Home Friction Article
PDF (5.3 MB)
Collect
Submit Manuscript
Research Article | Open Access

Roughness induced variation as a new mechanism for hydrodynamic lubrication between parallel surfaces

Pau Català1()Vallbé-Mumbrú Marc2Francesc Pérez-Ràfols3
Department of Mechanical Engineering, Manresa School of Engineering EPSEM, Universitat Politècnica de Catalunya, Av. de les Bases de Manresa, 61-73, Manresa, 08242, Catalunya, Spain
Department of Mining, Industrial and ICT Engineering, Manresa School of Engineering EPSEM, Universitat Politècnica de Catalunya, Av. de les Bases de Manresa, 61-73, Manresa, 08242, Catalunya, Spain
Serra Hunter Fellow, Department of Mining, Industrial and ICT Engineering, Manresa School of Engineering EPSEM, Universitat Politècnica de Catalunya, Av. de les Bases de Manresa, 61-73, Manresa, 08242, Catalunya, Spain
Show Author Information

Graphical Abstract

View original image Download original image

Abstract

This work proposes a new lift mechanism capable of explaining the hydrodynamic lift observed in real mechanical face seals with parallel surfaces. While it is well established that roughness is a key factor inducing such lift, its effect is commonly explained in the form of micro-wedges and asperity-level cavitation. The novelty of this work is to consider roughness induced random variability in the flow restriction, which induces effective wedges. First, a dedicated stochastic two-scale model is developed and used to demonstrate the proposed new mechanism in a case study. We demonstrate that the described new mechanism acts at scales comparable to the macroscopic size of the seal, much larger than the commonly considered micro-wedges. Afterwards, the limitations for this new proposed mechanism are discussed.

References

[1]

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. Phil Trans R Soc 177: 157–234 (1886)

[2]

Ishii T, Miyagawa S, Taguma I. Research and development on the hydrodynamic pressure generation between contacting flat surfaces. ASLE Trans 29(3): 339–346 (1986)

[3]

So H, Chen C H. Effects of micro-wedges formed between parallel surfaces on mixed lubrication—Part I: Experimental evidence. Tribol Lett 17(3): 513–520 (2004)

[4]

Ayadi K, Brunetière N, Tournerie B, Maoui A. Experimental and numerical study of the lubrication regimes of a liquid mechanical seal. Tribol Int 92: 96–108 (2015)

[5]

Bulut D, Bader N, Poll G. Cavitation and film formation in hydrodynamically lubricated parallel sliders. Tribol Int 162: 107113 (2021)

[6]
Lubbinge H. On the lubrication of mechanical face seals. Ph.D. Thesis. The Netherlands: University of Twente, 1999.
[7]

Minet C, Brunetière N, Tournerie B. On the lubrication of mechanical seals with rough surfaces: A parametric study. P I Mech Eng J-J Eng 226(12): 1109–1126 (2012)

[8]

Brunetiere N. The lubrication regimes of mechanical face seals. Appl Mech Mater 630: 255–266 (2014)

[9]
Bulut D. Cavitation and film formation in hydrodynamically lubricated parallel sliding contacts. Ph.D. Thesis. Hannover (Germany): Leibniz Universität Hannover, 2021.
[10]

Christensen H. Stochastic models for hydrodynamic lubrication of rough surfaces. Proc Inst Mech Eng 184(1): 1013–1026 (1969)

[11]

Patir N, Cheng H S. An average flow model for determining effects of three-dimensional roughness on partial hydrodynamic lubrication. J Lubr Technol 100(1): 12–17 (1978)

[12]

Patir N, Cheng H S. Application of average flow model to lubrication between rough sliding surfaces. J Lubr Technol 101(2): 220–229 (1979)

[13]

Han Y X, Lu Z Y. A two-scale methodology on modelling surface topography by homogenization technique. Appl Math Model 120: 115–131 (2023)

[14]

Lukkassen D, Nguetseng G, Wall P. Two-scale convergence. Int J Pure Appl Math 1(1): 35–86 (2002)

[15]

Bayada G, Ciuperca I, Jai M. Homogenized elliptic equations and variational inequalities with oscillating parameters. Application to the study of thin flow behavior with rough surfaces. Nonlinear Anal-Real 7(5): 950–966 (2006)

[16]

Almqvist A. Homogenization of the Reynolds equation governing hydrodynamic flow in a rotating device. J Tribol 133(2): 021705 (2011)

[17]

Skaltsas D, Rossopoulos G N, Papadopoulos C I. A comparative study of the Reynolds equation solution for slider and journal bearings with stochastic roughness on the stator and the rotor. Tribol Int 167: 107410 (2022)

[18]

Lebeck A O. Parallel sliding load support in the mixed friction regime. Part 2: Evaluation of the mechanisms. J Tribol 109(1): 196–205 (1987)

[19]

So H, Chen C H. Effects of micro-wedges formed between parallel surfaces on mixed lubrication—Part II: Modeling. Tribol Lett 19(2): 83–91 (2005)

[20]

Wang W, He Y Y, Zhao J, Mao J Y, Hu Y T, Luo J B. Optimization of groove texture profile to improve hydrodynamic lubrication performance: Theory and experiments. Friction 8(1): 83–94 (2020)

[21]

Etsion I. Modeling of surface texturing in hydrodynamic lubrication. Friction 1(3): 195–209 (2013)

[22]

Qiu Y, Khonsari M M. Performance analysis of full-film textured surfaces with consideration of roughness effects. J Tribol 133(2): 021704 (2011)

[23]

Ma C B, Duan Y J, Yu B, Sun J J, Tu Q A. The comprehensive effect of surface texture and roughness under hydrodynamic and mixed lubrication conditions. P I Mech Eng J-J-Eng 231(10): 1307–1319 (2017)

[24]

Gu C X, Meng X H, Xie Y B, Zhang D. Mixed lubrication problems in the presence of textures: An efficient solution to the cavitation problem with consideration of roughness effects. Tribol Int 103: 516–528 (2016)

[25]

Bayada G, Martin S, Vázquez C. Two-scale homogenization of a hydrodynamic Elrod–Adams model. Asymptotic Anal 44(1–2): 75–110 (2005)

[26]

Han Y X, Meng Q G, de Boer G. Two-scale homogenization of hydrodynamic lubrication in a mechanical seal with isotropic roughness based on the Elrod cavitation algorithm. P I Mech Eng J-J-Eng 236(3): 359–385 (2022)

[27]

Brunetière N, Francisco A. Lubrication mechanisms between parallel rough surfaces. Tribol Lett 67(4): 116 (2019)

[28]

Wang Y C, Azam A, Zhang G L, Dorgham A, Liu Y, Wilson M, Neville A. Understanding the mechanism of load-carrying capacity between parallel rough surfaces through a deterministic mixed lubrication model. Lubricants 10(1): 12 (2022)

[29]

Pérez-Ràfols F, Larsson R, Lundström S, Wall P, Almqvist A. A stochastic two-scale model for pressure-driven flow between rough surfaces. Proc R Soc A Math Phys Eng Sci 472: 2190 (2016).

[30]

Waseem A, Guilleminot J, Temizer. Stochastic multiscale analysis in hydrodynamic lubrication. Int J Numer Meth Eng 112(8): 1070–1093 (2017)

[31]

Pérez-Ràfols F. A two-scale stochastic model for the contact mechanics of rough surfaces including a wide span of length scales. Tribol Int 185: 108502 (2023)

[32]

Nyemeck A P, Brunetière N, Tournerie B. A multiscale approach to the mixed lubrication regime: Application to mechanical seals. Tribol Lett 47(3): 417–429 (2012)

[33]

Greenwood J A, Williamson J B P. Contact of nominally flat surfaces. P Roy Soc A-Math Phy 295(1442): 300–319 (1966)

[34]

Persson B N J. On the fractal dimension of rough surfaces. Tribol Lett 54(1): 99–106 (2014)

[35]

Hu Y Z, Tonder K. Simulation of 3-D random rough surface by 2-D digital filter and Fourier analysis. Int J Mach Tool Manu 32(1–2): 83–90 (1992)

[36]
Anderson G W, Guionnet A, Zeitouni O. An Introduction to Random Matrices. Cambridge (UK): Cambridge University Press, 2010.
[37]

Elrod H G. A cavitation algorithm. J Lubr Technol 103(3): 350–354 (1981)

[38]

Almqvist A, Fabricius J, Larsson R, Wall P. A new approach for studying cavitation in lubrication. J Tribol 136(1): 011706 (2014)

[39]

Minet C, Brunetiere N, Tournerie B, Fribourg D. Analysis and modeling of the topography of mechanical seal faces. Tribol T 53(6): 799–815 (2010)

[40]

Campañá C, Müser M H. Contact mechanics of real vs. randomly rough surfaces: A Green’s function molecular dynamics study. Europhys Lett 77(3): 38005 (2007)

Friction
Article number: 9441015
Cite this article:
Català P, Marc V-M, Pérez-Ràfols F. Roughness induced variation as a new mechanism for hydrodynamic lubrication between parallel surfaces. Friction, 2025, 13(4): 9441015. https://doi.org/10.26599/FRICT.2025.9441015
Metrics & Citations  
Article History
Copyright
Rights and Permissions
Return