We present a scalable droplet generator with capillaries embedded in a microchannel, assembled with 3D printed T-connector and fittings. We first analyze the influences of geometric and operating parameters on droplet characteristics using a high-speed camera in a single-capillary device. We then scale up the device by parallel arranging three capillaries with axial misalignment to mitigate the interaction between droplets, which addresses the limitations of droplet productivity. We classify the droplets formed in the three-capillary device into different size distribution intervals and elucidate the underlying mechanism, enabling the manipulation of high-frequency generation of tiny droplets. At a velocity ratio of 12.0, the droplet generation frequency reaches 1260 Hz, in which the ∼30 μm droplets account for a large proportion of 65 %. Our low-cost and fast-fabricated capillary embedded devices have a high potential for producing high-throughput tiny droplets and handling liquid-liquid reactions requiring precise control of droplet size.

中文翻译：

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使用具有轴向错位的平行排列毛细管的可扩展液滴发生器设计


我们提出了一种可扩展的液滴发生器，其毛细管嵌入微通道中，并由 3D 打印的 T 形连接器和配件组装而成。我们首先使用单毛细管装置中的高速摄像机分析几何和操作参数对液滴特性的影响。然后，我们通过平行排列三个轴向错位的毛细管来扩大设备规模，以减轻液滴之间的相互作用，从而解决液滴生产率的限制。我们将三毛细管装置中形成的液滴分类为不同尺寸的分布区间，并阐明了潜在的机制，从而能够操纵微小液滴的高频生成。当速度比为12.0时，液滴生成频率达到1260 Hz，其中~30 μm液滴所占比例较大，达到65%。我们的低成本且快速制造的毛细管嵌入式设备具有很高的潜力，可用于生产高通量微小液滴和处理需要精确控制液滴尺寸的液-液反应。