磁控四氧化三鐵微米線之高效化微混合器研究

Study of enhancing micromixing efficiency using magnetically controlled Fe3O4 microwires

黃科瑋(Ke-Wei Huang)

指導教授 ： 章明

中原大學/工學院/機械工程研究所/碩士(2014年)

https://doi.org/10.6840/cycu201400953

摘要

本研究重點在研擬以磁場控制磁性奈米材料運動之方式，提升微混合器之混合效益，具體作法係將混有Fe3O4奈米粒子之液體注入微流道中，以自製之磁場操控系統控制磁性奈米粒子團聚成微米線，再於流道中以轉動磁性材料方式不斷擾動，增加兩混合液體之接觸面積，即可達提升微混合器混合效益之目的。
　實際實驗時係以0.01wt%、0.03wt%、 0.05wt% 三種磁性流體濃度分別注入到寬度為100μm及 300μm之二組微流道中，透過比較0.8μl/min、2μl/min、4μl/min三種流速及50rpm、100rpm、200rpm三種磁場轉速等條件下近流道出口處之混合效益，以尋求最佳的磁控參數，實驗結果發現在磁流體0.05wt%重量百分濃度、100rpm的轉速及2μl/min流速等參數下，可得到極佳的混合效果。

關鍵字

微流體晶片 ； 混合器 ； 四氧化三鐵 ； 磁性操控

並列摘要

The research focus is to introduce magnetic microrods as active stirrers for enhancement of the mixing efficiency in microfluidic device. The Fe3O4 nanoparticles were added to the solution and controlled by a homogeneous rotating magnetic field. By aligning the magnetic particles along the field lines, the particles were transformed into rod-like structures, behaving similar to magnetic stir bars. The localized flow field generated by each rotating microrod perturbs the laminar flow in the microfluidic channel and mediates the mixing .
The experiment used three microrod concentrations 0.01wt%, 0.03wt%, 0.05wt% injected to micro-flow channels of widths 100μm and 300μm to compare the mixing efficiency with the microrods. Three different flow rates 0.8μl / min, 2μl / min, 4μl / min and microrod rotation speed 50rpm, 100rpm, 200rpm were also compared. The results reveal that 0.05wt% concentration of magnetic particles in the mixing solution and 100rpm angular speeds improves the mixing performance significantly.

並列關鍵字

micromixer ； microfluidic chips ； iron oxide ； magnetic manipulation.

參考文獻

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