Abstract
An attempt was made to establish the coalescence frequency of dispersed drops in an agitated tank. In experiments, transient drop size distributions were measured during the processes of drop coalescence after a stepwise reduction of impeller speed. The transient drop size distributions were calculated from the population balance equation for dispersed drops by applying a previously proposed equation for drop breakup and assuming some different functional forms for coalescence frequency. From comparison between calculated and experimental distributions, a functional form of coalescence frequency was determined which adequately correlates transient drop size distributions with the breakup frequency equation. It was also shown that the equations for coalescence and breakup frequencies successfully predict transient drop size distributions in drop dispersion processes.
