A full numerical analysis is carried out to simulate the thermal elastohydrodynamic lubrication (TEHL) of an eccentric-tappet pair. Comparisons between thermal and isothermal results are given to reveal the role of the thermal effect. Under various eccentricities, the influences of two surfaces moving in opposite directions on pressure and film thickness profiles are analyzed and explained by the mechanism of the temperature-viscosity wedge. Pressure and film thickness profiles, the temperature and velocity distributions at zero entraining velocity are discussed fully. Particular analyses are given on the entrapped immobile surface layers that influence the velocity distribution at zero entraining velocity. Furthermore, in a working cycle, variations of central and minimum film thicknesses and frictional coefficients, under different eccentricities, are discussed.
Issue Section:
Technical Papers
1.
Dowson, D., Harrison, P., and Taylor, C. M., 1984, “The Lubrication of Automotive Cams and Followers,” Proc. 12th Leeds-Lyon Symposium on Tribology, pp. 599–609.
2.
Bedewi, M. A., Dowson, D., and Taylor, C. M., 1984, “Elastohydrodynamic Lubrication of Line Contacts Subjected to Time Dependent Loading with Particular Reference to Roller Bearings and Cams and Followers,” Proc. 12th Leeds-Lyon Symposium on Tribology, pp. 289–304.
3.
Holland, J., 1978, “Zur Ausbilding Eines Tragf a¨ Higen Schmierfil ms Zwischen Nocken und Sto¨ssel,” MTZ, 39, ss. 225–231.
4.
Holland, J., 1978, “Die Instation a¨re Elastohydrodynamik Konstruktiion,” 30, H.9, ss. 363–369.
5.
Yu, H., Zhan, X., and Huang, Y., 1984, “The Computation of Unsteadily Loaded EHL Film Thickness and Other Lubrication Parameters of Cam-Tappet Pairs of I. C. Engines and Analysis of Their Performance,” Proc. 12th Leeds-Lyon Symposium on Tribology, pp. 171–180.
6.
Ai
, X.
, and Yu
, H.
, 1989
, “A Numerical Analysis for the Transient EHL Process of a Cam-Tappet Pair in I.C. Engine
,” ASME J. Tribol.
, 111
, pp. 413
–417
.7.
Messe´
, S.
, and Lubrecht
, A. A.
, 2000
, “Transient elastohydrodynamic analysis of an overhead cam/tappet contact
,” Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol.
, 214
, pp. 415
–425
.8.
Dyson
, A.
, and Wilson
, A. R.
, 1968
, “Film thicknesses in Elastohydrodynamic Lubrication at High Sidle/Roll Ratios
,” Proc. Inst. Mech. Eng.
, 193
, 3P
, pp. 81
–97
.9.
Yang
, P.
, Qu
, S.
, Chang
, Q.
, and Guo
, F.
, 2001
, “On the Theory of Thermal Elastohydrodynamic Lubrication at High Slide-Roll Ratios: Line Contact Solution
,” ASME J. Tribol.
, 123
, pp. 36
–41
.10.
Kaneta
, M.
, Nishikawa
, H.
, Kanada
, T.
, and Matsuda
, K.
, 1996
, “Abnormal Phenomena Appearing in EHL Contacts
,” ASME J. Tribol.
, 118
, pp. 886
–892
.11.
Kaneta
, M.
, Nishikawa
, H.
, Kameishi
, K.
, and Sakai
, T.
, 1992
, “Effects of Elastic Moduli of Contact Surfaces in Elastohydrodynamic Lubrication
,” ASME J. Tribol.
, 114
, pp. 75
–80
.12.
Yang
, P.
, and Wen
, S.
, 1990
, “A Generalized Reynolds Equation for Non-Newtonian Thermal Elastohydrodynamic Lubrication
,” ASME J. Tribol.
, 112
, pp. 631
–636
.13.
Yang
, P.
, and Shen
, J.
, 1996
, “On the Theory of Time-Dependent Micro-TEHL for a Non-Newtonian Lubrication in Line Contacts
,” Lubr. Sci.
, 8
, pp. 297
–312
.14.
Zhu
, D.
, and Wen
, S.
, 1984
, “A Full Numerical Solution for the Thermoelastohydrodynamic Problem in Elliptical Contact
,” ASME J. Tribol.
, 106
, pp. 246
–254
.15.
Ma
, M. T.
, 1997
, “An Expedient Approach to the Non-Newtonian Thermal EHL in Heavily Loaded Point Contacts
,” Wear
, 206
, pp. 100
–112
.16.
Roelands, C. J. A., 1966, “Correlation Aspects of Viscosity-Temperature-Pressure Relationship of Lubricating Oils,” Ph.D. thesis, Delft University of Technology, the Netherlands.
17.
Venner, C. H., 1991, “Multilevel Solution of the EHL Line and Point Contact Problems,” Ph.D. thesis, University of Twente, the Netherlands.
18.
Wang
, J.
, Qu
, S.
, and Yang
, P.
, 2001
, “Simplified Multigrid Technique for the Numerical Solution to the Steady-State and Transient EHL Line Contacts and the Arbitrary Entrainment EHL Point Contacts
,” Tribol. Int.
, 34
, pp. 191
–202
.19.
Yang
, P.
, and Rodkiewicz
, C. M.
, 1992
, “On the Numerical Analysis to the Thermal Elastohydrodynamic Lubrication of a Tilting Pad Inclusive of Side Leakage
,” STLE Tribol. Trans.
, 40
, pp. 259
–266
.20.
Qu
, S.
, Yang
, P.
, and Guo
, F.
, 2000
, “Theoretical Investigation on the Dimple Occurrence in the Thermal EHL of Simple Sliding Steel-Glass Circular Contacts
,” Tribol. Int.
, 33
, pp. 487
–505
.21.
Guo
, F.
, Yang
, P.
, and Qu
, S.
, 2001
, “On the Theory of Thermal Elastohydrodynamic Lubrication at High Slide-Roll Ratios—Circular Glass-Steel Contact Solution at Opposite Sliding
,” ASME J. Tribol.
, 123
, pp. 816
–821
.22.
Yang
, P.
, Qu
, S.
, Kaneta
, M.
, and Nishikawa
, H.
, 2001
, “Formation of Steady Dimples in Point TEHL Contacts
,” ASME J. Tribol.
, 123
, pp. 42
–49
.23.
Liu X., Yang P., and Kaneta M., 2003, “Analysis of non-Newtonian Thermal Elastohydrodynamic Lubrication Based on the Surface Dimple Phenomena” (in Chinese), Tribology (in China), 23: in press.
24.
Yagi, K., Kyogoku, K., and Nakahara, T., 2000, “Temperature Measurements of Oil Film and Surface in Point Contact EHL under High Slip Ratio Condition,” Proc. JAST Tribology Conference, Tokyo 2000-5, pp. 287–288 (in Japanese).
25.
Shogrin, B. A., Jones, W. R., Kingsbury, E. P., Jansen, M. J., and Prahl, J. M., 1998, “Experimental Study of Load Carrying Capacity of Point Contacts at Zero Entrainment Velocity,” NASA TM 208650.
Copyright © 2003
by ASME
You do not currently have access to this content.
