Step emulsification is a low-shear method to produce monodispersed microdroplets by spontaneous breakup of dispersed fluid at a spatial "step". As a semi-open microfluidic system, controllable coalescence of multiple components in step emulsification has not been achieved. Here, we use a low voltage to control the coalescence position of flow tips in the terrace. By investigating the interaction between the coalescence behavior and the hydrodynamics of the drop formation, we numerically predict the shape evolution of the flow tips and give a semi-empirical model to calculate the sizes of droplets by the flow rates and the voltage. Furthermore, we explore the capabilities of the electro-coalescer based on step emulsification. To trigger the coalescence in the wide reservoir, the clogging problem in precipitate-producing reactions is avoided. Besides, the low-shear nature of step emulsification also facilitates the production of multilayered droplets.

中文翻译：

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乳化过程中的电聚结法：动力学和应用。

逐步乳化是一种低剪切方法，通过在空间“步骤”处自发地分散分散的流体来生产单分散的微滴。作为半开放式微流体系统，尚未实现分步乳化中多种组分的可控合并。在这里，我们使用低电压来控制平台中流动尖端的合并位置。通过研究聚结行为与液滴形成的流体动力学之间的相互作用，我们在数值上预测了流动尖端的形状演变，并给出了一个半经验模型，以通过流速和电压来计算液滴的大小。此外，我们还基于逐步乳化技术探索了电动凝聚器的功能。要触发宽水库中的合并，避免了产生沉淀物的反应中的堵塞问题。此外，逐步乳化的低剪切性质也促进了多层液滴的产生。