Experimental Observation of Cavitation Under Point and Elliptical Contacts with Fluid Film Lubrication

Cavitation in fluid film lubrication was experimentally observed by optical interferometry under point and elliptical contacts. Fern leaf cavities and stripe-shaped cavities presented themselves in pure rolling, while string-shaped cavities and sheet cavitation were found in disk simple sliding. Cavitation zone moves downstream toward the outlet of the contact zone with increasing entrainment speed in pure rolling, whereas it is just the reverse in disk simple sliding. Increasing applied load increases threshold speed of occurrence of sheet cavitation. Under elliptical contacts, this threshold speed increases with increasing included angle between the entrainment direction and the minor axis of the elliptical contact zone; the included angle mentioned above markedly affects the position and shape of cavitation zone.