Simulation studies on the boot shape injection of a giant magnetostrictive injector

Abstract

Giant magnetostrictive injector using giant magnetostrictive material acting an electronic controlled injector may be one new promising injector to acquire adjustable injection rates while maintaining large injection quantity. An electronic controlled injector driven by a giant magnetostrictive actuator was designed through combining the driving requirement and output characteristics of the material. To promote responding speed of the coil current, the driving voltage with open-hold-fall type waveform was employed just like using in an electromagnetic injector. Simulation model for the injection characteristic of the injector was established using AMEsim software and verified using experimental results collected by the single injection meter. From simulation and experimental results, designed giant magnetostrictive injector showed good performances as maximum spray rate of 4.5 L/min and minimum spray pulse width of 0.21 ms, and realized the boot shape injection when generated by the designed voltage wave. Furthermore, duration time and amplitude of the pilot spray part in a boot shape injection were respectively adjusted through changing the dwell time and opening time. The boot shape injection reached by the giant magnetostrictive injector can reach quite accurate control of fuel injection and then promote fuel efficiency effectively.

Analysis of Magnetic Field Characteristics of a Giant Magnetostrictive Actuator with a Semi-Closed Magnetic Circuit

“…Compared with piezoelectric materials and other traditional magnetostrictive materials, it has a large magnetostrictive strain, large output force, and fast response speed, which is widely used in precision actuation, active control, and other fields. Using GMM as the energy-transducing material to develop giant magnetostrictive actuators for injectors [4][5][6] is one of the research hotspots in recent years. With the continuous improvement of machining and manufacturing technology, many scholars [7,8] considered designing giant magnetostrictive actuators (GMAs) for direct-drive injectors.…”