Experimental Study of Drop Size Distribution in the Bag Breakup Regime

The situation of a liquid drop exposed to a continuous air jet flow was investigated experimentally. The drop bag breakup of test liquids which included water, ethanol, and various glycerol mixtures was observed using a high-speed camera. The morphological change, such as drop deformation, was observed and analyzed. Mean fragment sizes were obtained, which were in good agreement with those reported in the literature. Big fragments formed from the ring contained the great mass of the initial drop and were studied in detail, and correlations on fragment mean size and number were obtained. Mean size decreased with the Weber number and increased with the Ohnesorge number; fragment number was in contrast to mean size. Fragment size distribution was another useful parameter. Our results showed that fragment size distribution based on the number formed from the ring was a gamma distribution. Fragment size distribution based on the number formed from the whole drop was an exponential distribution. We also investigated fragment size distribution based on the volume formed from the whole drop, which was a Rosin-Rammler distribution.