Polymer journal bearings: A numerical and experimental study

In this paper, we carry out a numerical and experimental assessment of a lubricated polymer journal bearing exhibiting a viscoelastic rheology. The setup includes a metal shaft in contact with a Polyamide 6 bushing. Experiments are conducted on a rig, specifically designed to investigate bearings operating in different lubrication regimes. Tests are performed under different temperatures and loads, thus exploring how viscoelasticity influences the bearing performance. The experimental results serve as benchmarks for the numerical analysis investigating the visco-elastohydrodynamic regime. Crucially, the numerical methodology, coupling a finite difference solver with a Boundary Element formulation, assumes steady-state conditions. Despite this assumption, numerical predictions match relatively well with experimental torque data and highlight the critical role of viscoelastic hysteresis in frictional losses.