This article aimed to study the characteristics of chaotic advection and mass transfer of viscous liquid–liquid flows in a novel 3D serpentine microchannel (TSM) with hybrid structures. The TSM and its corresponding experimental setup are established, and the CFD model is verified through flow field visualization experiments. Results reveal that efficient chaotic convection in TSM is achieved through continuous irregular spatial fluid deformation. The Lyapunov exponents greater than zero indicate the existence of chaotic behavior, and the maximum lineal stretch rate λ_M increases linearly with the characteristic Reynolds number. The mass transfer characteristics are evaluated by diffusion mass transfer number Φ and mass transfer field synergy number Fc quantitatively. The mixing index MI shows an increasing trend as Fc increases, while the mixing effectiveness ME decreases as the outlet Reynolds number Re_O decreases. The relationships of MI with λ_M and Fc and the relationship of ME with Re_O are established.

中文翻译：

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新型三维蛇纹微通道中粘性液-液流的混沌平流和传质


本文旨在研究具有混合结构的新型三维蛇形微通道 （TSM） 中粘性液-液流的混沌平流和传质特性。建立了 TSM 及其相应的实验装置，并通过流场可视化实验验证了 CFD 模型。结果表明，TSM 中的高效无序对流是通过连续的不规则空间流体变形实现的。大于零的 Lyapunov 指数表示存在混沌行为，最大线性拉伸速率 λ_M 随特征雷诺数线性增加。通过扩散传质数 Φ 和传质场协同数 Fc 定量评价传质特性。混合指数 MI 随着 Fc 的增加呈增加趋势，而混合效率 ME 随着出口雷诺数 Re_O 的减小而降低。建立了 MI 与 λ_M 和 Fc 的关系以及 ME 与 Re_O 的关系。