基于混沌混合的分合式微混合器研究

摘要/Abstract

摘要： 按照混沌混合理论构建了Smale、Helical和Baker三种微混合器，为研究其混合机理与混合效果，对不同雷诺数下的对流扩散和混合进行了数值模拟，并用实验结果进行了验证。结果发现：实验结果与数值模拟结果吻合得很好。在低雷诺数下，由于Baker微混合器中流体的分层作用强，明显增大了流体的接触面积，也加快了流体混合速度，其混合效果要明显优于另外两种混合器;然而，在较大的雷诺数下，Smale微混合器中流体混合效果则优于Baker微混合器，其原因是Smale微混合器的分层效果虽然不如Baker微混合器，但其对流作用明显强于Baker微混合器;Helical微混合器因没有分层作用，其混合主要依赖于对流，所以在低雷诺数下混合性能较差，而高雷诺数下混合性能有所提高。

关键词: 分合式微混合器, 混沌对流, 扩散, 分层, 雷诺数

Abstract: Three trypes of micromixers, Smale, Helical and Baker micromixers, were built based on chaotic theory. In order to illustrate mixing mechanism and mixing effects, numerical simulations were carried out at various Reynolds numbers. Corresponding experiments were conducted to verify the numerical results. The results show the good agreements between numerical results and experimental results. Baker micromixers have more excellent mixing effects at low Reynolds numbers than that of Smale micromixers，because more-folds of interface areas between two streams caused by lamination expedite mixing. However, the mixing effects of Baker micromixers were not a patch on that of Smale at high Reynolds numbers. The reasons should be that, more convective mixings owing to more bending channels in Smale micromixers intensify mixing effects besides the lamination being slightly inferior to Baker micromixers. The mixing effects in Helical micromixers are not so satisfied because of no lamination at low Reynolds numbers, and somewhat improved at high Reynolds numbers.

Key words: splitting-merging micromixer, chaotic convection, diffusion, lamination, Reynolds number

中图分类号:

史冬冬;李金贝奇;王瑞金;朱泽飞. 基于混沌混合的分合式微混合器研究[J]. 中国机械工程.

SHI Dongdong;LI Jinbeiqi;WANG Ruijin;ZHU Zefei. Investigation on Splitting-merging Micromixers Based on Chaotic Mixing[J]. China Mechanical Engineering.

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