A poppet type nozzle which promotes atomization by utilizing cavitation phenomena was designed to clarify the atomization mechanism. The configuration of the nozzle which has two orifices and an intermediate cavity between the orifices was decided by numerical analysis on the cavitating flow in the nozzle. In this report, atomization mechanism and spray characteristics of the nozzle are described. The following results are obtained: (1) The net-like fuel liquid sheet is observed closed to orifice. The net-like structure with cavitation bubbles is collapsed to droplets via ligaments. (2) The present nozzle has the features of generating smaller drop size and lower spray tip penetration than the conventional poppet type nozzle.
