Abstract As an important part of laboratory-on-a-chip (LOC) and micro-total analysis system (μTAS), micromixers are widely used in the fields of biological analysis and chemical synthesis. Most of them are used for the pretreatment of the detection and analysis system to realize the full mixing between the sample and the target to improve the accuracy of the inspection system. A new type of 3D-SAR micromixer with cross-channel structures was put forward after the systemic simulation by using CFD software. The mixing performance and mechanism of 3D-SAR micromixer with/without cross-mixing channel has been investigated with different Reynolds numbers (Re). The results show that the 3D-SAR micromixer with or without cross-mixing channel structures are of excellent mixing performance when the Re was high (Re > 50), and the mixing index is close to 1. While the concentration stratification of the two fluids in the cross-mixing channel (CMC) 3D-SAR micromixer is obviously better than that of no-cross-mixing channel (NCMC) 3D-SAR micromixer when Re is low (Re < 10). It is because the two fluids in the cross-mixing channel rotate counterclockwise at the mixing unit, which induces a vortex and increases the contact area between the two fluids. The mixing performance is greatly improved, and the mixing index at the outlet is more than 0.9. Meanwhile, in order to optimize the higher pressure drop of the CMC micromixer, a new 3D-SAR micromixer with the unbalanced-cross-mixing channel (UCMC) is proposed based on the CMC structure. This channel structure can meet the requirements of high mixing index and low-pressure drop at the same time, which is helpful to design and manufacture of new type micromixer.

中文翻译：

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一种具有高混频性能的交叉混频通道3D-SAR微混频器

摘要 作为片上实验室（LOC）和微量全分析系统（μTAS）的重要组成部分，微混合器广泛应用于生物分析和化学合成等领域。大部分用于检测分析系统的预处理，实现样品与目标物的充分混合，提高检测系统的精度。采用CFD软件进行系统仿真后，提出了一种新型跨通道结构的3D-SAR微混频器。研究了不同雷诺数 (Re) 下具有/不具有交叉混合通道的 3D-SAR 微混合器的混合性能和机制。结果表明，具有或不具有交叉混合通道结构的3D-SAR微混合器在Re较高（Re> 50）时具有优异的混合性能，且混合指数接近1。而交叉混合通道（CMC）3D-SAR微混合器中两种流体的浓度分层明显优于无交叉混合通道（NCMC）3D-SAR微混合器。 Re 低（Re < 10）。这是因为交叉混合通道中的两种流体在混合单元处逆时针旋转，产生涡流，增加了两种流体之间的接触面积。混炼性能大大提高，出口混炼指数大于0.9。同时，为了优化CMC微混合器的较高压降，提出了一种基于CMC结构的具有不平衡交叉混合通道（UCMC）的新型3D-SAR微混合器。这种通道结构可以同时满足高混合指数和低压降的要求，