부산대학교 도서관

In view of the problem where the fuel injection quantity of a certain type of fuel injectors decrease with the increase of rail pressure during the independent research and production of GDI fuel system, the effects of injector needle valve diameter, needle valve lift and opening voltage on injector injection laws under different injection pressures were analyzed based on the simulation model of GDI engine fuel system established by AMESim software. The simulation results show that with the increase of the needle valve diameter and the injection pressure, the power of the original driving coil was insufficient, and the dynamic flow response characteristics of the injector become worse. Increasing the driving current and starting voltage has limited effect on improving the performance of the injector. Although the injector can be fully opened, there is still a significant opening delay. The dynamic flow response characteristics of the injector can be improved by increasing the number of turns in the coil and increasing the power of the driving coil. At the same time, the needle valve lift of the injector can be appropriately increased to meet the demand of increasing the injection amount.