This paper is devoted to the understanding of the flow characteristics of a powder lubricant. An accurate and realistic model is introduced to investigate the mechanism of powder lubrication sheared between two infinitely wide parallel plates. In this theory, the solid volume fraction, v, together with flow velocity and granular temperature are directly obtained from a set of complete governing equations (mass, momentum and pseudo-energy conservation equations). The boundary conditions take into account the effect of slip velocity and the wall surface roughness. A set of parametric simulation results is presented. It is shown that viscous dissipation plays an important role in the pseudo-energy equation. [S0742-4787(00)01901-9]

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