FRICTION BETWEEN PISTON RING AND LINER IN I.C. ENGINE

In IC engine piston ring friction losses account for approximately 20% of total mechanical losses as reported in the literature. A reduction in piston ring friction would therefore result in higher efficiency, lower fuel consumption and reduced emissions. To reduce these losses, various parametric approaches are made particularly at design stage and experimental level. The goal of this study was develop lubricants to improve engine efficiency, without adversely affecting oil consumption, blow by, wear and cost. The variable parameters are piston velocity, engine speed, oil viscosity, gas pressure, crank angle film thickness and coefficient of friction. Non variable parameter are system constant, bore diameter, ring tension, ring width, compression ratio, reciprocating mass, piston ring area and piston ring profile. The major assumptions for developing models are either hydrodynamic lubrication theory of Reynolds equation or boundary lubrication theory. Paper shows the effect of different lubricants i.e. SAE 2T, SAE 4T, SAE 20W40 on friction force acting between the piston rings and cylinder liner of IC engine