MODELING AND SIMULATION OF ELASTOHYDRODYNAMIC (EHD) LUBRICATION OF PISTON RINGS

Abstract

An optimum design of an automobile engine is of crucial importance to automobile industry for both civil and defense applications. In automobile systems, an engine is considered to be the heart of an automobile and affects the overall performance of a vehicle. Passenger cars and commercial vehicles have mechanically operated engine driven oil pumps to lubricate all critical moving components of an engine. The main aim of a lubricant is to reduce/ minimize all forms of friction and wear during normal engine operation leading to a smooth operation and to enhance life of an automobile engine. The sliding motion of piston and its rings (slider bearings) accounts for 45% of total friction and wear in an engine. A piston in a cylinder cannot seal the cylinder effectively. This job is done by the piston rings. Properly constructed and fitted rings rub against the cylinder wall with good contact all around the cylinder. Rings ride in grooves that are cut into the piston head. In this research work, modeling and simulation of Elastohydrodynamic (EHD) lubrication film regime between rings and engine cylinder walls will be carried out to evolve an optimum design through parametric studies. The predicted results would be compared with those based on experimental investigation.