Elastohydrodynamic traction and film thickness at high speeds
File(s)
Published version
OA Location
Author(s)
Maclaren, Alexander
Kadiric, Amir
Type
Journal Article
Abstract
A renewed interest in elastohydrodynamic lubrication (EHL) phenomena at high speeds, for which thermal effects strongly influence both traction and film thickness, has grown out of the challenges presented by high-speed geared transmissions in electric vehicles. This study uses a new ball-on-disc set-up employing the well-known ultra-thin-film interferometry technique to simultaneously measure EHL film thickness and traction at entrainment speeds up to 20 m/s and slide-roll ratios up to 100%. The effect of fluid composition is examined for Group I, II and III mineral oils, for two polyalphaolefins in Group IV, and for the traction fluid Santotrac 50. The effect of viscosity in the range 4–180 mPa.s is investigated by varying bulk fluid temperature. At high speeds, both film thickness and traction are considerably lower than predicted by conventional EHL theory. The contact is seen to be fully-flooded for all conditions tested. The widely-used thermal EHL correction of Gupta is shown to overcorrect for the film thickness reduction even at modest SRRs. Finally, the influence of the sliding direction on traction and film thickness is discussed for this set-up, and a thermal model is proposed to explain the observed behaviour.
Date Issued
2024-09-01
Date Acceptance
2024-07-09
Citation
Tribology Letters, 2024, 72 (3)
ISSN
1023-8883
Publisher
Springer
Journal / Book Title
Tribology Letters
Volume
72
Issue
3
Copyright Statement
© The Author(s) 2024, corrected publication 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
License URL
Identifier
10.1007/s11249-024-01894-w
Subjects
BEHAVIOR
CONTACTS
EHL
EHL film geometry
Engineering
Engineering, Chemical
Engineering, Mechanical
LINE
LUBRICANT FILMS
Science & Technology
Technology
TEMPERATURE
Thermal effects in EHL
Traction
Publication Status
Published
Article Number
92
Date Publish Online
2024-07-18