Abstract
The group-hole nozzle has a series of groups of holes and each group consists of two small holes with a small spatial interval and a small angle. It is expected that the spray behavior of the group-hole nozzle has enough spray tip penetration and smaller mean droplet diameter as compared with the spray injected by the conventional multi hole nozzle having the hole area same as the group-hole nozzle. To investigate effects of the group-hole nozzle on the mixture characteristics, the extended ultraviolet and visible Laser Absorption Scattering (LAS) technique, which can be applied to a non-axisymmetric spray, was developed. Liquid and vapor phase mass distributions in the spray were obtained by the extended LAS technique. The analyses were made of the free sprays and the flat wall impinging sprays. In the case of the free sprays, the group-hole nozzle with the larger spatial interval of two holes enhances fuel evaporation though decreases the spray tip penetration. In the case of the impinging sprays, the group-hole nozzle enhances the fuel evaporation as well as the spray tip penetration.
