SI엔진 피스톤 결합체의 마찰력과 유막 두께 측정

Abstract

Measurement techniques were developed to quantify the instantaneous piston assembly friction force and the oil film thickness between the piston rings and the cylinder liner. That can be easily applied to small multi-cylinder production engine. The friction force and oil film thickness data were acquired under various operation conditions and for various operation conditions and for various oils in an SI four cylinder engine. In this study, friction force data were found to be more reliable in consequence of proper compensation. It was possible to measure oil film thickness on thin oil ring rails as well as compression rings. The results revealed that mixed lubrication is dominant in limited operating conditions where product of kinematic viscosity and mean piston speed is lower than 80×10-6m3/s2.