Skip to main content
SpringerLink
Log in

Lubricant Rupture Ratio at Elastohydrodynamically Lubricated Contact Outlet

  • Original Paper
  • Published:
Tribology Letters Aims and scope Submit manuscript

Abstract

Elastohydrodynamically lubricated (EHL) contacts rarely exist as single contacts. Multiple contacts or single contacts subjected to the repeated over-rolling represent more often the case in practical applications. A typical example is the rolling element bearing. A lubricant rupture mechanism at each contact outlet determines the lubricant availability to the succeeding contact. This work presents a quantitative description of the lubricant film thickness rupture in EHL contact outlet with the use of the fluorescent microscopy. A rupture ratio of the film thickness between two diverging surfaces exiting the contact was measured for both pure rolling and rolling–sliding conditions. The influence of variation of several parameters such as lubricant properties, rolling speed or rolling element ellipticity to the lubricant rupture ratio was investigated. Understanding of the physical phenomena of the lubricant rupture extends further possibilities in both experimental and theoretical researches of the starved EHL.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

Similar content being viewed by others

Abbreviations

Ca :

Capillary number; \(\frac{\eta _{0}U}{\sigma }\)

\(h_\mathrm{c}\) :

Central film thickness

\(u_{1,2}\) :

Entrainment speeds of surfaces

subscripts 1;2:

Relation to the disc;ball

\(u_\mathrm{m}\) :

Mean speed; \((u_1+u_2)/2\)

SRR:

Slide-to-roll ratio; \(\frac{2(u_1-u_2)}{(u_1+u_2)}\)

k :

Ellipticity of the element

\(\sigma\) :

Surface tension

\(\eta\) :

Viscosity at atmospheric pressure

\(\delta _1\) :

Dimensionless film thickness on the disc

\(\delta _2\) :

Dimensionless film thickness on the ball

\(\varDelta\) :

Rupture ratio parameter; \(\frac{\delta _1}{\delta _1+\delta _2}\)

References

  1. Svoboda, P., Kostal, D., Krupka, I., Hartl, M.: Experimental study of starved EHL contacts based on thickness of oil layer in the contact inlet. Tribol. Int. 67, 140–145 (2013)

    Article  Google Scholar 

  2. Lugt, P.M., Morales-Espejel, G.E.: A review of elasto-hydrodynamic lubrication theory. Tribol. Trans. 54(3), 470–496 (2011)

    Article  Google Scholar 

  3. van Zoelen, M.T., Venner, C.H., Lugt, P.M.: The prediction of contact pressure-induced film thickness decay in starved lubricated rolling bearings. Tribol. Trans. 53(6), 831–841 (2010)

    Article  Google Scholar 

  4. Weinstein, S.J., Ruschak, K.J.: Coating rows. Ann. Rev. Fluid Mech. 36, 29–53 (2004)

    Article  Google Scholar 

  5. Savage, M.D.: Cavitation in lubrication—1. On boundary conditions and cavity-fluid interfaces. J. Fluid Mech. 80(pt 4), 743–755 (1977)

    Article  Google Scholar 

  6. Ruschak, K.J.: Boundary conditions at a liquid/air interface in lubrication flow. J. Fluid Mech. 119, 107–120 (1982)

    Article  Google Scholar 

  7. Taroni, M., Breward, C.J.W., Howell, P.D., Oliver, J.M.: Boundary conditions for free surface inlet and outlet problems. J. Fluid Mech. 708, 100–110 (2012)

    Article  Google Scholar 

  8. Coyne, J.C., Elrod JR, H.: Conditions for the rupture of a lubricating film - 1. ASME- Paper 69-Lub-3 (1969)

  9. Coyne, J.C., Elrod Jr, H.: Conditions for the rupture of a lubricating film—2. J. Lubric. Technol. Trans. ASME 93 Ser F(1), 156–167 (1971)

    Article  Google Scholar 

  10. Reynolds, O.: 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. Lond. 40, 191–203 (1886)

    Article  Google Scholar 

  11. Hewson, R.W.: Free surface model derived from the analytical solution of stokes flow in a wedge. J. Fluids Eng. Trans. ASME 131(4), 0412051–0412055 (2009)

    Article  Google Scholar 

  12. Hewson, R.W., Kapur, N., Gaskell, P.H.: A model for film-forming with Newtonian and shear-thinning fluids. J. Nonnewton. Fluid Mech. 162(1–3), 21–28 (2009)

    Article  Google Scholar 

  13. Lee-Prudhoe, I., Venner, C.H., Cann, P.M., Spikes, H.: Experimental and theoretical approaches to thin film lubrication problems. Solid Mech. Appl. 134, 241–255 (2006)

    Google Scholar 

  14. Chevalier, F., Lubrecht, A.A., Cann, P.M.E., Colin, F., Dalmaz, G.: Starvation phenomena in E.H.L. point contacts. Tribol. Ser. 31, 213–223 (1996)

    Article  Google Scholar 

  15. van Zoelen, M.T., Venner, C.H., Lugt, P.M.: Free surface thin layer flow on bearing raceways. J. Tribol. 130(2), 1–10 (2008)

    Google Scholar 

  16. Bruyere, V., Fillot, N., Morales-Espejel, G.E., Vergne, P.: A two-phase flow approach for the outlet of lubricated line contacts. J. Tribol. 134(4), (2012). doi: 10.1115/1.4006277

    Article  Google Scholar 

  17. Smart, A.E., Ford, R.A.J.: Measurement of thin liquid films by a fluorescence technique. Wear 29(1), (1974)

  18. Sugimura, J., Hashimoto, M., Yamamoto, Y.: Study of elastohydrodynamic contacts with fluorescence microscope. Tribol. Ser. 38, 609–617 (2000)

    Article  Google Scholar 

  19. Lyon, H.O., Prento, P.: Haugland rp. handbook of fluorescent probes and research chemicals, 6th ed. Ugeskrift for laeger 159(27), 4285–4286 (1997)

    Google Scholar 

  20. Azushima, A.: In lubro 3d measurement of oil film thickness at the interface between tool and workpiece in sheet drawing using a fluorescence microscope. Tribol. Int. 38(2), 105–112 (2005)

    Article  Google Scholar 

Download references

Acknowledgments

This work is an output of cooperation between Czech Science Foundation under Project No.: 13-30879P and NETME Centre, regional R&D centre built with the financial support from the Operational Programme Research and Development for Innovations within the project NETME Centre (New Technologies for Mechanical Engineering), Reg. No. CZ.1.05/2.1.00/01.0002 and, in the follow-up sustainability stage, supported through NETME CENTRE PLUS (LO1202) by financial means from the Ministry of Education, Youth and Sports under the ‘National Sustainability Programme I’.

Author information

Authors and Affiliations

  1. Faculty of Mechanical Engineering, Institute of Machine and Industrial Design, Brno University of Technology, Technicka 2896/2, 61669, Brno, Czech Republic

    David Košťál, David Nečas, Petr Šperka, Petr Svoboda, Ivan Křupka & Martin Hartl

Authors
  1. David Košťál
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. David Nečas
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Petr Šperka
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Petr Svoboda
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Ivan Křupka
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Martin Hartl
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to David Košťál.

Additional information

This article is part of the Topical Collection on STLE Tribology Frontiers Conference 2014.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Košťál, D., Nečas, D., Šperka, P. et al. Lubricant Rupture Ratio at Elastohydrodynamically Lubricated Contact Outlet. Tribol Lett 59, 39 (2015). https://doi.org/10.1007/s11249-015-0565-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s11249-015-0565-7

Keywords

Search

Navigation