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This paper introduces an analytical approach to study the textured surfaces in hydrodynamic lubrication regime. For this purpose, a method of integrating the Reynolds equation for slider bearings with surface discontinuities is presented. By introducing appropriate dimensionless parameters, analytical relations for various texture profiles in both indented and projected forms are delivered. These relations express the nature of mathematical dependence between textured bearing performance measures and geometrical/operational parameters. An optimisation procedure is employed to achieve the optimum texturing parameters promoting maximum load capacity, load capacity to lubricant flow rate ratio and minimum friction coefficient for asymmetric partially textured slider bearings. Keywords IntroductionIt is now widely accepted that introducing artificially created micro-features onto sliding surfaces can significantly affect friction and wear of the sliding bearings. It is further believed that the textured surfaces provide the best performance amongst all other mechanical surface treatments [1]. The positive effect of artificial surface texturing on enhancing the load capacity, wear resistance and/or friction coefficient of mechanical seals [2], piston-ring/cylinder liner mechanism in internal combustion engines [3,4,5] and roller/piston in hydraulic motors [6] as some of the application examples are shown through numerical and/or experimental studies.Considering the associated theoretical studies, in a pioneering work by Salama [7], the effect of macro-roughness induced by manufacturing process in the form of surface waviness on the slider bearing performances was studied. As a result, existence of an optimum waviness length to amplitude was reported. By developing a theoretical model to obtain pressure distribution for a single micro-asperity and then, spreading the results for a population of asperities mounted on a radial face seal, Hamilton et al [8] notified existence of an optimum range for asperity height and asperity area fraction providing the maximum loads support. They suggested further research on the effect of interactions amongst asperities. On the other hand, an analytical/experimental study on microasperity lubrication by Anno et al [9] proposed that the poorer correlation between experimental and theoretical results in [8] could be improved by considering the hydrodynamic load support induced by small tilts on the tops of asperities. Later on, Anno et al [10] extended the study to 'negative asperities' and concluded that although all shape of asperities (whether positive or negative) of comparable dimension produce similar load support, to avoid leakage, one must utilise negative asperities.The study of tribological effects obtained by introducing surface microfeatures was brought to the centre of attention again by Etsion and Burstein [11] who focused on the study of the effect of shallow pores on the operational behaviour of the mechanical face seals. They solved the Reynolds equation numer...

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