电 控 单 体 泵 多 泵 供 油 系 统 压 力 波 动 和 一 致 性 研 究

In order to solve the problem of poor fuel supply consistency due to pressure fluctuations in the low-pressure fuel tube of the electronic unit pump(EUP) fuel supply system for diesel engines， the simulation model of an EUP single-pump and multi-pump fuel supply system was established using AMESim. And the effect of the diameter of the low-pressure fuel inlet and return tubes， throttle orifice structural parameters and damping valve structural parameters on pressure fluctuations of the fuel tube were investigated. The results show that the larger the diameter of the fuel tube is，the more inclusive the fuel pipe is to the internal fuel，and the smaller the pressure fluctuation inside the pipe will be. The optimal diameters of the main and sub-tubes were 12 mm and 8 mm respectively. The resistance of the fuel flow increases while the pressure fluctuation decreases by adding throttle holes. However，too small aperture will lead to insufficient fuel supply while too large aperture will reduce the throttling effect. Therefore，the optimal aperture diameter was set to 2. 5 mm. The damping valve plays a role in throttling，on the other hand，it makes the kinetic and potential energy of the fuel convert into the elastic potential energy of the spring，and ultimately the pressure fluctuations in the fuel tube decrease. The optimal aperture diameter and spring stiffness were set to 2. 5 mm and 25 N/mm，respectively. Based on the above optimization scheme，the amplitude of pressure fluctuation was reduced from 0. 47 MPa to 0. 18 MPa，and the fuel supply characteristics and the consistency of the multi-pump fuel supply system were also improved.