Study on Transient Fuel Hydrodynamic Force Characteristics of High-Speed Solenoid Valve for Common Rail Injector

The working process of the high-speed solenoid valve (HSV) of high-pressure common rail (CR) injector has the characteristics of electro-magnetic-mechanical-hydrodynamic multi-physical field coupling. However, most of the research work in this field is carried out without considering hydrodynamic environment of the HSV. Furthermore, the dynamic response characteristics of the transient fuel hydrodynamic force (TFHF) of the HSV should not be neglected. In this study, a three-dimensional finite element method is used to simulate the TFHF between the injector electromagnet and the armature. The results show that cavitation phenomena appears on the lower surface of the armature during the HSV opening process. The faster the armature moves up, the greater the cavitation intensity. Damping holes on the armature can reduce the TFHF acting on the upper surface of the armature; however, the armature structure with straight grooves and damping holes reduces the TFHF more evidently during the HSV opening and the inhibition effect of this structure on cavitation is more evident. The TFHF on the armature decreases with an increase in the depth of the coil groove. However, the selection of the groove depth should be considered together with the optimization of the electromagnetic force characteristics of the HSV.