Numerical Simulation Study of bubble Breakup Mechanism in Microchannels with V-Shaped Obstacle

Microfluidic gas-liquid two-phase flow in microchannels plays a crucial role in diverse applications, from electronics cooling to biomedical engineering. Precisely controlling microbubble formation and breakup is essential for industrial microfluidic processes. This study investigates microbubble breakup in microchannels with V-shaped obstacles. Four breakup patterns are identified: no breakup, breakup with permanent gaps, breakup with partly obstruction, and breakup with permanent obstruction. The bubble breakup with permanent obstruction could maintain a wider flow pattern range. The bubble breakup process is categorized into three stages: squeezing, transition, and pinch-off. We observe power-law relationships between bubble characteristics and dimensionless time in each stage, and the impact of the capillary number Ca and liquid phase viscosity μL on bubble properties. This research deepens our understanding of gas-liquid two-phase flow in microchannels with obstacle structures and is relevant to analytical chemistry and fine chemical engineering applications.