Experimental and Theoretical Approaches to Thin Film Lubrication Problems

The last fifty years have seen tremendous advances in the field of thin film lubrication. This is particularly true of steady-state Elastohydrodynamic lubrication (EHL) where the accurate measurement of film thickness combined with advanced numerical modelling methods has been very successful. However there are still many challenges to be faced in areas of practical importance for example transient operation, rough surfaces, lubricant failure and two-phase fluids. Such systems present many experimental problems and it is often difficult to obtain detailed measurements of film formation under such conditions. This insight is essential if we are to develop physically realistic models to describe these processes and predict lubrication performance. The aim of this paper is to report on the continued development of experimental methods to study thin film lubrication and to compare the results from this work to current models. The paper will also discuss the limitations of the existing experimental and modeling capabilities and the new challenges to be tackled.

[1]  Duncan Dowson,et al.  A theoretical analysis of the isothermal elastohydrodynamic lubrication of concentrated contacts. I. Direction of lubricant entrainment coincident with the major axis of the Hertzian contact ellipse , 1985, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[2]  Hugh Spikes,et al.  Oscillations induced in EHD film thickness by a step in entrainment speed , 2003 .

[3]  Motohiro Kaneta,et al.  Surface roughness in elastohydrodynamically lubricated contacts , 2000 .

[4]  H. Moes,et al.  Paper VI(i) Solving Reynolds' equation for E.H.L. line contacts by application of a multigrid method , 1987 .

[5]  Hugh Spikes,et al.  Thick‐boundary‐film formation by friction modifier additives , 1999 .

[6]  Roland Larsson,et al.  A Hybrid Film Thickness Evaluation Scheme Based on Multi-Channel Interferometry and Contact Mechanics , 2000 .

[7]  R. Gohar,et al.  Optical Measurement of Oil Film Thickness under Elasto-hydrodynamic Lubrication , 1963, Nature.

[8]  G. Dalmaz,et al.  Film Thickness in Starved EHL Point Contacts , 1998 .

[9]  Hugh Spikes,et al.  Fractionation of liquid lubricants at solid surfaces , 1996 .

[10]  D. Dowson,et al.  Elasto-hydrodynamic lubrication : the fundamentals of roller and gear lubrication , 1966 .

[11]  D. Dowson,et al.  Isothermal Elastohydrodynamic Lubrication of Point Contacts: Part 1—Theoretical Formulation , 1975 .

[12]  H. P. Evans,et al.  Inverse Solution of Reynolds’ Equation of Lubrication Under Point-Contact Elastohydrodynamic Conditions , 1981 .

[13]  R. Bosma,et al.  Multigrid, an Alternative Method of Solution for Two-Dimensional Elastohydrodynamically Lubricated Point Contact Calculations , 1987 .

[14]  Scott Bair,et al.  Pressure-Viscosity Behavior of Lubricants to 1.4 GPa and Its Relation to EHD Traction , 2000 .

[15]  A. Jackson,et al.  An Interferometric Study of the EHL of Rough Surfaces , 1976 .

[16]  Hugh Spikes,et al.  Measurement of Sub-Nanometer Lubricant Films Using Ultra-Thin Film Interferometry , 2003 .

[17]  Hugh Spikes,et al.  A study of parched lubrication , 1992 .

[18]  A. Cameron,et al.  Optical Analysis of Ball Bearing Starvation , 1971 .

[19]  Antonius Lubrecht,et al.  The transition between fully flooded and starved regimes in EHL , 2004 .

[20]  Hugh Spikes,et al.  The Development of a Spacer Layer Imaging Method (SLIM) for Mapping Elastohydrodynamic Contacts , 1996 .

[21]  G. Dalmaz,et al.  Starvation Phenomena in E.H.L. Point Contacts: Influence of Inlet Flow Distribution. , 1996 .

[22]  Martin Hartl,et al.  Elastohydrodynamic Film Thickness Mapping by Computer Differential Colorimetry , 1999 .

[23]  R. Gohar,et al.  Theoretical and experimental studies of the oil film in lubricated point contact , 1966, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[24]  A. Lubrecht,et al.  Numerical Simulation of a Transverse Ridge in a Circular EHL Contact Under Rolling/Sliding , 1994 .

[25]  Jérôme Molimard,et al.  Thin Film Colorimetric Interferometry , 2001 .

[26]  D. Dowson,et al.  Isothermal Elastohydrodynamic Lubrication of Point Contacts: Part III—Fully Flooded Results , 1976 .

[27]  J. A. Greenwood,et al.  Elastohydrodynamic Lubrication With Herschel-Bulkley Model Greases , 1972 .

[28]  D. Dowson,et al.  A Numerical Solution to the Elasto-Hydrodynamic Problem , 1959 .

[29]  Hugh Spikes,et al.  The Measurement and Study of Very Thin Lubricant Films in Concentrated Contacts , 1991 .

[30]  Y. Chiu.  An Analysis and Prediction of Lubricant Film Starvation in Rolling Contact Systems , 1974 .

[31]  T. F. Conry,et al.  A Reynolds-Eyring Equation for Elastohydrodynamic Lubrication in Line Contacts , 1987 .

[32]  Hugh Spikes,et al.  The development and application of the spacer layer imaging method for measuring lubricant film thickness , 2001 .

[33]  Motohiro Kaneta,et al.  Behaviour of point contact EHL films under pulsating loads , 2003 .

[34]  Hugh Spikes,et al.  Boundary Film Formation by Lubricant Base Fluids , 1996 .