Under repeated overrollings, the elastohydrodynamic lubrication (EHL) film thickness can be much less than the fully flooded value due to the ejection of the lubricant from the track. The ejection of the lubricant is caused by the pressure flow in the inlet, and under conditions of negligible reflow, the reduction rate is predicted by the numerical analysis with a uniform inlet film thickness. However, the degree of starvation is determined by the balance of the ejection and reflow. In the previous papers for circular contacts, the reflow is taken into account using a nonuniform inlet film thickness obtained based on the Coyne–Elrod boundary condition. In this paper, the model for circular contacts is extended to elliptical contacts, which are of more practical importance in rolling bearings. The model is verified for the inlet distance and the film thickness using a roller on disk optical test device. Numerical results are fitted to an inlet distance formula, which is a function of the initial film thickness, the fully flooded central film thickness, the capillary number, and the ellipticity ratio. The inlet distance formula can be applied to the Hamrock–Dowson formulas for the starved film thickness.

References

References
1.
Lugt
,
P. M.
,
2009
, “
A Review on Grease Lubrication in Rolling Bearings
,”
Tribol. Trans.
,
52
(
4
), pp.
470
480
.
2.
Wedeven
,
L. D.
,
Evans
,
D.
, and
Cameron
,
A.
,
1971
, “
Optical Analysis of Ball Bearing Starvation
,”
ASME J. Lubr. Technol.
,
93
(
3
), pp.
349
363
.
3.
Hamrock
,
B. J.
, and
Dowson
,
D.
,
1977
, “
Isothermal Elastohydrodynamic Lubrication of Point Contacts—Part IV: Starvation Results
,”
ASME J. Lubr. Technol.
,
99
(
1
), pp.
15
23
.
4.
Cann
,
P. M. E.
,
Damiens
,
B.
, and
Lubrecht
,
A. A.
,
2004
, “
The Transition Between Fully Flooded and Starved Regions in EHL
,”
Tribol. Int.
,
37
(
10
), pp.
859
864
.
5.
Chevalier
,
F.
,
Lubrecht
,
A. A.
,
Cann
,
P. M. E.
,
Collin
,
F.
, and
Dalmaz
,
G.
,
1998
, “
Film Thickness in Starved EHL Point Contacts
,”
ASME J. Tribol.
,
120
(
1
), pp.
126
133
.
6.
Elrod
,
H. G.
, Jr.
,
1981
, “
A Cavitation Algorithm
,”
ASME J. Lubr. Technol.
,
103
(
3
), pp.
350
354
.
7.
Wijnant
,
Y. H.
,
1998
, “
Contact Dynamics in the Field of Elastohydrodynamic Lubrication
,”
Ph.D. thesis
, University of Twente, Enschede, The Netherlands.https://research.utwente.nl/en/publications/contact-dynamics-in-the-field-of-elastohydrodynamic-lubrication
8.
Damiens
,
B.
,
Venner
,
C. H.
,
Cann
,
P. M. E.
, and
Lubrecht
,
A. A.
,
2004
, “
Starved Lubrication of Elliptical EHD Contacts
,”
ASME J. Tribol.
,
126
(
1
), pp.
105
111
.
9.
Nogi
,
T.
,
2015
, “
An Analysis of Starved EHL Point Contacts With Reflow
,”
Tribol. Online
,
10
(
1
), pp.
64
75
.
10.
Nogi
,
T.
,
2015
, “
Film Thickness and Rolling Resistance in Starved Elastohydrodynamic Lubrication of Point Contacts With Reflow
,”
ASME J. Tribol.
,
137
(
4
), p.
041502
.
11.
Coyne
,
J. C.
, and
Elrod
,
H. G.
, Jr.
,
1970
, “
Conditions for the Rupture of a Lubricating Film—Part I: Theoretical Model
,”
ASME J. Lubr. Technol.
,
92
(
3
), pp.
451
456
.
12.
Coyne
,
J. C.
, and
Elrod
,
H. G.
, Jr.
,
1971
, “
Conditions for the Rupture of a Lubricating Film—Part II: New Boundary Conditions for Reynolds Equation
,”
ASME J. Lubr. Technol.
,
93
(
1
), pp.
156
167
.
13.
Roelands
,
C. J. A.
,
1966
, “
Correlation Aspects of the Viscosity-Temperature-Pressure Relationship of Lubricating Oils
,”
Ph.D. thesis
, Delft University of Technology, Delft, The Netherlands.https://www.researchgate.net/publication/36339386_Correlation_Aspects_of_the_Viscosity-Temperature-Pressure_Relationship_of_Lubricating_Oils
14.
Dowson
,
D.
, and
Higginson
,
G. R.
,
1966
,
Elastohydrodynamic Lubrication, the Fundamentals of Roller and Gear Lubrication
,
Pergamon Press
,
Oxford, UK
.
15.
Nogi
,
T.
, and
Kato
,
T.
,
1997
, “
Influence of a Hard Surface Layer on the Limit of Elastic Contact—Part I: Analysis Using a Real Surface Model
,”
ASME J. Tribol.
,
119
(
3
), pp.
493
500
.
16.
Liu
,
S.
,
Wang
,
Q.
, and
Liu
,
G.
,
2000
, “
A Versatile Method of Discrete Convolution and FFT (DC-FFT) for Contact Analyses
,”
Wear
,
243
(
1–2
), pp.
101
111
.
17.
Dalmaz
,
G.
,
1980
, “
Formation and Separation of Thin Viscous Film in Hertzian Line Contacts
,”
ASME J. Lubr. Technol.
,
102
(
3
), pp.
466
477
.
18.
Pemberton
,
J.
, and
Cameron
,
A.
,
1976
, “
A Mechanism of Fluid Replenishment in Elastohydrodynamic Contacts
,”
Wear
,
37
(
1
), pp.
185
190
.
19.
Otsu
,
T.
,
Tanaka
,
H.
,
Izumi
,
N.
, and
Sugimura
,
J.
,
2009
, “
Effect of Surrounding Gas on Cavitation in EHL
,”
Tribol. Online
,
4
(
2
), pp.
50
54
.
20.
Lubrecht
,
A. A.
,
Venner
,
C. H.
, and
Colin
,
F.
,
2013
, “
Film Thickness Calculation in Elasto-Hydrodynamic Lubricated Line and Elliptical Contacts: The Dowson, Higginson, Hamrock Contribution
,”
Proc. Inst. Mech. Eng. Part J
,
223
(
3
), pp.
511
515
.
21.
Lugt
,
P. M.
, and
Morales-Espejel
,
G. E.
,
2011
, “
A Review of Elasto-Hydrodynamic Lubrication Theory
,”
Tribol. Trans.
,
54
(
3
), pp.
470
496
.
22.
Guangteng
,
G.
,
Cann
,
P. M. E.
, and
Spikes
,
H. A.
,
1992
, “
A Study of Parched Lubrication
,”
Wear
,
153
(
1
), pp.
91
105
.
23.
Kingsbury
,
E.
,
1985
, “
Parched Elastohydrodynamic Lubrication
,”
ASME J. Tribol.
,
107
(
2
), pp.
229
232
.
24.
Kimura
,
Y.
,
Endo
,
T.
, and
Dong
,
D.
,
2010
, “
EHL With Grease at Low Speeds
,”
Advanced Tribology
(Proceedings of CIST2008 and ITS-IFToMM2008),
J.
Luo
,
Y.
Meng
,
T.
Shao
, and
Q.
Zhao
, eds.,
Springer-Verlag
,
Berlin
, pp.
15
19
.
25.
Chen
,
J.
,
Tanaka
,
H.
, and
Sugimura
,
J.
,
2015
, “
Experimental Study of Starvation and Flow Behavior in Grease-Lubricated EHD Contact
,”
Tribol. Online
,
10
(
1
), pp.
48
55
.
26.
Sakai
,
K.
,
Tokumo
,
Y.
,
Ayame
,
Y.
,
Shitara
,
Y.
,
Tanaka
,
H.
, and
Sugimura
,
J.
,
2016
, “
Effect of Formulation of Li Greases on Their Flow and Ball Bearing Torque
,”
Tribol. Online
,
11
(
2
), pp.
168
173
.
27.
Biboulet
,
N.
, and
Houpert
,
L.
,
2010
, “
Hydrodynamic Force and Moment in Pure Rolling Lubricated Contacts—Part 2: Point Contacts
,”
Proc. Inst. Mech. Eng. Part J.
,
224
(
8
), pp.
777
787
.
You do not currently have access to this content.