An analytical model is developed to study the potential use of partial laser surface texturing (LST) for reducing the friction between a piston ring and cylinder liner. The hydrodynamic pressure distribution and the time-dependent clearance between the piston ring and cylinder liner are obtained from a simultaneous solution of the Reynolds equation and the ring equation of motion in the radial direction. The time behavior of the friction force is calculated from the shear stresses in the viscous fluid film and the time-dependent clearance. An intensive parametric investigation is performed to identify the main parameters of the problem. The optimum LST parameters such as dimples depth, texture area density, and textured portion of the nominal contact surface of the piston ring are evaluated.

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The present study focuses on modeling the effect of elastomer surface texturing in soft elasto-hydrodynamic lubrication. The model consists of an elastomer with spherical microdimples sliding at a constant velocity relative to a rigid and smooth counterpart in the presence of viscous lubricant. The hydrodynamic lubrication and the elasticity problems are solved simultaneously for the cases of full and partial texturing of the elastomer surface. Load carrying capacity and friction force are evaluated by integration of the pressure and shear stress fields in the viscous lubricant, respectively. A parametric analysis is performed to obtain the optimum surface texturing parameters for maximum load and minimum friction.

A soft elastohydrodynamic lubrication (SEHL) model is presented that consists of a stationary surface-textured soft elastomer sleeve and a rigid, smooth rotating shaft. The Reynolds equation and the equation of linear elasticity are solved simultaneously for the pressure distribution and viscous shear stresses in the fluid film and for the elastic stresses and deformations in the elastomer. An extensive parametric analysis is performed to evaluate the optimum parameters of the surface texturing for minimum friction coefficient. The transition from full hydrodynamic to mixed lubrication is also analyzed. It is shown that the model is also valid for predicting friction coefficient of various types of circumferential elastomer seals.