Dynamics of Bubble Breakup in Improved AFRs with a Sharp Corner Structure

Abstract

The influence of the sharp corner structure of the advanced flow reactor (AFR) heart-shaped unit developed by Corning Inc. on bubble breakup dynamics was visually investigated. It was found that the height and angle of the sharp corner structure in the AFR could significantly affect bubble breakup behavior and change the flow regime range. Three flow patterns were observed: non-breakup, breakup with partial obstruction, and breakup with permanent obstruction, among which breakup with permanent obstruction is the primary flow pattern. Under experimental conditions, when the height and the angle of the sharp corner are 0.4 mm and 90°, the range of the bubble breakup flow pattern is the widest. The bubble breakup process of breakup with permanent obstruction could be divided into the squeezing stage, the transition stage, and the rapid pinch-off stage. Furthermore, a correlation for predicting the period of bubble breakup in the AFR with a sharp corner structure is proposed.