Study on the free edge effect on finite line contact elastohydrodynamic lubrication

This paper incorporated a recently developed algorithm, which directly gives the elastic deformation of loaded quarter-space (QS) bodies, into a finite line contact elastohydrodynamic lubrication (EHL) analysis. Half-space (HS) and QS models were adopted in the analysis and the results were compared with the data obtained from conventional optical EHL tests of steel rollers on a glass disc. This study found that contact deformation was dominated by glass disc deformation. Thus, the use of a steel roller on a glass disc in conventional optical EHL technique is not appropriate for studying the free edge surface effect. Free edge surfaces reduce the magnitude of pressure spikes near the ends of contact. Rollers with different end profiles were also evaluated. •Free edge effect on finite line contact EHL was studied.•Two contact types, roller on (i) semi-infinite plane and (ii) a plane of same width were considered.•Free edge is beneficial to reduce the pressure spikes near roller end.•Optical EHL test using steel roller-glass disc contact is not suitable for the study of the edge effect.•The optimal roller profiles were suggested.