Graphical Abstract Figure
Graphical Abstract Figure
Close modal

Abstract

In many mechanical systems, elastohydrodynamic lubrication (EHL) is apparent in the interfaces between rolling/sliding parts. Even at small slide-to-roll ratios, detailed knowledge about the oil film thickness and the traction exerted by the highly pressurized lubricant is crucial for the efficiency and reliability of such systems. In this study, we explore the impact of surface velocity direction and contact ellipticity on traction characteristics within EHL through numerical simulations using an elliptical EHL contact solver based on a fully coupled finite element approach. We present a novel master curve that correlates the traction coefficient slope with the lubricant entrainment direction and ellipticity, for elliptical EHL contacts in the piezoviscous elastic (PE) regime. We demonstrate that the master curve shows a maximum relative difference of less than 3.2% to the numerical simulation results, proving its efficacy. This curve is particularly beneficial for multibody-dynamics models, providing a reliable tool for predicting frictional forces in systems where elliptical EHL contacts, operating within the PE regime at low SRR, are prevalent.

References

1.
Habchi
,
W.
,
Bair
,
S.
, and
Vergne
,
P.
,
2013
, “
On Friction Regimes in Quantitative Elastohydrodynamics
,”
Tribol. Int.
,
58
, pp.
107
117
.
2.
Hamrock
,
B. J.
, and
Dowson
,
D.
,
1981
,
Ball Bearing Lubrication
,
John Wiley & Sons
,
New York
.
3.
Chittenden
,
R. J.
,
Dowson
,
D.
,
Dunn
,
J. F.
, and
Taylor
,
C. M.
,
1985
, “
A Theoretical Analysis of the Isothermal Elastohydrodynamic Lubrication of Concentrated Contacts I. Direction of Lubricant Entrainment Coincident With the Major Axis of the Hertzian Contact Ellipse
,”
Proc. R. Soc. A
,
397
, pp.
245
269
. https://www.jstor.org/stable/2397859
4.
Chittenden
,
R. J.
,
Dowson
,
D.
,
Dunn
,
J. F.
, and
Taylor
,
C. M.
,
1985
, “
A Theoretical Analysis of the Isothermal Elastohydrodynamic Lubrication of Concentrated Contacts II. General Case, With Lubricant Entrainment Along Either Principal Axis of the Hertzian Contact Ellipse or at Some Intermediate Angle
,”
Proc. R. Soc. A
,
387
(
1813
), pp.
271
294
.
5.
Chittenden
,
R. J.
,
Dowson
,
D.
, and
Taylor
,
C. M.
,
1987
, “
The Estimation of Minimum Film Thickness in the Design of Concentrated Contacts
,”
Proceedings of the IMechE Conference on Tribology-Friction Lubrication and Wear-Fifty Years On
,
Queen Elizabeth II Conference Centre, London
.
6.
Chittenden
,
R. J.
,
Dowson
,
D.
, and
Taylor
,
C. M.
,
1987
, “
Paper VIII(ii) the Lubrication of Elliptical Conjunctions in the Isoviscouselastic Regime With Entrainment Directed Along Either Principal Axis
,”
Tribol. Ser.
,
11
, pp.
247
260
.
7.
Nijenbanning
,
G.
,
Venner
,
C. H.
, and
Moes
,
H.
,
1994
, “
Film Thickness in Elastohydrodynamically Lubricated Elliptic Contacts
,”
Wear
,
176
(
2
), pp.
217
229
.
8.
Venner
,
C. H.
, and
Lubrecht
,
A. A.
,
2010
, “
Revisiting Film Thickness in Slender Elasto-Hydrodynamically Lubricated Contacts
,”
Proc. Inst. Mech. Eng. Part C J. Mech. Eng. Sci. 1989–1996
,
203–210
(
12
), pp.
2549
2558
.
9.
Masjedi
,
M.
, and
Khonsari
,
M.
,
2014
, “
On the Effect of Surface Roughness in Point-Contact EHL: Formulas for Film Thickness and Asperity Load
,”
Tribol. Int.
,
82
, pp.
228
244
.
10.
Pu
,
W.
,
Zhu
,
D.
, and
Wang
,
J.
,
2017
, “
A Starved Mixed EHL Model for the Prediction of Lubrication Performance, Friction and Flash Temperature With Arbitrary Entrainment Angle
,”
ASME J. Tribol.
,
140
(
3
), p.
031501
.
11.
Wheeler
,
J. D.
,
Fillot
,
N.
,
Vergne
,
P.
,
Philippon
,
D.
, and
Morales-Espejel
,
E. G.
,
2016
, “
On the Crucial Role of Ellipticity on Elastohydrodynamic Film Thickness and Friction
,”
Proc. Inst. Mech. Eng. Part J J. Eng. Tribol.
,
230
(
12
), p.
1503
1515
.
12.
Katyal
,
P.
, and
Kumar
,
P.
,
2020
, “
Effect of Arbitrary Entrainment Angle in Elastohydrodynamic Lubrication Elliptical and Circular Contacts
,”
Proc. Inst. Mech. Eng. Part J J. Eng. Tribol.
,
234
(
3
), pp.
424
434
.
13.
Higashitani
,
Y.
,
Kawabata
,
S.
,
Björling
,
M.
, and
Almqvist
,
A.
,
2023
, “Optimization of the Computational Domain for EHL Point Contacts,” Preprint (Version 1) Available at Research Square.
14.
Habchi
,
W.
,
Eyheramendy
,
D.
,
Vergne
,
P.
, and
Morales-Espejel
,
G.
,
2008
, “
A Full-System Approach of the Elastohydrodynamic Line/Point Contact Problem
,”
ASME J. Tribol.
,
130
(
2
), p.
021501
.
15.
Wedeven
,
L. D.
,
Evans
,
D.
, and
Cameron
,
A.
,
1971
, “
Optical Analysis of Ball Bearing Starvation
,”
ASME J. Lubr. Technol.
,
93
(
3
), pp.
349
361
.
16.
Hultqvist
,
T.
,
2020
, “
Transient Elastohydrodynamic Lubrication: Effects of Geometry, Surface Roughness, Temperature, and Plastic Deformation
,”
Ph.D. thesis
,
Luleå University of Technology
,
Luleå, Sweden
.
17.
Sahlin
,
F.
,
Almqvist
,
A.
,
Larsson
,
R.
, and
Glavatskih
,
S.
,
2007
, “
A Cavitation Algorithm for Arbitrary Lubricant Compressibility
,”
Tribol. Int.
,
40
(
8
), pp.
1294
1300
.
18.
Roelands
,
C. J. A.
,
1966
, “
Correlational Aspects of the Viscosity–Temperature–Pressure Relationship of Lubricating Oils
,”
Doctoral thesis
,
Civil Engineering and Geosciences, Delft University of Technology
,
Mijnbouwkunde
.
19.
Venner
,
C. H.
, and
Lubrecht
,
A. A.
,
2000
,
Multilevel Methods in Lubrication
,
Elsevier Science
,
Amsterdam
.
20.
Moes
,
H.
,
2000
,
Lubrication and Beyond
,
University of Twente
,
Enschede
.
You do not currently have access to this content.