BREAKUP OF A WATER JET IN HIGH VELOCITY CO-FLOWING AIR

Flow visualizations by high speed cameras of the disintegration of a liquid (water) jet in a high-velocity co-axial gas (air) jet allowed the classification of breakup regimes according to the Weber number and momentum ratio. A momentum criterion for the pinch-off of the liquid core and the onset of a superpulsating mode is proposed. Drop size measurements in the high momentum ratio show a dependence of the drop size on the inverse square of the gas velocity suggesting a secondary breakup mechanism.