In this article, polyethylene oxide glycerin aqueous solution is used as the dispersed phase, and cyclohexane is used as the continuous phase to study the formation mechanism of viscoelastic fluid droplets in a step-emulsification microdevice. The formation process of viscoelastic droplets mainly includes three stages: two-dimensional expansion stage, necking stage, and pinch-off stage. The elasticity has basically no effect on the two-dimensional expansion stage, but it can delay the process of the necking stage and cause the beading phenomenon of droplets in the pinch-off stage. The results show that the effect of elasticity on the droplet size is weak, but it cannot be ignored. Moreover, the elasticity will be coupled with the viscous force to reduce the operating range of the dripping regime. Finally, the influence of the elasticity on the formation of satellite droplets is analyzed, and the method to prevent the influence of satellite droplets is proposed.

中文翻译：

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阶梯乳化微装置中粘弹性液滴的形成

本文以聚环氧丙烷水溶液为分散相，环己烷为连续相，研究了阶梯乳化微器件中粘弹性液滴的形成机理。粘弹性液滴的形成过程主要包括三个阶段：二维膨胀阶段、颈缩阶段和夹断阶段。弹性对二维膨胀阶段基本没有影响，但会延缓颈缩阶段的进程，造成夹断阶段的液滴成珠现象。结果表明，弹性对液滴大小的影响较弱，但不容忽视。此外，弹性将与粘性力相结合，以减小滴水状态的操作范围。最后，