Nano-lubricant film formation due to combined elastohydrodynamic and surface force action under isothermal conditions

This paper presents the results of numerical prediction of the lubricant fi lm thickness and pressure distribution in concentrated counterformal point contact under isothermal conditions. The operating conditions, which includ e load and speed of entraining motion, promote the formation of ultra-thin films; these are formed under the combined action of elastohydrodynamic lub rication (EHL), the surface contact force of solvation and molecular intera ctions due to the presence of Van der Waals forces. A numerical solution ha s been carried out, using the low-relaxation Newton-Raphson iteration techn ique, applied to the convergence of the hydrodynamic pressure. The paper sh ows that the effect of surface forces become significant as the elastic fil m (i.e. the gap) is reduced to a few nanometres. The numerical predictions have been shown to conform well to the numerical work and experimental find ings of other research workers.