Two-Dimensional Piston Ring Lubrication—Part I: Rigid Ring and Liner Solution

Abstract

A two-dimensional elastohydrodynamic cavitation algorithm is developed for piston ring lubrication. The nonlinear governing equation derived from the Reynolds equation to include cavitation and elastohydrodynamics is linearized for numerical efficiency. An elliptic cylinder liner and rigid ring are considered to investigate circumferencial flow effects which have been ignored in previous studies. The hydrodynamic pressure distribution and film thickness at various crank angles are determined. Results for a typical automotive engine show that the elliptic liner causes a dramatic drop in the hydrodynamic pressure and reduces the film thickness. It is found that the pressure reformation effect cannot be neglected when the piston ring moves away from the top dead center (TDC).