The Effect of In-cylinder Gas Flow and Temperature on Heat Transfer between Gas and Chamber Wall in SI Engine.

摘要

Super-lean burn Spark ignition (SI) engine, which aims to improve heat efficiency with introducing super-lean premixed gas and strong tumble flow has been studied. Low temperatures combustion caused by super-lean premixed gas decreases heat loss. On the other hand, strong tumble flow which accelerates burning velocity would increase heat loss. Therefore, these two effects on heat loss should be checked. Especially, in the low temperatures combustion, heat loss during not only around top dead center (TDC), but also other duration such as intake and exhaust stroke would be more significant than that in the stoichiometric combustion. This article researched the heat flux and heat transfer coefficient in each strokes. The effect of strong gas flow on heat flux and the coefficient was confirmed in the intake and compression stroke.