EFFECTS OF NOZZLE EXIT GEOMETRY ON SPRAY CHARACTERISTICS OF A BLURRY INJECTOR

This paper analyses the effects of nozzle geometry on sprays produced by a blurry injector using water as test fluid. Significant differences on the sprays formed by the injector were observed for cylindrical, conical-cylindrical, and conical nozzle exit configurations. Several operational characteristics were determined, including average droplet diameters, discharge coefficients, air-to-liquid mass ratios, and spray cone angles. Conical and cylindrical-conical nozzles have shown similar behavior and higher atomization efficiency, yielding smaller Sauter mean diameters and mass median diameters than the cylindrical nozzle. Nevertheless, they presented lower discharge coefficients and required higher air-to-liquid mass ratios, air flow rates, and air exit velocities than the cylindrical nozzle.