Effect of In-Cylinder Flow on Formation of Stratified Mixture in a 4-Valve Optical Engine

Abstract

In this study, we have examined the effect of in-cylinder flow on the formation of stratified charge. To make a stratified charge, we used a 4-valve optical engine with two intake ports. The air with oil mists was supplied through two intake ports with different flow rates and mist concentrations. A cross-correlation PIV technique was applied to measure in-cylinder flow. From the measurement of tracer concentration and in-cylinder flow, it was made clear that the swirling flow and the spatial variation of air flow played an important role in the charge homogeneity.