Diesel Engine Used The Domestic Common Rail System And Technology Route EGR+DOC+POC To Meet The Country â…£ Standard

Currently, the main stream fuel injection control systems in Yuchai’s diesel engines are BOSCH common rail system, DELPHI unit pump, DELPHI common rail system, Witt and Nanyue unit pump. The domestic common rail system is a newly developed one to break out the foreign monopoly and to reduce the cost of the control systems and the key components of diesel engines. This paper took Yuchai 6A-48 models to install the domestic common rail system and study its feasibility against to other control systems.Diesel exhaust contains harmful pollutants such as NOx, PM, HC, CO, etc., NOx and PM are the main pollutants which shall be controlled according to the emission regulations. The hot EGR control was applied in Yuchai 6A-48 diesel engine and its design and configuration were optimized. Then DOC and POC were included to implement national IV regulations.This paper summarized the composition of domestic common rail system with an comparison with other common rail systems. The generation, hazard and influencing factors of diesel engine emissions of pollutants were described. Then the current popular aftertreatment technology, such as DOC, POC, DPF, SCR, was introduced. According to these, the exhaust catalyst selection was determined for YC6A-48 diesel engine. Considering the economic costs and the satisfaction of the regulatory requirements, YC68-48 diesel engine used technology route EGR + DOC + POC to meet the country Ⅳ standard ultimately. Additionally the optimization of engine configuration, calibration of electronically controlled data and matching of aftertreatment system application were conducted to ensure the diesel model to meets the national IV emission requirements. This paper analysis the feasibility of the project based on the target, the prospect of the project, the whole layout design, the main performance analysis, and the commercialization. The main work and innovations of the thesis are as follows:(1) By comparing the BOSCH common rail system and fuel system of the core components of control system, the domestic common rail fuel system and electric control system of key parts from the Angle of design can meet the use requirements, meet the conditions for replacement of BOSCH common rail system.And, through the actual verification and reliability of oil pump test bench, confirmed that the domestic common rail system meet the demand of development.(2)Completed the EGR arrangement, selection and related parts design, completed the development of new system of engine combustion test plan, determine the power of the engine combustion basic configuration and the suitable period.(3) verall scheme is determined, the domestic common rail system applying EGR, DOC and POC technical route to the country Ⅳ standard, to determine the feasibility of this technology scheme discharging standard.(4) Compared the SCR model and EGR model in design, performance, production and application of the difference, and the subsequent improvement and development provides a theoretical and practical reference value.