同轴微通道中双乳液滴生成的数值模拟研究
Numerical Simulation Study on the Generation of Dual Emulsion Droplets in Coaxial Microchannels
摘要: 本文基于COMSOL Multiphysics 6.2与水平集(Level Set)法追踪油‑水‑油界面演化过程，构建了二维轴对称同轴微通道模型，探究聚焦孔直径与出口流道宽度之比(wn)、颈长(L3)和开角(θ3)对双乳液滴生成的影响。结果表明：该模型中双乳液滴存在滴流与射流两种生成模式，滴流模式下界面张力主导、单分散性好；射流模式下粘性剪切强、生成频率高。几何参数分析表明：增大wn可减小外液滴体积、增加生成频率，过大易导致液滴合并；增加L3主要延长射流长度，对液滴体积影响较小；减小θ3可提升剪切力，减小外液滴体积、增加生成频率，内液滴体积变化不明显。综上，几何参数可有效调控双乳液滴尺寸、频率等，为微流控双乳液滴在药物载体、功能胶囊等领域的应用提供了数值依据和设计参考。
Abstract: This study used COMSOL Multiphysics 6.2 and the Level Set method to track the evolution process of oil-water-oil interfaces. A two-dimensional axisymmetric coaxial microchannel model was constructed to investigate the effects of the ratio of the diameter of the focusing hole to the width of the outlet channel (wn), the neck length (L3), and the opening angle (θ3) on the generation of double emulsion droplets. The results show that in this model, there are two generation modes for double emulsion droplets: droplet flow and jet flow. In the droplet flow mode, the interfacial tension dominates and the monodispersity is good; in the jet flow mode, the viscous shear is strong and the generation frequency is high. Geometric analysis shows that raising wn reduces outer droplet volume and increases generation frequency; an excessively large wn is prone to cause droplet merging; increasing L3 mainly extends the jet length, with a relatively small impact on the droplet volume; reducing θ3 can enhance the shear force, reduce the volume of the outer droplet, increase the generation frequency, and the volume change of the inner droplet is not significant. In summary, the geometric parameters can effectively control the size and frequency of double emulsion droplets, providing numerical basis and design references for the application of microfluidic double emulsion droplets in drug carriers, functional capsules, etc.
文章引用：李梓乐, 张一梅. 同轴微通道中双乳液滴生成的数值模拟研究[J]. 化学工程与技术, 2026, 16(2): 113-125. https://doi.org/10.12677/hjcet.2026.162012

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