本研究的混合器設計為一主動式混合器，將磁性人工纖毛 (artificial cilia)設置於T字形微流道內，運用磁場控制人工纖毛的運動軌跡，透過不同的運動軌跡使得流場產生擾動，增加流體分子間的擴散，以提升微流體裝置的混合效率。針對人工纖毛的運動軌跡與排列方式設計四種不同的T字形微流道。本研究為運用計算流體力學(computational fluid dynamic, CFD) 建立流固耦合模型 (Fluid-Structure-Interaction model, FSI model)，並結合奈威-斯托克方程式 (Navier–Stokes equations) 與質傳方程式求解流固耦合模型。利用模擬的方法進一步地探討實驗的結果，透過三維流場物理特性的分析，以了解影響混和效率的因素。
研究結果顯示運用磁性人工纖毛轉動不同的運動軌跡能有效地提升流場的混合效率，例如當人工纖毛擺動不對稱八字形運動軌跡時，相較於對稱八字形運動軌跡，其有較佳的混合效率(0.890)，且混合所需時間為4 s。進一步地探討八字形運動軌跡的延伸，故改變人工纖毛轉動的形式與速度比率，研究結果顯示當人工纖毛轉動速度比率為1:3的x方向八字形運動軌跡時為較佳的混合方法，且最終的混合效率為0.860，混合時間為3.6 s。而當微流道寬度增加至800 μm時，運用參數研究法 (parametric study) 分析人工纖毛V字形排列的夾角與距離，研究結果顯示當人工纖毛轉動頻率為30 Hz且人工纖毛V字形排列的距離縮短時，其環流量的絕對值為最大 (5.59 × 10-2 mm2/s)。故由模擬與實驗的結果顯示本研究設計的混合器能有效地提升微尺度流場的混合效率，且此混合器應用於微流體裝置的發展，例如藥物與試劑的混合。

Traditionally time-consuming and laborious bio-analytical techniques can be improved significantly through the realization of a microfluidic concept. In general, micromixing with high efficiency is advantageous in microfluidic applications. However, molecular diffusion with low efficiency during micromixing hinders the performance of the most previously reported micromixers. In this work, new designs of micromixers using artificial cilia agitation were proposed and demonstrated to provide a reliable alternative for micromixing. In addition, to shed light on the interaction between the artificial cilia and the surrounding flow, a computational fluid dynamic (CFD) method was also applied. Specifically, a fluid-structure interaction, or FSI method coupled the incompressible Navier–Stokes equations and the mass transfer equation were employed to quantify the flow fields induced by artificial cilia. Results show that the mixing performance reached the highest value of 0.890 within 15 seconds when an irregular figure-of-eight trajectory was followed by each artificial cilium. Moreover, a vortex was induced through the V-shaped distribution of artificial cilia in motion. The generated vortex is beneficial for enhancing micromixing efficiency. A new active flow mixing strategy was suggested in this thesis to efficiently transport/agitate flows by magnetically actuated artificial cilia for microfluidics and biomedical applications.

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