Air-assisted ultrasonic atomization

We have established a correlation between the drop diameter with peak volume-percent of the drop-size distribution obtained in ultrasonic atomization and the wavelength of the capillary waves determined by the ultrasonic frequency in accordance with the Kelvin equation. The amplitude growth rates of these capillary waves are calculated based on Taylor´s theory of temporal instability of wind generated capillary waves. The resulting dispersion curves yield predictions in remarkable agreement with experimental results regarding the effects of air velocity on drop-size distributions in air-assisted ultrasonic atomization. Hence, we conclude that atomization by high-velocity air occurs via the same mechanism as ultrasonic atomization, Taylor-mode break-up of capillary waves in particular. In addition, uniform drops in diameter determined by the ultrasonic frequency can be obtained by adjusting the air velocity