本研究探討非牛頓流體在弧型流道中的混合現象，使用之非牛頓流體為含微量玫瑰紅螢光劑及不含玫瑰紅螢光劑之羧甲基纖維素水溶液，並使用冪次法則去描述非牛頓流體的剪應力和剪應變率的非線性關係；而弧形流道的形狀包括了弧形、S形及連續彎曲的流道。本研究利用數值模擬及實驗來探討流量、主流道截面深寬比、主流道彎曲之半徑及非牛頓水溶液之濃度對於混合效率的影響。其中，實驗過程包含：利用光微影技術製作母模、使用PDMS翻模，並將PDMS與載玻片接合成流道，再使用共軛焦顯微鏡取得流道內螢光溶液之流動及濃度分布的影像，及使用數值軟體CFD-ACE+模擬在微混合器中的三維流動及擴散現象，結果顯示數值模擬與實驗之結果相當一致，並得知在以下條件中微混合器有較佳的混合效率：(1)雷諾數越高；(2)非牛頓流體的濃度越高；(3)主流道截面深寬比越大；(4)主流道彎曲半徑越小。

Mixing of non-Newtonian fluids in curved channels is investigated in this work. The non-Newtonian fluids considered are the aqueous solutions of Carboxymethyl Cellulose Sodium with Rhodamine B and without Rhodamine B. The relation between shear stress and shear strain rate of the non-Newtonian fluids is modeled by a power law. The shapes of the curved channels include arcs, S-shaped channels and a combination of many S-shaped channel. The effects of the flow rate, the concentration of non-Newtonian fluid, and the aspect ratio and the curved radius of main channel on mixing efficiency are examined by numerical simulation and experiment. The fabrication process of the micromixers includes applying the photolithography method to fabricate SU-8 mold, replicating the mold by PDMS (polydimethysiloxane) and bonding the former with a sheet of cover glass. The fluid flow and mixing is observed by a confocal spectral microscope, Leica TCS SP2. Besides, we apply the commercial package, CFD-ACE+, to simulate the three-dimensional flow and mixing in the micromixer. Agreement of simulation and experiment results is found for the case considered. The results of this research show that the mixing efficiency can be improved by increasing the Reynolds numbers, the concentration of non-Newtonian fluids and the aspect ratio of the main channel section, and decreasing the curved radius of the main channel section.

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