Inlet Dimple: Numerical Simulation of Boundary Slip Effect Using Circular Model

Abstract

Circular model, assuming limiting shear stress as an intrinsic property of the lubricant, was incorporated into Reynolds Equation to simulate slip effect from elastohydrodynamic lubrication (EHL) to hydrodynamic lubrication (HL) regimes. With speed increasing, coefficient of friction shows an abnormal wave in Stribeck curve, together with an inlet dimple appears on the contact profile. Multi-beam interferometry strategy was introduced to form pseudo-interferogram. Inlet dimple is obtained in pseudo-interferogram, which is similar to that observed in experiments. Effects of load, speed, reduced modulus of elasticity and slide-roll ratio were examined respectively. Slip is verified to be able to produce abnormal contact profile and friction variation. In engineering applications, reasonable slip effects can therefore be considered capable of reducing friction.

Keywords: Stribeck curve, boundary slip, Circular model, dimple