, Volume 4, Issue 4, pp 347–358 | Cite as

Identifying the optimal interfacial parameter correlated with hydrodynamic lubrication

  • Liang Guo
  • Patrick Wong
  • Feng Guo
Open Access
Research Article


The effects of boundary (liquid/solid) slip on hydrodynamics are well recognized. However, it is extremely difficult to quantify in-situ boundary slip in a lubrication contact. Therefore, an effective interfacial parameter that is well correlated with the lubrication effect is of practical significance. This paper presents an examination of common interfacial parameters, including surface tension, contact angle, contact angle hysteresis, and a recently proposed spreading parameter. Specimen surfaces of different hydro/oleophobicity were prepared and characterized using the aforementioned interfacial parameters. These samples were further used as bearing surfaces in hydrodynamic lubrication tests. The correlations of these parameters with the measured lubricating film thickness were examined and compared. The key parameter closely related to the hydrodynamic effect was identified.


bearing slip oleophobicity thin hydrodynamic film 



The work described in this paper was fully supported by the Research Grants Council of Hong Kong (Project No. CityU123411) and Natural Science Foundation of China (Project No. 51275252). The authors would also like to express sincere thanks to Dr. X. Zhou of SKF for providing the EGC coating in this work.


  1. [1]
    Spikes H A. The half-wetted bearing: Part 1–Extended Reynolds equation. J Eng Tribol 217: 1–14 (2003)Google Scholar
  2. [2]
    Choo J H, Glovnea R P, Forrest A K, Spikes H A. A low friction bearing based on liquid slip at the wall. J Tribol 129: 611–620 (2007)CrossRefGoogle Scholar
  3. [3]
    Guo F, Wong P L. Full and partial boundary slippage effect on squeeze film bearings. Tribol Int 43: 997–1004 (2010)CrossRefGoogle Scholar
  4. [4]
    Tauviqirrahman M, Ismail R, Jamari J, Schipper D J. Combined effect of texturing and boundary slippage in lubricated sliding contacts. Tribo Int 66: 274–281 (2013)CrossRefzbMATHGoogle Scholar
  5. [5]
    Craig V S J, Neo C, Williams D R M. Shear-dependent boundary slip in an aqueous Newtonian liquid. Phys Rev Lett 87(5): 054504 (2001)CrossRefGoogle Scholar
  6. [6]
    Zhu Y X, Granick S. Rate-dependent slip of Newtonian liquid at smooth surfaces. Phys Rev Lett 87(9): 096105 (2001)CrossRefGoogle Scholar
  7. [7]
    Spikes H A, Granick S. Equation for slip of simple liquids at smooth solid surfaces. Langmuir 19: 5065–5071 (2003)CrossRefGoogle Scholar
  8. [8]
    Hild W, Opitz A, Schaefer J, Scherge M. The effect of wetting on the microhydrodynamics of surfaces lubricated with water and oil. Wear 254: 871–875 (2003)CrossRefGoogle Scholar
  9. [9]
    Baudry J, Charlaix E, Tonck A, Mazuyer D. Experimental evidence for a large slip effect at a nonwetting fluid-solid interface. Langmuir 17: 5232–5236 (2001)CrossRefGoogle Scholar
  10. [10]
    Tretheway D C, Meinhart C D. Apparent fluid slip at hydrophobic microchannel walls. Phys Fluids 14: L9–L12 (2002)CrossRefGoogle Scholar
  11. [11]
    Guo F, Yang S, Ma C, Wong P. Experimental study on lubrication film thickness under different interface wettabilities. Tribol Lett 54: 81–88 (2014)CrossRefGoogle Scholar
  12. [12]
    Bongaerts J, Fourtouni K, Stokes J. Soft-tribology: lubrication in a compliant PDMS–PDMS contact. Tribol Int 40: 1531–1542 (2007)CrossRefGoogle Scholar
  13. [13]
    Joseph P, Tabeling P. Direct measurement of the apparent slip length. Phys Rev E 71: 035303 (2005)CrossRefGoogle Scholar
  14. [14]
    Kikuchi K, Mochizuki O. Micro PIV measurement of slip flow on a hydrogel surface. Meas Sci Technol 25: 065702 (2014)CrossRefGoogle Scholar
  15. [15]
    Ponjavic A, Chennaoui M, Wong J S S. Through-thickness velocity profile measurements in an elastohydrodynamic contact. Tribo Lett 50(2): 261–277 (2013)CrossRefGoogle Scholar
  16. [16]
    Kalin M, Polajnar M. The correlation between the surface energy, the contact angle and the spreading parameter, and their relevance for the wetting behavior of DLC with lubricating oils. Tribol Int 66: 225–233 (2013).CrossRefGoogle Scholar
  17. [17]
    Kalin M, Polajnar M. The wetting of steel, DLC coatings, ceramics and polymers with oils and water: The importance and correlations of surface energy, surface tension, contact angle and spreading. App Surf Sci 293: 97–108 (2014)CrossRefGoogle Scholar
  18. [18]
    Fowkes F M. Attractive forces at interfaces. J Ind & Eng Chem 56: 40–52 (1964)CrossRefGoogle Scholar
  19. [19]
    Wang D, Wang X, Liu X, Zhou F. Engineering a titanium surface with controllable oleophobicity and switchable oil adhesion. J Phys Chem C 114: 9938–9944 (2010).CrossRefGoogle Scholar
  20. [20]
    Bhushan B, Her E K. Fabrication of superhydrophobic surfaces with high and low adhesion inspired from rose petal. Langmuir. 26: 8207–8217 (2010)CrossRefGoogle Scholar
  21. [21]
    Owens D K, Wendt R. Estimation of the surface free energy of polymers. J App Poly Sci 13: 1741–1747 (1969)CrossRefGoogle Scholar
  22. [22]
    Yaminsky V. Molecular mechanisms of hydrophobic transitions. J Adhes Sci Technol 14: 187–233 (2000)CrossRefGoogle Scholar
  23. [23]
    Extrand C. Contact angles and their hysteresis as a measure of liquid-solid adhesion. Langmuir 20: 4017–4021 (2004)CrossRefGoogle Scholar
  24. [24]
    Whyman G, Bormashenko E, Stein T. The rigorous derivation of Young, Cassie–Baxter and Wenzel equations and the analysis of the contact angle hysteresis phenomenon. Chem Phys Lett 450: 355–359 (2008)CrossRefGoogle Scholar
  25. [25]
    Guo F, Wong P L, Fu Z, Ma C. Interferometry measurement of lubricating films in slider-on-disc contacts. Tribol Lett 39: 71–79 (2010)CrossRefGoogle Scholar
  26. [26]
    Guo L, Wong P L, Guo F, Liu H C. Determination of thin hydrodynamic lubricating film thickness using dichromatic interferometry. Appl Optics 53: 6066–6072 (2014)CrossRefGoogle Scholar
  27. [27]
    Guo F, Wong P L. A multi-beam intensity-based approach for lubricant film measurements in non-conformal contacts. J Eng Tribol 216(5): 281–291 (2002)Google Scholar
  28. [28]
    Ma G J, Wu C W, Zhou P. Multi-linearity algorithm for wall slip in two-dimensional gap flow. Int J Numer Meth Eng 69: 2469–2484 (2007)CrossRefzbMATHGoogle Scholar
  29. [29]
    Guo L, Wong PL, Guo F. Boundary yield stress and interfacial potential energy barrier in thin film hydrodynamic lubrication. Tribol Lett 62: 7 (2016)CrossRefGoogle Scholar
  30. [30]
    MacDougall G, Ockrent C. Surface energy relations in liquid/solid systems. I. The adhesion of liquids to solids and a new method of determining the surface tension of liquids. Proc Royal Soc Lond A Math Phys & Engg Sci 981: 151–173 (1942)CrossRefGoogle Scholar
  31. [31]
    Barrat J L, Bocquet L. Large slip effect at a nonwetting fluid-solid interface. Phys Rev Lett 82: 4671 (1999)CrossRefGoogle Scholar
  32. [32]
    Huang D M, Sendner C, Horinek D, Netz R R, Bocquet L. Water slippage versus contact angle: A quasiuniversal relationship. Phys Rev Lett 101: 22610 (2008)Google Scholar

Copyright information

© The author(s) 2016

Open Access: The articles published in this journal are distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  1. 1.Department of Mechanical and Biomedical EngineeringCity University of Hong KongHong KongChina
  2. 2.Mechanical Engineering DepartmentQingdao Technological UniversityQingdaoChina

Personalised recommendations