Study on Effect of Heat Transfer Space Non-Uniformity of Combustion Chamber Components on In-Cylinder Spray in Diesel Engine

Combustion chamber components(cylinder head-cylinder liner-piston assembly-oil film) were treated as a coupled body.A coupled three-dimensional calculation model for in-cylinder working process and the combustion chamber components was built with domain decomposition and boundary coupling method,which adopts the coupled three-dimensional simulation of in-cylinder working process and the combustion chamber components.The influence of the space non-uniformity in heat transfer among combustion chamber components on in-cylinder spray is conducted.The results show that the space non-uniformity in heat transfer among the combustion chamber components has certain influence on fuel atomization at the initial and middle stage of spray,mainly in the bottom space of combustion chamber and near cylinder wall.At late stage of spray,the in-cylinder gas temperature is mainly dependent on fuel combustion, rather than on heat transfer of cylinder wall.Thus,wall temperature space no-uniform temperature distribution of combustion chamber components of wall space has little influence on spray.