Experimental Investigation into Enhancement of Lubricant Replenishment Induce by Angled Entrainment

doi:10.3901/JME.2020.17.225

Abstract

Abstract: The enhancement of lubricant replenishment and film formation induced by angled entrainment effects are investigated. Using ball-on-disc optical apparatus, angled entrainment is formed by adjusting the motion direction of steel ball which could induce different angles between entrainment and sliding velocities. Comparing with the situations of entrainment in the same directions under fixed amount of oil feeding, it is found that the inlet lubricant supplying conditions are significantly improved, characterized by the appearance of a remarkable inlet oil reservoir. This reservoir pushes the film thickness approach the fully flooded states, which is quite different with the situations of traditional starved contacts. The patterns of inlet reservoir varying with angles, velocities, oil feeding amounts and viscosities, as well as the asymmetry film shapes are investigated. The main mechanisms resulting in the inlet oil reservoir was the delivery of overlapped side bands into the inlet conjunctions. The effect of thermal wedge viscosity is response for the distorted film shape. The reduction in film thickness with angle increas ing is attributed to the inlet shear heating effect, side leakage, inflow of heat from contact zone into inlet zone and shear thinning effect. The observations suggest the tradition boundaries under starvation are limited to be applied to present situations.

Key words: angled entrainment, lubricant replenishment, inlet oil reservoir, starvation, interferometry

CLC Number:

TH117

LI Xinming, ZHOU Guangyun, GUO Feng, ZHANG Jianjun. Experimental Investigation into Enhancement of Lubricant Replenishment Induce by Angled Entrainment[J]. Journal of Mechanical Engineering, 2020, 56(17): 225-232.

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