SOR微型混合器的设计及实验研究

Design and experimental study of staggered oriented ridges micromixers

为实现微尺度条件下流体的均匀混合,按层流混合原理设计了一种三维结构的新型静态微型混合器.通过在微通道内设置周期交叉排列的导流块,在轴向的压力梯度作用下产生横向的流动,从而在微管道内产生对流体的搅拌作用,达到促进混合的目的.运用计算流体动力学方法分析了静态微型混合器内速度场的分布规律,阐述了发生混合的机理.采用罗丹明染料与去离子水的混合试验检测该微型混合器的混合性能,同时分析了微型混合器的混合效果与结构参数、雷诺数的关系.混合试验表明,交叉导流式Ⅱ型(SOR-Ⅱ)微混合器在低雷诺数和高雷诺数条件下都可以获得好的混合效果,而交叉导流式Ⅰ型(SOR-Ⅰ)微混合器只能在高雷诺数条件下获得好的混合效果.

To enhance fluid mixing in microfluidic system, a novel three-dimensional static micromixer was designed based on laminar flow mixing principle. With the staggered oriented ridges arranged periodically in the microchannel, the transverse components of flow were generated under a steady axial pressure gradient to stir the fluid and effectively enhance mixing in the microchannel. The distribution of velocity field in the static micromixers was investigated with the computational fluid dynamics method, and the mixing principle in the micromixer was analyzed. The performances of micromixers were measured through Rhodamine dye and deionized water mixing experiment, and the relationships of the mixing degree with the structural parameters and the Reynolds number were quantitatively investigated. Experimental results show that the staggered oriented ridges Ⅱ （SOR- Ⅱ ） micromixer can achieve good mixing in low and high Reynolds number, while the staggered oriented ridges Ⅰ （SOR-Ⅰ ） micromixer can achieve good mixing only in high Reynolds number.