In order to understand the internal cavitation flow and near field spray characteristics of injector nozzles with internal/external intersecting holes

three types of nozzles

including two different intersecting hole nozzles and one conventional cylindrical hole nozzle were visualized by using high speed photography at different injections pressures

sub-hole impact angle and sub-hole center to center distance. Results show that

unlike the paraxial symmetric spray from the conventional cylindrical hole nozzle

the internal/external intersecting hole nozzle can create a fan shaped spray due to internal/external spray impingements. As observed

the spray from the external intersecting hole nozzle shows a very intensive radial diffusibility followed by that of the internal intersecting hole nozzles and both of which are more diffusible than that of conventional cylindrical hole nozzle. In addition

as the injection pressure increases

the conventional nozzle produces cavitation at 0.3 MPa

which rapidly develops into a hydraulic plunger flow

and the external intersecting hole nozzle also generates cavitation at 0.3 MPa

but no hydraulic plunger flow occurs at 0.1 MPa. While the internal intersecting hole nozzle has no cavitation at all.