Improving tribological performance of piston rings by partial surface texturing

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.