Abstract The breakup process of viscous droplets in Y-shaped microchannel was visually investigated. The dynamics of droplet breakup with partial obstruction was primarily studied due to its wide operating range and applicability. The rupture process of droplet could be divided into squeezing, transition and rapid pinch-off stages. In the squeezing stage, the minimum neck width displays a power-law relation with time, and the power-law index α decreases with increasing two-phase viscosity ratio λ. The effect of the capillary number of continuous phase Cac and the length of the mother droplet l0 on α is nearly negligible. In the transition stage, the minimum neck width varies linearly with time, and the slope increases with decreasing λ, increasing Cac and l0. In the rapid pinch-off stage, the minimum neck width declines exponentially with time, and the power-law index β decreases with increasing λ and decreasing l0, however, it is almost independent of Cac.

中文翻译：

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Y形微通道中粘性液滴的破碎动力学和机制

摘要 对粘性液滴在Y形微通道中的破碎过程进行了目视研究。由于其广泛的操作范围和适用性，主要研究了具有部分阻塞的液滴破碎动力学。液滴的破裂过程可分为挤压阶段、过渡阶段和快速夹断阶段。在挤压阶段，最小颈部宽度与时间呈幂律关系，幂律指数α随着两相粘度比λ的增加而减小。连续相 Cac 的毛细管数和母液滴长度 l0 对 α 的影响几乎可以忽略不计。在过渡阶段，最小颈宽随时间线性变化，斜率随着λ的减小、Cac和l0的增大而增大。在快速夹断阶段，最小颈部宽度随时间呈指数下降，