Fluid Film Lubrication with Nonlinear Four-Element Viscoelastic Fluids (4th Report, Finite-Width Journal Bearings)

In order to establish an analytical procedure for viscoelastic fluid film lubrication, a modified Reynolds equation for finite-width bearings based on a nonlinear four-element model was derived in the first paper. In the second and third papers the effects of nonlinear viscoelastic characteristics on the film pressure of parallel circular bearings were discussed by comparing the theories with the experiments. In this paper, by applying the modified Reynolds equation to a finite-width journal bearing which is vibrated sinusoidally in one direction, the numerical procedure for finite-width bearings is clarified and the bearing performance is calculated theoretically. In addition, experiments of finite-width journal bearings using lubricating oils containing high molecular-weight polymers as viscoelastic fluids are carried out, and good agreement is shown between the experimental results and the theoretical predictions.