被動式微流體混合裝置之設計與性能分析

Abstract

本論文針對微流體混合之物理現象進行研究，利用微機電系統製程技術製作出構造簡單並能增進微流體混合效率之被動式微混合器，此混合器利用立體彎管之結構使流體在低雷諾數時產生混沌移流現象。渾沌移流的發生通常表示流體界面快速的扭曲和拉長，這將可增加流體的接觸面積及減少擴散距離，而使兩液體快速的產生混合。在實驗過程中，我們改變微流道的幾何尺寸與配置以期了解各項參數的影響。結果顯示，流體的雷諾數、粘滯係數、流道深寬比及ㄈ型流道的個數皆會影響混合效果，從而選擇出被動式微流體混合裝置之最佳設計參數，以提供最適當的操作條件。

This thesis is proposed in order to investigate the physical phenomenon of fluids mixing in a passive micro-mixer. In experiment, MEMS fabricated passive micro-mixer with three-dimensional serpentine micro-channel is considered, which leads to chaotic advection at low Reynolds number and also enhance fluids mixing. The occurrence of chaotic advection typically indicates rapid distortion and elongation of fluid interfaces. It then significantly increases the area across which diffusion occurs, which leads to rapid mixing between fluids. The study examines the effects on the mixing of various parameters such as the geometrical layout and channel’s geometrical parameters. Result show that the Reynolds number, viscosity of fluids, the aspect ratio of channels and the numbers of “C-shaped” channels can affect the mixing effect. The analysis would be helpful for an optimal design of a passive micro-mixer.