Hydrodynamic Lubrication of Journal Bearings by Pseudo-Plastic Lubricants : Part 1, Theoretical Studies

Abstract

It is well known that lubricating oils, with viscosity index improver added, exhibit the same behavior as pseudo-plastic fluids. Though the theory of hydrodynamic lubrication flow for non-Newtonian fluids of this type is important, it has not been developed thoroughly due to difficulties involved in analytical and experimental treatments .The modified Reynolds equation introducing a "nonlinear factor" quantity is presented in this paper. This equation is solved by the perturbation method in the case of a small nonlinear factor and by a digital computer in the case of a large one. Applying this theory to journal bearings, the relation between the nonlinearity of lubricants and the performance of bearings, such as film pressure, load capacity, frictional force and attitude angle, can be clarified.