This study presents a generalized model of mixed elastohydrodynamic lubrication, in which the dimensional Reynolds equation is discretized according to a modified differential scheme based on the full analysis of the pressure balance within the lubrication region. The model is capable of a wide range of lubrication regimes from fully hydrodynamic down to boundary lubrication, and both the steady-state and the time-dependent conditions can be considered. A simplified computational procedure is proposed for elliptical contacts without the ellipticity parameters specified. The evolution of lubrication behavior at startup and shutdown conditions is investigated and the transient effect of surface waviness is discussed. The model application is then extended to contacts of multilayered materials, and the effects of the layer stiffness and the fabrication methods on the stress fields and lubrication performance are analyzed. The conclusions may potentially provide some insightful information for the design and analysis of functional materials and their engineering structures.

References

1.
Chen
,
W.
,
1971
, “
Computation of Stresses and Displacements in a Layered Elastic Medium
,”
Int. J. Eng. Sci.
,
9
(
9
), pp.
775
800
.
2.
Cai
,
S.
, and
Bhushan
,
B.
,
2005
, “
A Numerical Three-Dimensional Contact Model for Rough, Multilayered Elastic/Plastic Solid Surfaces
,”
Wear
,
259
(
7–12
), pp.
1408
1423
.
3.
Ye
,
N.
, and
Komvopoulos
,
K.
,
2003
, “
Effect of Residual Stress in Surface Layer on Contact Deformation of Elastic-Plastic Layered Media
,”
ASME J. Tribol.
,
125
(
4
), pp.
692
699
.
4.
Kot
,
M.
,
Rakowski
,
W.
,
Lackner
,
J. M.
, and
Major
,
Ł.
,
2013
, “
Analysis of Spherical Indentations of Coating-Substrate Systems: Experiments and Finite Element Modeling
,”
Mater. Des.
,
43
, pp.
99
111
.
5.
Zhou
,
K.
,
Keer
,
L. M.
, and
Wang
,
Q. J.
,
2011
, “
Semi-Analytic Solution for Multiple Interacting Three-Dimensional Inhomogeneous Inclusions of Arbitrary Shape in an Infinite Space
,”
Int. J. Numer. Meth. Eng.
,
87
(
7
), pp.
617
638
.
6.
Zhou
,
K.
,
Chen
,
W. W.
,
Keer
,
L. M.
,
Ai
,
X.
,
Sawamiphakdi
,
K.
,
Glaws
,
P.
, and
Wang
,
Q. J.
,
2011
, “
Multiple 3D Inhomogeneous Inclusions in a Half Space Under Contact Loading
,”
Mech. Mater.
,
43
(
8
), pp.
444
457
.
7.
Zhou
,
K.
,
Chen
,
W. W.
,
Keer
,
L. M.
, and
Wang
,
Q. J.
,
2009
, “
A Fast Method for Solving Three-Dimensional Arbitrarily Shaped Inclusions in a Half Space
,”
Comput. Methods Appl. Mech. Eng.
,
198
(
9–12
), pp.
885
892
.
8.
Zhou
,
K.
,
Keer
,
L. M.
, and
Wang
,
Q. J.
,
2011
, “
Analysis of Hard Coatings on a Substrate Containing Inhomogeneities
,”
J. Mech. Mater. Struct.
,
6
(
1–4
), pp.
627
639
.
9.
Dong
,
Q.
,
Zhou
,
K.
,
Wei
,
R.
,
Luo
,
J.
, and
Srikanth
,
N.
,
2015
, “
Analysis of Fluid Pressure, Interface Stresses and Stress Intensity Factors for Layered Materials With Cracks and Inhomogeneities Under Elastohydrodynamic Lubrication Contact
,”
Int. J. Mech. Sci.
,
93
, pp.
48
58
.
10.
Luo
,
J.
,
Liu
,
Y.
, and
Berger
,
E.
,
2000
, “
Interfacial Stress Analysis for Multi-Coating Systems Using an Advanced Boundary Element Method
,”
Comput. Mech.
,
24
(
6
), pp.
448
455
.
11.
Yu
,
C.
,
Wang
,
Z.
, and
Wang
,
Q. J.
,
2014
, “
Analytical Frequency Response Functions for Contact of Multilayered Materials
,”
Mech. Mater.
,
76
, pp.
102
120
.
12.
Wang
,
Z.
,
Yu
,
C.
, and
Wang
,
Q.
,
2015
, “
An Efficient Method for Solving Three-Dimensional Fretting Contact Problems Involving Multilayered or Functionally Graded Materials
,”
Int. J. Solids Struct.
,
66
, pp.
46
61
.
13.
Wei
,
J.
,
Zhang
,
A.
, and
Gao
,
P.
,
2016
, “
A Study of Spur Gear Pitting Under EHL Conditions: Theoretical Analysis and Experiments
,”
Tribol. Int.
,
94
, pp.
146
154
.
14.
Rehman
,
W. U.
,
Jiang
,
G.
,
Luo
,
Y.
,
Wang
,
Y.
,
Khan
,
W.
,
Rehman
,
S. U.
, and
Iqbal
,
N.
,
2018
, “
Control of Active Lubrication for Hydrostatic Journal Bearing by Monitoring Bearing Clearance
,”
Adv. Mech. Eng.
,
10
(
4
), pp. 1–17.
15.
Zhu
,
D.
, and
Wang
,
Q. J.
,
2011
, “
Elastohydrodynamic Lubrication: A Gateway to Interfacial Mechanics—Review and Prospect
,”
ASME J. Tribol.
,
133
(
4
), p.
041001
.
16.
Zhu
,
D.
,
Liu
,
Y.
, and
Wang
,
Q.
,
2014
, “
On the Numerical Accuracy of Rough Surface EHL Solution
,”
Tribol. Trans.
,
57
(
4
), pp.
570
580
.
17.
Pu
,
W.
,
Wang
,
J.
, and
Zhu
,
D.
,
2016
, “
Progressive Mesh Densification Method for Numerical Solution of Mixed Elastohydrodynamic Lubrication
,”
ASME J. Tribol.
,
138
(
2
), p.
021502
.
18.
Venner
,
C. H.
, and
Lubrecht
,
A. A.
,
2000
,
Multi-Level Methods in Lubrication
,
Elsevier, Amsterdam
,
The Netherlands
.
19.
Zhu
,
D.
,
2007
, “
On Some Aspects of Numerical Solutions of Thin-Film and Mixed Elastohydrodynamic Lubrication
,”
Proc. Inst. Mech. Eng., Part J
,
221
(
5
), pp.
561
579
.
20.
Liu
,
Y.
,
Chen
,
W. W.
,
Zhu
,
D.
,
Liu
,
S.
, and
Wang
,
Q. J.
,
2007
, “
An Elastohydrodynamic Lubrication Model for Coated Surfaces in Point Contacts
,”
ASME J. Tribol.
,
129
(
3
), pp.
509
516
.
21.
Liu
,
Y.
,
Wang
,
Q. J.
, and
Zhu
,
D.
,
2008
, “
Effect of Stiff Coatings on EHL Film Thickness in Point Contacts
,”
ASME J. Tribol.
,
130
(
3
), p.
031501
.
22.
Wang
,
Z.
,
Wang
,
W.
,
Wang
,
H.
, and
Hu
,
Y. Z.
,
2009
, “
Stress Analysis on Layered Materials in Point Elastohydrodynamic-Lubricated Contacts
,”
Tribol. Lett.
,
35
(
3
), pp.
229
244
.
23.
Wang
,
Z.
,
Yu
,
C.
, and
Wang
,
Q.
,
2015
, “
Model for Elastohydrodynamic Lubrication of Multilayered Materials
,”
ASME J. Tribol.
,
137
(
1
), p.
011501
.
24.
Reynolds
,
O.
,
1886
, “
On the Theory of Lubrication and Its Application to Mr. Beauchamp Tower's Experiments, Including an Experimental Determination of the Viscosity of Olive Oil
,”
Proc. R. Soc. London
,
40
(
242–245
), pp.
191
203
.
25.
Hu
,
Y. Z.
,
Wang
,
H.
,
Wang
,
W. Z.
, and
Zhu
,
D.
,
2001
, “
A Computer Model of Mixed Lubrication in Point Contacts
,”
Tribol. Int.
,
34
(
1
), pp.
65
73
.
26.
Peiran
,
Y.
, and
Shizhu
,
W.
,
1990
, “
A Generalized Reynolds Equation for Non-Newtonian Thermal Elastohydrodynamic Lubrication
,”
ASME J. Tribol.
,
112
(
4
), pp.
631
636
.
27.
Wang
,
W. Z.
,
Hu
,
Y. Z.
,
Liu
,
Y.
, and
Zhu
,
D.
,
2010
, “
Solution Agreement Between Dry Contacts and Lubrication System at Ultra-Low Speed
,”
Proc. Inst. Mech. Eng., Part J
,
224
(
10
), pp.
1049
1060
.
28.
van Leeuwen
,
H.
,
2009
, “
The Determination of the Pressure—Viscosity Coefficient of a Lubricant Through an Accurate Film Thickness Formula and Accurate Film Thickness Measurements
,”
Proc. Inst. Mech. Eng., Part J
,
223
(
8
), pp.
1143
1163
.
29.
Liu
,
Y.
,
Wang
,
Q. J.
,
Wang
,
W.
,
Hu
,
Y.
, and
Zhu
,
D.
,
2006
, “
Effects of Differential Scheme and Mesh Density on EHL Film Thickness in Point Contacts
,”
ASME J. Tribol.
,
128
(
3
), pp.
641
653
.
30.
Wang
,
F. S.
,
Block
,
J. M.
,
Chen
,
W. W.
,
Martini
,
A.
,
Zhou
,
K.
,
Keer
,
L. M.
, and
Wang
,
Q. J.
,
2009
, “
A Multilevel Model for Elastic-Plastic Contact Between a Sphere and a Flat Rough Surface
,”
ASME J. Tribol.
,
131
(
2
), p.
021409
.
31.
Glovnea
,
R.
, and
Spikes
,
H.
,
2001
, “
Elastohydrodynamic Film Collapse During Rapid Deceleration—Part I: Experimental Results
,”
ASME J. Tribol.
,
123
(
2
), pp.
254
261
.
32.
Zhao
,
J.
, and
Sadeghi
,
F.
,
2003
, “
Analysis of EHL Circular Contact Shut Down
,”
ASME J. Tribol.
,
125
(
1
), pp.
76
90
.
33.
Glovnea
,
R.
, and
Spikes
,
H.
,
2001
, “
Elastohydrodynamic Film Collapse During Rapid Deceleration—Part II: Theoretical Analysis and Comparison of Theory and Experiment
,”
ASME J. Tribol.
,
123
(
2
), pp.
262
267
.
34.
Lu
,
X.
,
Dong
,
Q.
,
Zhou
,
K.
,
Zhao
,
B.
, and
Zhao
,
B.
,
2018
, “
Numerical Analysis of Transient Elastohydrodynamic Lubrication During Startup and Shutdown Processes
,”
ASME J. Tribol.
,
140
(
4
), p.
041504
.
35.
O'Sullivan
,
T.
, and
King
,
R.
,
1988
, “
Sliding Contact Stress Field Due to a Spherical Indenter on a Layered Elastic Half-Space
,”
ASME J. Tribol.
,
110
(
2
), pp.
235
240
.
You do not currently have access to this content.