Hydrodynamic Behavior of Graphite Powder Slurries in Journal Bearings

Abstract

The increasingly severe requirements imposed on rotating machinery in terms of speeds, loads, and temperature impose severe operating conditions on journal bearings. An approach of using solid lubricant slurry would advance the capabilities of the existing rotating machinery related to gas turbine engines. In this study, the behavior of graphite-ethylene glycol slurry is evaluated in a hydrodynamic journal bearing operating at ambient temperatures. The evaluation is based on laboratory testing and provides some insight on the lubrication capabilities of the non-Newtonian slurry. A laboratory lest rig was designed and fabricated and the effects evaluated in terms of the difference in fluid film pressure between the pure carrier fluid and the powder slurry. It is observed that the addition of graphite increases the effective viscosity of the carrier fluid, causing not only an increase in pressure, but also an increase in fluid temperature. Presented at the 48th Annual Meeting in Calgary, Alberta, Canada May...