Theoretical determination of treating modes providing the formation of high-disperse aerosol at two-stage ultrasonic atomization

摘要

The article is devoted to theoretical researching of process of two-stage high-disperse atomization of liquids including the process of primary formation of large drops at ultrasonic (US) action on thin film of liquid and further disintegration of drops under action of high-frequency ultrasonic field in air-drop medium. It was found the physical principle and it was offered the mathematical model of droplets disintegration allowing to determine the threshold levels of sound pressure at different sizes of drops, features of atomizing liquid and types of action. It was defined that most effective method of ultrasonic action providing disintegration of droplets is in radiating of sequence of pulses of different frequency at high concentration of aerosol (more than 10 vol. %) providing the conditions for intermodal dispersion. It was shown that at the acting of continuous single frequency vibrations the threshold level of sound pressure required for drop disintegration can exceed 190 dB. At the pulsing treatment the required level of sound pressure decreases to 155...160 dB in continuous air medium.