Fluid film lubrication with nonlinear four-element viscoelastic fluids (finite-width journal bearings and parallel circular bearings in normal approach).

A model Reynolds equation for nonlinear viscoelastic fluids based on a nonlinear four element model was derived, and the effects of viscoelastic behaviour on the performance of parallel circular squeeze bearings oscillated sinusoidally was clarified by comparing the theoretical results with the experimental ones, in the previous paper. This paper presents two applications of the modified Reynolds equation to fluid film lubrication problems. Firstly, by applying the modified Reynolds equation to a finite width journal bearing which is oscillated sinusoidially, the analytical procedure for viscoelastic lubrication problems under three dimensional flows of lubricants is clarified, and good agreement is shown between the experimental results and the theoretical predictions based on the four element model. Secondly, to clarify the effects of viscoelastic behaviour on the performance of parallel circular bearings under irregular squeeze motion, theoretical and experimental studies of parallel circular plates in normal approach are shown.