Analysis of Piston Frictional Force under Engine Firing Condition

- Effect of Cylinder Bore Crosshatch Angle on Friction between Piston Ring Pack and Cylinder Bore -

Abstract

A novel lubrication model has been developed which considers characteristics of crosshatched surface. The model yields flow factors using crosshatch angle, plateau ratio, and groove depth. The model is applied to the oil film between piston ring pack and crosshatched bore, which predicts increase in oil film thickness and reduction of friction mean effective pressure by 1kPa with reduction of crosshatch angle from 30°to 10°. The effect of friction reduction has been verified using test rig and floating liner engine. The reduction of crosshatch angle has also been confirmed no evil effect on lubricating oil consumption and anti-scuffing performance.