چكيده به لاتين
Understanding of the interaction between oil droplets and gas bubbles and their coalescence, can lead to improvement in efficiency of many industrial, environmental and biological processes. Despite of extensive efforts carried out in this field, the study of this phenomenon has been done with many simplifications, (because of physical complexity and technological challenges), and less surveys had directly addressed the phenomenon itself. At the moment this issue is an open and ongoing topic, with so many challenges in it.
In the present study, in order to understand more about the bubble-droplet coalescence, a special experimental setup was completed and used. The main purpose of this study was to identify the phenomenon affecting the coalescence. Therefore after completing the setup, some dynamic and quasi-static tests were performed to observe the effect of mechanical parameters such as size and collision velocity on the drainage time of the film. The results showed that in addition to the spreading coefficient, some parameters such as kinetic energy and contact time, greately affect the collision result. It was observed that the size of particles in the studied interval wouldnt have much effect on the coalescence, and also realized that by adding salt to water, the drainage time decreases. The result showed that the drainage time and corresponding standard deviations were more than the coating time and its standard deviation. Finally, in this study, an equation for determining the initial distance of hydrodynamic interactions at the beginnig of it was achieved by linear fitting on aqquired data.
