CONTROL OF MEAN DROPLET DIAMETER ISSUED FROM Y-JET-TYPE AIRBLAST ATOMIZER BY USING FLUID-AMPLIFIER

A new type of atomizer has been developed to control mean droplet diam eter over a wide range of liquid flow rates; this newly developed atom izer of Y-jet type employs a fluid amplifier to control the liquid flo w rate. The liquid flowing into the atomizer is distributed by a fluid amplifier into two ports with different inner diameters. During the p resent experiments, the liquid flow rate was varied over a turndown ra tio of 7, while the air flow rate was kept constant. Generally, the me an droplet diameter is greatly influenced by the atomizing air velocit y, and the mean diameter decreases steadily as the atomizing air veloc ity increases. In the proposed method, to keep the mean diameter const ant, the liquid flowing into smaller ports where high-speed air passes is greatly increased with total liquid flow rate. On the other hand, liquid flowing into larger ports, where low-speed air passes through, is gradually increased Consequently, the mean droplet diameter changes only 10 mu m for the optimum design over the turndown ration of 7, wh ereas the mean diameter changes 30 mu m without the fluid amplifier.