Investigating Effects of Different Influence Factors on the Dynamic Response of a Common-Rail Injector 2019-01-0272
The electrical control common-rail injection system is a key part for the marine diesel engine. In this article, a detailed fluid-mechanical-electric-magnetic coupling mathematic model about the common-rail injection system was established, with considering the transient of fuel properties, different structure parameters of the injector and the nonlinear magnetization and magnetic saturation of the magnetic materials of the high-speed solenoid valve (HSV) for the common-rail injector. This model was verified through comparing the calculations of needle lift and injection rate with the experiment data at different injection pressures, and good consistencies could prove this model is correct. Based on this model, the effect of different factors on the dynamic response of the injector was investigated to prepare for the optimization. The results demonstrated the different structure parameters of the injector, such as diameters of inlet/outlet of control chamber, needle lift, needle diameters, etc influenced the injection with varying degrees. Dynamic response of the HSV was very important, as its control precision and response time was relevant to the injection control. A high voltage could open the HSV quickly, while it takes longer time to drop to zero and close the HSV, also, the eddy current should be considered for its resistance effect, therefore, a reasonable driving strategy is necessary. Establishing a detailed mathematic model is helpful to study the influence of different factors, and an effective optimum design for an injector and its HSV would be proposed in detail.
Jianhui Zhao, Pengfei Yue, Kebiao Wei, Leonid Grekhov
Harbin Engineering University, Bauman Moscow State Technical University