Modeling And Simulation Of Electronic Unit Pump Fuel Injection System For Diesel Engine

The electronic control fuel injection system is an effective way to achieve theenergy-saving emission reduction of diesel engine. The electronic unit pump fuelinjection system with high injection pressure and good reliability has become one of the idealchoices for high power diesel engine. In order to ensure the fuel injection system possessgood spraying characteristics, it is necessary to optimize and match the structural parameters ofthe fuel injection system before the transformation of diesel engine electronic control.In this paper, a systematic mathematical models of the fuel injection system of4190electronic unit pump diesel engine is established and a simulation model of WP2000electronicunit pump injection system is also established, employing AMESim simulation software.Theaccuracy of the simulation model is verified with the experimental data of fuel injectioncharacteristics, and the influence factors, the optimal matching of structural parameters (camvelocity, the diameter of the plunger, fuel injector aperture, length of high pressure fuel pipe) areanalyzed.Through the analysis, the conclusions are as follows:(1)The established injection system simulation model can accurately predicts the fuelinjection law after the verification with the experimental data of fuel injection characteristics.The simulation curve of injection pressure and injection velocity substantially coincide with theactually measured curves.(2) Among the structure parameters of EUP, cam velocity, the diameter of the plunger andthe change of fuel injector aperture have obvious effects on injection pressure and injectionvelocity; whereas the length of high pressure fuel pipe has little effect on fuel injection system.The higher speed of the cam velocity, the higher injection pressure and the larger quantities ofinjection.As the plunger diameter increases, the injection delay decreases, with theinjection velocity increasing and then the injection pressure increases accordingly. With thediameter of nozzle hole reducing, the injection velocity also decreases, whereas the the injectionpressure increases and the injection duration increases accordingly.(3) Combined with the transformation goals of EUP, two groups of structuralparameters optimization schemes named850-0.46-26-14.5and850-0.46-24-14were worked out,through the optimal matching analysis of the fuel injection system parameters (cam velocity, thediameter of the plunger, fuel injector aperture, length of high pressure pipe), which provides abasis for the matching of4190diesel engine fuel injection.