Experimental study of starvation and flow behavior in grease-lubricated EHD contact

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

This paper describes an experimental study of starvation and flow behavior in grease-lubricated elastohydrodynamic contact. Rolling tests were conducted with four grease samples with different thickeners and base oils in a conventional ball-on-disk test rig. The EHL central film thickness was determined with SLIM, the Spacer Layer Imaging Method, and grease flow around the conjunction and the flow pattern on the track of the disk specimen were observed with CCD cameras. The grease track included some thickener deposited on the track and a corrugated fingerlike flow pattern outward from the center of the track. It was found that the flow pattern varied with grease type and test conditions, and that the average interval between fingers decreased with the entrainment speed. At higher speeds, inlet starvation occurred and the finger pattern was deformed and gradually ruptured. The speed of the finger-loss was higher than the speed at which starvation started. It was also found that the starvation speed was greater with greases having lower apparent viscosity at lower shear rate and higher apparent viscosity at high shear rate. This implied that the replenishment and entrainment of the greases depended on the viscosity characteristics of the greases.

Original languageEnglish
Pages (from-to)48-55
Number of pages8
JournalTribology Online
Volume10
Issue number1
DOIs
Publication statusPublished - 2015

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Electrohydrodynamics
Lubricating greases
Flow patterns
Viscosity
Shear deformation
Elastohydrodynamics
CCD cameras
Film thickness
Oils
Imaging techniques

All Science Journal Classification (ASJC) codes

  • Surfaces, Coatings and Films

Cite this

Experimental study of starvation and flow behavior in grease-lubricated EHD contact. / Chen, Jing; Tanaka, Hiroyoshi; Sugimura, Joichi.

In: Tribology Online, Vol. 10, No. 1, 2015, p. 48-55.

Research output: Contribution to journalArticle

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