Elastohydrodynamic Behavior of Rolling Elliptical Contacts: Part I: Pressure and Temperature Distributions

Abstract

A two disk machine with a spherical disk mating a plain cylindrical one has been constructed to operate at different elliptical contact situations under various loads and rolling to sliding speeds. The disks axes can skew relative to each other so that various elliptical contacts could be tested. By the aid of specially modified evaporated transducers (Manganin band for pressure measurements and platinum band for temperature measurements), the elastohydrodynamic (EHD) pressure and temperature distributions could be accurately traced. Results, herein presented, confirmed that within the contact zone, the pressure distribution exhibits an almost Hertzian shape but with a second pressure peak (spike) near the trailing (exit) end of the oil film. The temperature has proven to display a distribution analogous to that described by the generated EHD pressure.

Thin films in elastohydrodynamic lubrication: The contribution of experiment

“…The 1980s continued the application of optical interferometry to a range of practical problems, including the influence on film thickness of slide±roll ratio [32] and the behaviour of suspended solid particles in EHD contacts [33,34]. Microtransducers, although they had been used since the 1960s [35], also began to become widely employed in the 1980s to produce film thickness, temperature and pressure profiles across EHD contacts [36,37]. The ability to obtain film thickness profiles greatly strengthened the capacitance technique for measuring film thickness, since it removed some of the difficulties of interpreting average capacitance measurements across contacts.…”