中文摘要：

设计了一种基于多重涡流的新型微混合器结构。该结构中多个呈反向分布的规则排列的扩张和收缩结构可产生迪恩流与扩张涡流,基于此,可进行高效率的被动式混合。首先阐述了该结构产生内部迪恩流和扩张涡流的机理,并利用COMSOL软件对该结构进行了液流混合过程的三维数值模拟验证,分析了不同流体流速对多重涡流强弱和混合程度的影响。最后制作了该微混合器,利用2种不同的染料进行了混合实验,通过分析样品的混合效果验证了该混合器的性能。仿真和实验结果均表明：该混合器在低输入流速（0.01μL/s）和高输入流速（7μL/s）下均可实现高效快速的混合,在0.8 cm的距离内即可实现完全混合,在输入流速为5μL/s时最高混合效率可达98.6%。

英文摘要：

Design a novel mixing structure consisting of several oppositely distributed expansion and contraction sections,which can generate Dean flow and expansion vortex.Based on this,the micromixer structure can realize high-efficiency mixing.The mechanism of forming Dean flow and expansion vortex are described first,then 3D numerical simulation is carried out to verify liquid flow mixing process by COMSOL,analyze effect of different flow rates on strong or weak of the multivortex and mixing degree.Finally,the micromixer is fabricated.Two different dyes are used for mixing experiment.Both the simulation and experimental results show that the mixer can obtain high efficient and fast mixing at the low rate of 0.01 μL/s as well as high input flow rate of 7 μL/s,the highest mixing efficiency is up to 98.6 % at the flow rate of input 5 μL/s.