Analysis of Lubrication Theory for the Power Law Fluid

Abstract

A lubrication theory for the power law fluid is developed and analyzed. Only the infinite width gap is considered. Considered is flow between rigid walls of arbitrary shape under combined Couette and squeezing motion with a pressure gradient. Equations appropriate to a thin film are derived by asymptotic integration of the three-dimensional equations of fluid mechanics. Further integration of these equations yields an algebraic equation for the pressure gradient. Working out the details of the structure of this equation enables us to develop a numerical algorithm for its solution. To illustrate the theory, it is used to calculate the pressure distribution for a parabolic slider bearing and the pressure gradient and velocity distribution when the mass flux is prescribed. The latter results are compared with results obtained earlier by Dien and Elrod (1983).