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Fluid film bearings are machine elements that should be studied within the broader context of tribology. The three subfields of tribology - friction, lubrication, and wear - are strongly interrelated. The last decade has witnessed significant advances in the area of fluid film lubrication and its applications, and this second edition offers a look at some of these advances. This edition adds to the fundamentals of fluid film lubrication, a discourse on surface effects and the inclusion of treatment of flow with significant inertia within the section on turbulence. Basic ideas of the multigrid method are conveyed along with multilevel multi-integration in the treatment of elastohydrodynamic lubrication. New chapters have been included on ultra-thin films, both liquid and gaseous, and lubrication of articulating joints and their replacement. Some of the most recent literature is discussed.

Fluid film bearings are among the best devices for overcoming friction and eliminating wear. They are machine elements and, together with shafts, gears, and cams, constitute the building blocks engineers use in the design and construction of mechanical devices. This book offers a systematic treatment of the fundamentals of fluid film lubrication and fluid film bearings. The introduction places fluid film bearings within the broader context of tribology, a subject that encompasses friction, lubrication, and wear. The early chapters provide a thorough discussion of classical tribological theory. The remainder of the book is devoted to more advanced topics of inertia, thermal and turbulence effects, lubrication of counterformal contacts, and non-Newtonian lubricants. Also included are developing areas, such as lubrication with emulsions. Graduate and senior undergraduate students, researchers, and practising engineers will appreciate this clear, thorough discussion of fluid film lubrication and fluid film bearings.

Reynolds's lubrication approximation, one of the cornerstones of°uid mechanics, is constructed on the assumption that the viscosity is independent of the pressure. This assumption is reasonable at low pressures and is appropriate for a large class of applications. However, in an important instance that appeals to the approximation (elastohydrodynamic lubrication (EHL)), the liquid lubricant is subjected to extremely high pressures and the assumption that the viscosity is independent of the pressure no longer holds. On the contrary, pressure dependence of viscosity is severe and the viscosity can increase by several orders of magnitude due to pressure increase. Nevertheless, in the current literature the pressure dependence of viscosity in the derivation of the governing equations for EHL is only recognized a posteriori, that is, after the Reynolds equation has been stated under the assumption of constant viscosity.A consistent derivation of the equations of EHL that takes into account the pressure dependence of viscosity right from the outset leads to additional and hitherto neglected terms in the governing equations. Consequently, construction of a single pressure equation, analogous to the Reynolds equation, is no longer possible without additional, drastic, assumptions.In this study, we provide a consistent derivation of the equations of motion for EHL and, with additional, simplifying assumptions, derive a modi¯ed Reynolds equation. We then provide a comparison between the solutions to the classical equation of Reynolds's and our modi¯ed equation. The modi¯ed equation results in slightly higher pressures, but at signi¯cantly higher viscosities, than the classical Reynolds equation.

An attempt is made to formulate a thermohydrodynamic model of film lubrication, that is valid in both laminar and superlaminar flow regimes. The model represents turbulence by eddy diffusivities and, in the manner of Ng and Pan, considers the flow to be a small perturbation of turbulent Couette flow. The energy equation retains heat conduction in the direction of sliding motion, thus making the analysis applicable even at large eccentricities when backflow of the lubricant occurs. The equations are solved by finite element methods. Theoretical predictions are compared with two sets of experimental data, one set hitherto unpublished.