本研究使用商業計算軟體(CFDRC)，來模擬去離子水和剪切稀化流體(羧甲基纖維素水溶液)在以下的微混合器中的流動與混合行為：具固定曲率半徑之蜿蜒流道，具步階式增減曲率半徑之蜿蜒流道及擁有漸縮漸擴截面積之蜿蜒流道。本研究探討在這些微混合器中，幾何尺寸對於流動與混合行為的影響。接著，比較去離子水與剪切稀化流體在等截面積之蜿蜒流道中流動的情形。最後，觀察較高流速下，剪切稀化流體於等截面積之蜿蜒流道內的狄恩不穩定性。從模擬的結果，可以得到以下的結論：(一)具漸縮漸擴寬度之蜿蜒流道會產生分離渦流，因此增進流體的混合。(二)剪切稀化流體在具漸縮漸擴截面之蜿蜒流道會有較小的表象黏滯係數。(三)由於狄恩不穩定性所生成之狄恩渦流會大幅地增進流體的混合。

In this work, we use commercial codes (CFDRC) to simulate the flow and mixing behaviors of DI water and shear-thinning fluids (aqueous solution of Carboxymethyl Cellulose) in the following micromixers：serpentine channel with constant curvature radius, serpentine channel with stepwise increasing and decreasing curvature radiuses and serpentine channel with converging-diverging cross section. We investigate the effect of geometry on the flow and mixing behaviors in these micromixers. We also compare the flow of DI water and shear-thinning fluids in serpentine channels with constant cross section area. Finally, we observe the Dean instability of the flow in serpentine channel with constant cross section for shear-thinning fluids with high velocity. From the simulation results, we have the following conclusions：(1) The converging-diverging width of serpentine channel causes separation vortex and so enhances fluid mixing. (2) Shear-thinning fluids in serpentine channels with converging-diverging section area shows a smaller average apparent viscosity. (3) The Dean vortexes due to instability considerably improves fluid mixing.

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