Gas-containing emulsion is a common form of multiphase fluid encountered in petrochemical transportation pipelines and multiphase reactors. Understanding the interfacial dynamics within such complex fluids is crucial for optimizing industrial processes. Although bubble detachment behavior within conventional single droplets has been widely probed, the detachment dynamics of a bubble inside a water-in-oil (W/O) droplet remain underexplored. In this paper, the detachment dynamics of a CO2 bubble within a static droplet dispersed in a W/O emulsion are quantitatively investigated using a custom-built visualization experimental platform. Experimental results indicate that the drainage time serves as a key factor for characterizing interfacial stability. Higher interfacial tension can inhibit the intensity of marginal regeneration, thereby significantly prolonging the drainage time. Furthermore, the drainage time is positively correlated with the bubble growth rate but negatively correlated with the droplet volume. Based on dimension analysis, an empirical model constructed with the modified Weber number (Weg) and Bond number (Bog) is proposed to predict bubble detachment time under various fluid and dynamic conditions. This work reveals the dynamic mechanisms of bubble rupture at confined liquid–liquid interfaces, providing an experimental basis and predictive tool for evaluating emulsion stability in industrial processes such as CO2 flooding.
Sun et al. (Sun,) studied this question.