Generating Gas‐Liquid‐Liquid Three‐Phase Microflows in a Cross‐Junction Microchannel Device

Abstract The generation of gas‐liquid‐liquid three‐phase microflows in a cross‐junction microchannel device is experimentally analyzed. Three gas‐phase and eight water‐phase flow manners at the cross junction are described with oil phase as continuous phase. Comparing with the gas‐liquid and liquid‐liquid two‐phase microflows, similar flow behaviors of dispersed phases exist in the three‐phase processes but new capillary numbers as well as the phase ratio of dispersed phases need to be introduced in the flow maps to distinguish the complicated three‐phase flow modes. Although the three‐phase flows are mercurial at the channel junction, only six flow patterns are observed in the downstream microchannel. According to the experimental results, the effects of bubble/droplet generation manners on their size distributions are indicated. The generation mechanisms of bubbles and droplets are analyzed and correlated equations are established for their average volumes.