The rheological behavior of oil-in-water emulsions has been studied as a function of oil concentration, shear strain rate, pressure and temperature. Results are discussed and correlated with several models which take into account the physical structure of emulsions. At low and medium shear rates and high concentrations, the emulsion’s behavior is non-Newtonian while under high shear rates, it becomes Newtonian. At ambient pressure, the viscosity of emulsions is weak and less temperature dependent than the base oil. The difference between the base oil and emulsion’s viscosity is less pronounced at high pressure. These tendencies are summarized by estimating the film formation ability of these lubricants. The oil concentration is the dominant parameter: if at low concentration the emulsions film formation ability is very weak, the results obtained at high concentration show a significant increase. This last point should be helpful to explain previous observations related to oil concentration variations inside the contact.

1.
Bair, S., 1992, An experimental verification of the significance of the reciprocal asymptotic isoviscous pressure for EHD lubricants, STLE preprint no. 92-AM-2H-1, presented at the 47th Annual Meeting in Philadelphia, USA, May 4-7, 1992.
2.
Barker
D. C.
,
Johnston
G. J.
, and
Spikes
H. A.
,
1993
, “
EHD film formation and starvation of oil-in-water emulsions
,”
Tribology Transactions
, Vol.
36
, no.
4
, pp.
565
572
.
3.
Benali
L.
,
1993
, “
Rheological and granulometrical studies of a cutting oil emulsion, I. The effects of oil concentration
,”
Journal of Colloid and Interface Science
, Vol.
156
, pp.
454
461
.
4.
Chong
J. S.
,
Christiansen
E. B.
, and
Baer
A. D.
,
1971
, “
Rheology of concentrated suspensions
,”
J. Appl. Polymer Sci
, Vol.
15
, pp.
2007
2021
.
5.
Eilers
H.
,
1943
, “
Die viskositats-konzentrationsabhangigkeit kolloider systeme in organischen losungsmitteln
,”
Kolloid Zeitschrift
, Vol.
102
, pp.
154
169
.
6.
Einstein
A.
,
1906
, “
Eine neue bestimmung der molekul-dimensionen
,”
Ann. Phys.
, Vol.
19
, pp.
289
306
.
7.
Harrison, G., 1976, The dynamic properties of supercooled liquids. Academic Press, London, 199 pp.
8.
Isaksson, O., 1986 “Water-based hydraulic fluids, rheology and elastohydrodynamic lubrication,” Doctoral thesis, 1986; J3D, Lulea University of Technology, 1986, 111 pp.
9.
Kimura, Y., and Okada, K., 1987 “Film thickness at elastohydrodynamic conjunctions lubricated with oil-in-water emulsions,” I. Mech. E., C176/87, pp. 85–90.
10.
Kimura
Y.
, and
Okada
K.
,
1989
, “
Lubricating properties of oil-in-water emulsions
,”
Tribology Transactions
, Vol.
32
, no.
4
, pp.
524
532
.
11.
Lissant, K. J., 1974, Emulsions and emulsion technology. Vol. 1, K. J, Lissant, ed,. Marcel Dekker, New York.
12.
Mooney
M.
,
1951
, “
The viscosity of a concentrated suspension of spherical particles
,”
Journal of Colloid Science
, Vol.
6
, pp.
162
170
.
13.
Pal
R.
,
Rhodes
E.
,
1985
, “
A novel viscosity correlation for non-Newtonian concentrated emulsion
,”
Journal of Colloid and Interface Science
, Vol.
107
, no.
2
, pp.
301
307
.
14.
Pal
R.
,
Bhattacharya
S. N.
, and
Rhodes
E.
,
1986
, “
Flow behaviour of oil-in-water emulsions
,”
The Canadian Journal of Chemical Engineering
, Vol.
64
, pp.
3
10
.
15.
Pal
R.
, and
Rhodes
E.
,
1989
, “
Viscosity/concentration relationships for emulsions
,”
Journal of Rheology
, Vol.
33
, no.
7
, pp.
1021
1045
.
16.
Pal
R.
,
1990
, “
Evaluation of the Mooney viscosity/concentration equation for liquid-liquid emulsions
,”
Chemical Engineering Communications
, Vol.
89
, pp.
209
214
.
17.
Quemada
D.
,
1977
, “
Rheology of concentrated dispersed systems and minimum energy dissipation principle
,”
Rheol. Acta
, Vol.
16
, pp.
82
94
.
18.
Reynaud, P., and Vergne, P., 1992 “High pressure behavior of space liquid lubricants,” Proceedings of the 8th International Colloquium Tribology, “Tribology 2000,” paper 19.12, 14-16 January 1992, Technische Akademie Esslingen.
19.
Roscoe
R.
,
1952
, “
The viscosity of suspensions of rigid spheres
,”
Br. Journal of Applied Physics
, Vol.
3
, pp.
267
269
.
20.
Sherman, P., 1983, Encyclopedia of Emulsion Technology, Vol. 1: Basic Theory, Chapter 7: Rheological Properties of Emulsions, edited by P, Becher, ed,. Marcel Dekker, New York, 725 p.
21.
Tanishita
I.
,
Nagashima
A.
, and
Murai
Y.
,
1971
, “
Correlation of viscosity, thermal conductivity and Prandtl number for water and steam as a function of temperature and pressure
,”
Bulletin of the JSME
, Vol.
14
, no.
77
, pp.
1187
1198
.
22.
Tozaki, Y., Asanabe, S., Matsumoto, S., Fukutomi, M., Akizuki, Y., Kajiwara, T., 1989 “Viscosity and EHL properties of O/W emulsions for cold-rolling operations,” EUROTRIB 89, Helsinki, pp. 388–393.
23.
Vergne, P., 1985 “Contribution a` l’e´tude du contact E.H.D,: de´formation des surfaces, caracte´risation haute pression des lubrifiants, The´se de Docteur-Inge´nieur soutenue le 21/05/85 a` l’INSA de Lyon, no. d’ordre IDI 18506, 241 p.
24.
Vergne
P.
, and
Roche
G.
,
1991
, “
Measurement of physical properties in liquids under high pressure by ultrasonic technique
,”
High Pressure Research
, Vol.
8
, pp.
516
518
.
25.
Viswanath, D. S., and Natarajan, G., 1989, Data Book on the Viscosity of Liquids, Hemisphere, 990 pp.
26.
Wan
G. T. Y.
,
Kenny
P.
, and
Spikes
H. A.
,
1984
, “
Elastohydrodynamic properties of water-based fire-resistant hydraulic fluids
,”
Tribology International
, Vol.
17
, no.
6
, pp.
309
315
.
27.
Wilson
W. R. D.
,
Sakaguchi
Y.
, and
Schmid
S. R.
,
1993
, “
A dynamic concentration model for lubrication with oil-in-water emulsions
,”
Wear
, Vol.
161
, pp.
207
-
212
.
28.
Wilson
W. R. D.
,
Sakaguchi
Y.
, and
Schmid
S. R.
,
1994
, “
A mixed flow model for lubrication with emulsions
,”
Tribology Transactions
, Vol.
37
, no.
3
, pp.
543
-
551
.
29.
Wilson, W. R. D., 1995 “Lubrication in metal forming,” Proceedings of the 21th Leeds-Lyon Symposium on Tribology, Lubricants and Lubrication, Leeds 6–9th September 1995, p. 101–112, D. Dowson et al. (Editors), Tribology Series 30, Elsevier Science B.V.
30.
Wilson, W. R. D., and Walowit, J. A., 1972 “An isothermal lubrication theory for strip rolling with front and back tension,” Tribology Convention 1971, Inst. of Mech. Eng., London, p. 164-172.
31.
Zhu
D.
,
Biresaw
G.
,
Clark
S. J.
, and
Kasun
T. J.
,
1994
, “
Elastohydrodynamic lubrication with O/W emulsions
,”
ASME JOURNAL OF TRIBOLOGY
, Vol.
116
, p.
310
320
.
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