Microfluidic technology has gradually become one of the most promising and convenient methods to generate monodisperse droplets, but even so, stable preparation in a microfluidic device is still technically challenging. This paper developed a simple coaxial microfluidic device, only composed of commercial parts, which can readily be assembled, adjusted and cleaned. Based on this design, the effects of two phase flow on droplet diameter and flow pattern were investigated experimentally. Furthermore, a theoretical relation for stable generation of monodisperse droplets was established and proved to be reasonable by experiments. This relation divided stable region for preparing desired droplets, which would greatly improve the efficiency and controllability of stable preparation process in microfluidic devices. It could also provide a technique support for the standardization and commercialization of microfluidic devices in the future.

中文翻译：

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便捷的即插即用同轴微流体装置和单分散液滴产生的定量预测

微流体技术已逐渐成为产生单分散液滴的最有前途和便捷的方法之一，但是即使如此，在微流体设备中稳定制备仍然在技术上具有挑战性。本文开发了一种简单的同轴微流体装置，仅由商业零件组成，可以很容易地组装，调整和清洁。基于此设计，实验研究了两相流对液滴直径和流型的影响。此外，建立了稳定产生单分散液滴的理论关系，并通过实验证明是合理的。该关系划分了用于制备所需液滴的稳定区域，这将大大提高微流体装置中稳定制备过程的效率和可控性。