Squeeze flow of a nonconstant-viscosity fluid

Squeeze flow between parallel disks of a Newtonian fluid with variable viscosity is studied using a lubrication approximation. Analytical results are obtained for circumstances in which the viscosity distribution and instantaneous plate velocity and separation are specified. Equations describing the convection of viscosity and the time dependence of the plate separation are developed, although explicit solutions could not be obtained. Our analysis is extended to include two immiscible fluid layers, each having a different but uniform viscosity. As expected, all results reduce to the classical lubrication results for constant viscosity.