摘要
为提高低雷诺数层流条件下被动式微混合器的效率,依据"三维马蹄变换"数学模型,对流体进行"挤压拉伸""弯曲折叠""二次折叠"和"逆变换-交集"操作,得到了一款包含6个混合单元,总长度为15 mm的混沌流微混合器。仿真研究表明:在"低流速-扩散主导"阶段u=2×10^(-4)m/s时,t=300 s后混合器进入稳定混合状态,出口处的混合指数α_(Outlet)=97.82%;在"中流速-湍流发展"阶段u=5×10^(-3)m/s时,t=70 s后进入稳定混合状态,经3个混合单元后混合指数α_(Inlet4)=98.89%;在"高流速-湍流主导"阶段u=8×10^(-2)m/s时,t=22 s后进入稳定混合状态,经2个混合单元后混合指数α_(Inlet3)=99.35%。采用基于面投影微立体光刻的3D打印技术整体制备了混合器芯片,借助显微镜用可视化方法对不同进样流速下的混合器性能进行了验证,示踪剂颜色变化实验结果与表面浓度云图的仿真结果一致。
In order to improve the efficiency of passive micromixers under laminar flows at low Reynolds numbers,this study conducts a series of operations on fluids including"extrusion stretching,""curved folding,""secondary folding,"and"inverse transformation intersection"based on a mathematical model of 3Dhorseshoe transformation.The considered chaotic flow micromixer contains six mixing units with a total length of 15 mm.Simulations show that in the low flow rate-diffusion dominated stage,the mixer enters a stable state after t=300 s when u=2×10^(-4)m/s,and the mixing indexα_(Outlet)=97.82%at the mixer outlet.In the medium velocity-turbulence development stage,the mixer enters a stable state after t=70 s when u=5×10^(-3)m/s,and the mixing indexα_(Inlet4)=98.89%at the inlet of mixing unit 4.In the high velocity-turbulence dominated stage,the mixer enters a stable state after t=22 s when u=8×10^(-2)m/s,and the mixing indexα_(Inlet3)=99.35%at the inlet of mixing unit 3.The entire mixer chip is fabricated as a whole by3D printing technology based on surface projection micro-stereo lithography.The performance of the mixer at different injection flow rates is verified by visualization using a microscope.The results of the tracer color change experiment are consistent with the simulation results of the mixer surface concentration cloud map.
作者
张贺
杨爽
揣荣岩
李新
ZHANG He;YANG Shuang;CHUAI Rongyan;LI Xin(College of Information Science and Engineering,Shenyang University of Technology,Shenyang 110870,China)
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2022年第3期286-295,共10页
Optics and Precision Engineering
基金
辽宁省教育厅基础研究基金资助项目(No.LJGD2020014)。
关键词
微流体
混沌混合器
三维马蹄变换
3D打印
一体化制备
microfluidic
chaotic mixer
three-dimensional horseshoe transform
3D printing
integration preparation
