forms in the divergent regions of the surface structures while in the convergent regions, fluid pressure increases. This asymmetric pressure distribution results in a net positive fluid lifting force which affects both fluid film thickness and contact temperatures. Consequently, higher film thicknesses and lower contact temperatures are observed for the structured seals.