音圈电机喷油器的喷雾特性试验

Effects of ambient pressure, fuel temperature and injection duration on the macro spray characteristics of a voice coil motor(VCM) injector were experimentally studied using high-speed backlit imaging technology in a constant volume combustion vessel. The results show that, spray morphology exhibits a standard hollow cone shape with clear jet-string structure distributed downstream of the spray surface under sub-atmospheric conditions. Under high ambient pressure, spray mainstream is strongly squeezed and a large-scale counter-rotating vortex( CRV) is generated on the periphery of spray mainstream. When the fuel temperature increases from 30℃ to 70℃, the spray morphology and macro characteristics show no significant change. Increasing of voice coil motor injector driving voltage substantially reduces spray breakup length. When the injection duration is less than 2.0 ms, noticeable collapse occurs downstream of spray. When the injection duration is larger than 3.0 ms, spray process and ultimate stable shape of the spray no longer change significantly.