Atomization and Sprays, Vol.31, No.8, 81-99, 2021
EFFECT OF CONCENTRATION OF DROPLETS IN AN AEROSOL CLOUD ON THE NUMBER AND OUTCOMES OF THEIR COLLISIONS IN A GAS MEDIUM
The paper presents experimental research findings for the conditions and characteristics of the collisions of liquid droplets in an aerosol cloud when varying their concentration. Threshold concentrations have been established, above which the number of droplet collisions remains almost unchanged, i.e., the particle size distribution of the aerosol cloud is retained. The results of the comprehensive assessment are presented for the influence that the ratio of droplet dimensions, droplet concentration, Weber number, and the angular and linear interaction parameters jointly have on the collision frequency. A general approximation has been obtained to predict the number of liquid droplet collisions. This equation can help to determine the parameters of aerosol miscibility and provide the necessary dimensions of droplets, considering their collisions with each. Four interaction regimes have been identified: bounce, separation, coalescence, and disruption. The frequency of their occurrence has been determined for various droplet concentrations and collision conditions. Conditions have been shown that ensure a steady distribution of droplets in the aerosol cloud.