一种非对称结构微流体混合器的设计与分析

Design and Analysis of an Asymmetric Structured Microfluidic Mixer

微流体混合器可以用于不同流体之间的混合与反应,其与化学传感器结合构成的化学分析测试系统,具有灵敏度高、响应时间短和稳定性好的特点。在微电子机械加工技术的基础上,设计了一种新型的、具有非对称分离重组结构的微流体混合器,并应用有限元方法建立了仿真模型,讨论了在不同雷诺数（Re=10~80）下,通道几何结构参数对微混合器内的流体流动特性和混合效率的影响。研究结果表明,微流体在该混合器内形成了扩展涡、分离涡和迪恩（Dean）涡,实现了涡系的叠加和强化,加大了流体间的扰动,增加了流体的接触面积,从而大大增强了混合效率。

Microfluidic mixer can be used for mixing and reaction between different fluids. The chemical analysis test system consisted of the microfluidic mixer and chemical sensor has the fea- tures of high sensitivity, short response time and a good stability. Based on the microelectronic mechanical technology, a novel microfluidic mixer with the asymmetric split and recombine structure was designed, and the simulate model was built using the finite element method. The effects for the geometry parameters of the micro-channel on the fluidic behavior and mixing index were discussed under different Reynolds numbers （Re = 10 - 80）. The study results indicate that the expansion vortex, separated vortex and Dean vortex are formed in the designed micromixer, the combination and enhancement of the vortex systems are achieved, the disturbance between fluids and the contact area of the fluids increase, then the mixing index significantly is enhanced.