The step‐emulsification devices with parallel microchannels are promising for the high‐throughput formation of bubbles. However, the mechanism for bubble formation in such devices remains unclear. In present study, the mesoscale concept of compromise in a competition is used to reveal the mechanism. Nitrogen is used as the dispersed phase, and aqueous solutions with different viscosities are used as the continuous phase. The flow patterns and characteristic parameters for bubble formation are studied by using a high‐speed camera. The characteristic parameters include the head distance of gas–liquid interface and the neck width, and the size and formation frequency of bubbles. Bubble formation is affected by the hydrodynamic feedback in the chamber and the interfacial evolution process, characterized by the relative magnitude of the evolution velocity for the head distance and the neck width of gaseous thread in both microchannels. It is found that the compromise effect is beneficial for the formation of bubbles with excellent monodispersity.

中文翻译：

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中尺度对具有两个平行微通道的逐步乳化装置中气泡形成的影响

具有平行微通道的逐步乳化装置有望实现高通量气泡的形成。然而，在这种装置中形成气泡的机制仍不清楚。在本研究中，使用中尺度折衷的概念来揭示比赛的机理。氮气用作分散相，而粘度不同的水溶液用作连续相。使用高速相机研究了气泡形成的流动模式和特征参数。特征参数包括气液界面的头部距离和颈部宽度，以及气泡的大小和形成频率。气泡的形成受腔室中流体动力反馈和界面演化过程的影响，通过两个微通道中气态丝线的头部距离和颈部宽度的进化速度的相对大小来表征。发现折衷效果有利于形成具有优异的单分散性的气泡。