THEORETICAL SPRAY PERFORMANCE OF SWIRL-TYPE NOZZLES

Theoretical spray performance of swirl-type nozzles was developed by s olving boundary flows in the swirl chamber of the nozzle using the int egral momentum method. Essential structures of the discharge coefficie nt, the swath coefficient, and the volume median diameter were derived from the theoretical investigation of fluid motion. The nozzle parame ters and average relative velocity at the discharge orifice governed t he spray performance and flow regions. Extreme conditions that sensiti vely influenced the spray performance at high and low flow rates were identified from the theoretical analysis. The theoretical spray perfor mance discussed in this study would be a basic form for the design of a variable flow swirl nozzle, and be subject to calibration for a spec ific configuration of the swirl nozzle.