Abstract
The bubble formation in a square microchannel with a converging shape mixing junction has been investigated under gas–liquid Taylor flow using a high-speed camera. A typical bubble formation process was found to consist of two steps including the expansion and rupture steps. The bubble length could be approximated as the product of the rupture time and two-phase mixture velocity. Significant influence of liquid viscosity and two-phase mixture velocity on the bubble length was observed, although a linear dependence of the bubble length on gas–liquid flow ratio is present for a given two-phase mixture velocity or liquid viscosity. This indicates that shear stress plays an important role in determining the bubble length in the current microfluidic device even at low Capillary numbers where the squeezing regime is expected to predominate. An empirical correlation expressing the bubble length as a function of gas–liquid flow ratio, liquid viscosity and two-phase mixture velocity was developed to describe the experimental results. The bubble frequency was found to reach a maximum as gas–liquid flow ratio is increased from 0.5 to 1. The cross-sectional shape of Taylor bubble was close to be square at low capillary numbers, which is in agreement with the literature results.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
