Droplet generation in microfluidic devices has emerged as a promising approach for the design of highly controllable processes in the chemical and pharmaceutical industry. However, droplet generation is still not fully understood due to the complexity of the underlying physics. In this work, micro‐computed tomography is applied to investigate droplet formation in a circular channel in a co‐flow configuration at different flow conditions (Ca < 0.001). The application of an in‐house developed scanning protocol assisted by comprehensive image processing allows for the time‐resolved investigation of droplet formation. By tracking different droplet parameters (length, radii, volume, surface, Laplace pressure) the effect of flow conditions on droplet progression is determined. As characteristic for the squeezing regime, final droplet size was nearly independent of Ca for higher Ca tested. For lower Ca, the final droplet size increased with decreasing Ca, which points to the leaking regime that was recently introduced in the literature.

中文翻译：

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微型计算机断层摄影技术用于3D时间分辨研究并流装置中单分散液滴的产生

微流控设备中液滴的产生已成为化学和制药行业中高度可控过程设计的一种有前途的方法。然而，由于底层物理的复杂性，液滴的产生仍未被完全理解。在这项工作中，应用微计算机断层扫描技术研究了在不同流动条件下（Ca <0.001）并流配置的圆形通道中液滴的形成。内部开发的扫描协议的应用加上全面的图像处理，可以对液滴的形成进行时间分辨的研究。通过跟踪不同的液滴参数（长度，半径，体积，表面，拉普拉斯压力），确定流动条件对液滴进程的影响。作为紧缩制度的特征，对于测试的较高的Ca，最终的液滴尺寸几乎与Ca无关。对于较低的Ca，最终的液滴尺寸会随着Ca的减少而增加，这表明了文献中最近引入的泄漏机制。