The nature of real shear-thinning in elastohydrodynamic contacts is well-known from both experimental measurement and nonequilibrium molecular dynamics to follow a power-law. Shear-thinning will affect the film thickness when the Newtonian limit is low enough to occur in the inlet zone (less than about 1 MPa shear stress). Then kinetic theory tells us that film thinning should occur for molecular weight greater than 2000 kg/kmol. We present a review of generalized Newtonian models, flow curves for real lubricants and comparison of calculated and measured film thickness. The calculations utilize measurable liquid behavior, in contrast to most previous work.

Issue Section:
Technical Papers
Keywords:
film flow, shear flow, liquid films, elasticity, lubrication, flow simulation, viscosity, rheology
Topics:
Film thickness, Molecular weight, Shear (Mechanics), Viscosity, Shear stress, Flow (Dynamics), Fluids, Pressure
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