EHL Film Thickness Behaviour Under High Pressure — Comparison between Numerical and Experimental Results

  • Martin Hartl
  • Ivan Křupka
  • Dong Zhu
Part of the Solid Mechanics and Its Applications book series (SMIA, volume 134)


This paper is devoted to the study of the behaviour of thin lubricant films under high contact pressures. Central film thickness values obtained from optical measurements are compared with numerical solutions from Zhu and Hu’s model. The comparison indicates that both the numerical solutions and the experimental measurements are in good agreement with the Hamrock-Dowson formula at moderate loads and speeds. However, at low speeds and heavy loads accelerated non-linear film thickness reductions shown on the log-log scale are observed in the simulation results and confirmed by the experimental data.


thin lubricant films central film thickness high contact pressure 


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  1. [1]
    D. Zhu, Elastohydrodynamic Lubrication in Extended Parameter Ranges — Part 1: Speed Effect, Tribology Transactions 45, 540–548 (2002).Google Scholar
  2. [2]
    R. Gohar, Oil Film Thickness and Rolling Friction in Elastohydrodynamic Point Contact, Trans. of the ASME, Journal of Lubrication Technology 93, 371–382 (1971).Google Scholar
  3. [3]
    C.R. Gentle, R.R. Duckworth and A. Cameron, Elastohydrodynamic Film Thickness at Extreme Pressures, Trans. of the ASME, Journal of Lubrication Technology 97, 383–389 (1975).Google Scholar
  4. [4]
    G. Dalmaz, Simulating Angular Ball Bearing Lubricated Elliptical Contacts — Film Thickness and Traction Measurement, Tribology International 11, 273–279 (1978).CrossRefGoogle Scholar
  5. [5]
    G.J., Johnston, R. Wayte and H.A. Spikes, The Measurement and Study of Very Thin Lubricant Films in Concentrated Contacts, Tribology Transactions 34, 187–194 (1991).Google Scholar
  6. [6]
    L. Gustafsson, E. Höglund and O. Marklund, Measuring Lubricant Film Thickness with Image Analysis, Proceedings Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 208, 199–205 (1994).Google Scholar
  7. [7]
    P.M. Cann, H.A. Spikes and J. Hutchinson, The Development of a Spacer Layer Imaging Method (SLIM) for Mapping Elastohydrodynamic Contacts, Tribology Transactions 39, 915–921 (1996).Google Scholar
  8. [8]
    J.B. Luo, S.Z. Wen and P. Huang, Thin film Lubrication 1. Study on the Transition between EHL and Thin Film Lubrication Using a Relative Optical Interference Intensity Technique, Wear 194, 107–115 (1996).CrossRefGoogle Scholar
  9. [9]
    M. Hartl, I. Křupka, R. Polišcuk, M. Liška, J. Molimard, P. Vergne and M. Querry, Thin Film Colorimetric Interferometry, Tribology Transactions 44, 270–276 (2001).Google Scholar
  10. [10]
    F. Guo and P.L. Wong, A Multiple-Beam Intensity-Based Approach for Thin Lubricant Film Measurement in Non-Conformal Contacts, Proceedings Institution of Mechanical Engineers, Journal of Engineering Tribology 216, 281–291 (2002).CrossRefGoogle Scholar
  11. [11]
    M. Smeeth, P.M. Cann and H.A. Spikes, Measurement of Elastohydrodynamic Film Formation in Rolling Contacts at Very High Pressure, in Lubricants and Lubrication, Proceedings of the 21st Leeds-Lyon Symposium on Tribology, pp. 497–502 (1995).Google Scholar
  12. [12]
    M. Smeeth and H.A. Spikes, Central and Minimum Elastohydrodynamic Film Thickness at High Contact Pressure, Trans. of the ASME, Journal of Tribology 119, 291–296 (1997).Google Scholar
  13. [13]
    I. Křupka, M. Hartl, R. Polišcuk and M. Liška, Experimental Study of Central and Minimum Elastohydrodynamic Film Thickness by Colorimetric Interferometry Technique, Tribology Transactions 43, 611–618 (2000).Google Scholar
  14. [14]
    M. Hartl, I. Křupka and M. Liška, Direct Observation of the Behaviour of Real Surface Roughness Passing through EHD Point Contact, in Transient Processes in Tribology, Proceedings of the 30th Leeds-Lyon Symposium on Tribology, pp. 419–428 (2004).Google Scholar
  15. [15]
    B.O. Jacobson and P. Vinet, A Model for the Influence of Pressure on the Bulk Modulus and the Influence of Temperature on the Solidification Pressure of Liquid Lubricants, Trans. of the ASME, Journal of Tribology 109, 709–713 (1987).CrossRefGoogle Scholar
  16. [16]
    X. Ai, Numerical Analyses of Elastohydrodynamically Lubricated Line and Point Contacts with Rough Surfaces by Using Semi-System and Multigrid Methods, Ph.D. Dissertation, Northwestern University, Evanston, IL (1993).Google Scholar
  17. [17]
    Y.Z. Hu and D. Zhu, A Full Numerical Solution to the Mixed Lubrication in Point Contacts, Trans. of the ASME, Journal of Tribology 122, 1–9 (2000).CrossRefGoogle Scholar
  18. [18]
    D. Zhu and Y.Z. Hu, A Computer Program Package for the Prediction of EHL and Mixed Lubrication Characteristics, Friction, Subsurface Stresses and Flash Temperatures Based on Measured 3-D Surface Roughness, Tribology Transactions 44, 383–390 (2001).Google Scholar

Copyright information

© Springer 2006

Authors and Affiliations

  • Martin Hartl
    • 1
  • Ivan Křupka
    • 1
  • Dong Zhu
    • 2
  1. 1.Faculty of Mechanical EngineeringBrno University of TechnologyBrnoThe Czech Republic
  2. 2.Eaton CorporationSouthfieldUSA

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