复合侧壁微结构增强被动微混合的数值模拟研究  

Numerical Simulation on the Passive Micromixer With Composite Lateral Microstructure

作　　者：陈锦岚 牛东 蒋维涛[1,2] 刘红忠 CHEN Jinlan;NIU Dong;JIANG Weitao;LIU Hongzhong(State Key Laboratory for Manufacturing System Engineering,Xi'an Jiaotong University,Xi'an 710049,China;School of Mechanical Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学机械制造系统工程国家重点实验室,西安710049 [2]西安交通大学机械工程学院,西安710049

出　　处：《工程热物理学报》2022年第9期2382-2388,共7页Journal of Engineering Thermophysics

基　　金：国家杰出青年科学基金资助项目(No.51625504);中国博士后创新人才支持计划(No.BX20190272);西安市青年托举人才支持计划(No.095920201305)。

摘　　要：受到微结构对局部流场的调控作用的启发,建立了具有复合侧壁微结构的T型被动式微混合器,通过COMSOL数值模拟,分析了具有复合侧壁微结构的被动式微混合器的流场特性与混合效率,研究其在低雷诺数下的分子扩散作用及较高雷诺数下的二次涡旋效应。研究结果表明,对于分子扩散作用,复合微结构使得微通道内流通宽度减小,混合效果较好;对于二次涡旋效应,复合微结构使得微通道内二次涡旋的数量增加,能够有效提升混合效果。基于上述数值分析结果,在0.01≤Re≤50的工况下,采用复合侧壁微结构及最优的几何参数使得微混合器的混合指数达到了85%以上,与内置阻块型微混合器相比,内置复合侧壁微结构型微混合器具有较好的混合效果及较小的压降。Inspired by the microstructure on manipulation of the local flow field, T-type passive micromixer with composite lateral microstructures were established firstly. Then the flow field characteristics and mixing efficiency of the passive micromixer with composite lateral microstructure are analyzed through COMSOL numerical simulation, and the molecular diffusion under low Reynolds number and the secondary vortex effect under higher Reynolds number are studied. The results show that for molecular diffusion, the composite microstructure reduces the flow width in the microchannel, and the mixing effect is better;for the secondary vortex effect, the composite microstructure increases the number of secondary vortices in the microchannel, which can be effectively improve the mixing effect. Based on the above-mentioned numerical analysis results, in the working condition of 0.01 ≤ Re ≤ 50, the composite lateral microstructure and the optimal geometric parameters make the mixing index of the micromixer reach more than 85%. Compared with the built-in block type micromixers, the built-in composite lateral microstructure type micromixer has better mixing effect and smaller pressure drop.

关 键 词：被动式微混合器 侧壁微结构 分子扩散 二次涡流 数值模拟 

分 类 号：TQ027.1[化学工程]