Microbubble movement during its formation in a co-flowing liquid in a microfluidic chip

Abstract

Microbubble formation surrounded by a co-flowing lqiud (CFL) in a new-designed microfluidic chip was investigated in the present study. The movement of microbubble and the effect of CFL and nitrogen pressure on it during its formation were mainly focused. A new microfluidic chip was fabricated to realize the co-axial flowing condition of liquid. Experimental works were conducted based on the professionally-constucted high-speed microscopic camera system (HSMCS). Two concerned parameters which represent the movement of target microbubble were introduced. Experimental data and analysis results indicated that microbubble moves along the formation direction as time with a quadratic law. Futhermore, both nitrogen presussure and CFL contribute to the formation process drastically but from different aspects. The present study provided empirical references for studies in the movement of microbubble during its formation in CFL which contributes to realize the accurate controllability in diameter and size distribution of microbubbles.