Effects Combustion Chamber Geometries And Nozzle Parameters On Combustion Characteristics

Vehicle engine is in the direction of diesel engine, as it has the characteristics of high efficiency and energy saving. The shape of combustion chamber and the parameters of nozzle have decisive influence on the mixture formation and combustion process. Reasonable combustion chamber geometries and nozzle parameters play an important role in getting nice economy and low emissions of diesel engine.LD1110DI single cylinder diesel engine is the base of this article.It researches cylinder flow field state of different combustion chamber shapes under different number of orifices and different injection angle. The research works of this paper are as follows:(1) The modeling software UG is used to set plum-shaped pit piston when the LD1110type engine is eccentric arrangement. This paper devises w combustor and necking combustion chamber in the case of constant compression ratio and the combustion chamber volume. (2)Three kinds of combustion chambers temperature field were analyzed with the finite element software ANSYS. Results show that the temperature filed of the piston with the co combustion chambers and the necking combustion chamber is more uniform than the original models.(3)This paper selects four-hole and six-hole injectors which take142°,148°,154°and160°injection angle. It used the AVL-fire software to aim at with a four-hole, six-hole injectors w combustion chamber and equipped with a four-hole, six-hole injectors necking combustion chamber in the four injector angle to get the cylinder combustion simulation.(4)This paper discusses the power performance, economic performance and emissions of the simulation result. The findings are as follow:Temperature and velocity distribution in-cylinder under different spray angle is different. Fuel injection angle impact the spatial distribution of the fuel in the combustion chamber. The formation of combustion mixture combustion chamber is more favorable necking combustion chamber than w combustion chamber. The shape of the combustion chamber determines the movement of fluid in-cylinder. Four holes nozzle more NO emissions, six holes nozzle more Soot emissions. In order to make full combustion, to ensure the engine power, different shape of the combustion chamber need to meet a number of different orifice and injector angle to improved fuel economy and emissions.The influence factors of diesel engine combustion are combustion chamber shape, spray angle and spray holes number. Good combustion performance requires these factors reasonable combination. This paper’s study shows that the angle of the injector and spray the number of holes with the research, injection angle of154°in the six-hole injectors with necking combustion chamber can achieve better economy and emissions.