A new droplet breakup mechanism is previously proposed—interface-shrinkage-driven breakup. In coaxial microdevices, when the contact angle between the continuous phase and dispersed fluid channel (DFC) is sufficiently low, the new mechanism instead of the classic shear-driven mechanism dominates the breakup. The present study further investigated the new mechanism in microdevices with DFCs of different shape. Critical contact angles in different devices were determined by theoretical analysis and verified by experiments. It was found that the critical contact angle for the new mechanism depends on the shape of the DFC. The droplet size was measured for different devices when the new mechanism dominated the breakup. In contrast to the case for the shear-driven mechanism, the droplet size is little affected by the capillary number. Mathematical models were established to predict the droplet size in different devices and results were found to agree well with experimental results. © 2017 American Institute of Chemical Engineers AIChE J, 2017

中文翻译：

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界面收缩驱动的微器件中具有不同分散流体通道形状的液滴破碎

先前提出了一种新的液滴破碎机制-接口收缩驱动破碎。在同轴微设备中，当连续相与分散流体通道（DFC）之间的接触角足够低时，新机制代替了经典的剪切驱动机制占主导地位。本研究进一步研究了具有不同形状的DFC的微器件中的新机制。通过理论分析确定不同设备中的临界接触角，并通过实验进行验证。已经发现，新机构的临界接触角取决于DFC的形状。当新机制支配破碎时，对不同装置测量了液滴尺寸。与剪切驱动机构的情况相反，液滴大小受毛细管数量的影响很小。建立了数学模型来预测不同设备中液滴的大小，结果与实验结果吻合良好。©2017美国化学工程师学会AIChE的Ĵ，2017年