Simulation And Analysis Of Common-rail Injection System In Diesel Engine

This paper introduces the development of electronically controlled technology and the types of electronically controlled fuel injection, systems of diesel engines , analyses how three injection systems (position control, time control, pressure and time control) work and the characteristics and keys of electronically controlled technology . This paper explains the merits and shortcomings of three systems , points out that the electronic controlled common rail injection system is the development trend of injection system . These systems have the characteristics that the fuel injects with high pressure , and the fuel injection pressure , fuel injection timing and fuel injection velocity can be controlled flexibly .Accordingly , the flexibility and precision of the system control are improved enormously . The electronic controlled common rail injection system is the main development direction of the diesel engines injection system in the future.This paper analyses the injector structure and the characteristics of injection of the electronically controlled accumulator type common rail fuel injection system , and simulates it by using a software HYDSIM. In the system , the establishment of high pressure and the injection of high pressure oil is separated completely in time . By improving injector structure and changing the parameters of the injector , we can implement the pilot injection and realize the high pressure injection , and the fuel injection quantity , fuel injection pressure and fuel injection timing can be controlled flexibly .This may be an effective way to optimize diesel combustion process , decrease emission and improve fuel economy . By improving the injector , we can implement the pilot injection with ideal injection model .This paper simulates the electronically controlled common rail injection system by using professional software , and it also is the first time to test it with experiments and analysis the system in detail .