本文提出一種使不同流體由兩入口注入具交錯T形截面之主流道的微混合器。首先，利用數值模擬軟體CFDRC模擬各流道段排列的混合情況，並找出其中有較佳混合效果的流道段排列方式，為了方便，我們使用代號A、B及C分別表示偏右的T形截面流道段、偏左的T形截面流道段及方形截面流道段。接著，利用田口法找出較佳的第一T形截面流道段長度(la)、第二T形截面流道段長度(lb)、方形截面流道段長度(lc)及流道內的模組排列方式，並分析各參數在Re = 0.01~10對混合的影響。為了驗證數值模擬是否可靠，使用微影技術製作微混合器，並利用雷射共軛焦顯微鏡擷取流體在微混合器中的混合影像，由模擬與實驗結果相比較，發現兩者相當一致。本文結果顯示：(一)流體在低雷諾數(Re ≤ 10)下依序流經偏右與偏左T形截面流道段後，會產生縱向渦流，且此渦流在接下來的方形截面流道段會持續存在並增進混合效果。(二)參數對混合度的影響由大到小依序排列為：流道內截面排列方式，第二T形截面流道段長度，方形截面流道段長度，第一T形截面流道段長度。(三)改變方形截面流道段長度與流道內的截面排列方式，幾乎不會影響壓降大小，而改變第一T形截面流道段長度與第二T形截面流道段長度，雖會影響壓降大小，但影響不大。(四)在低雷諾數(Re ≤ 10)時，具交錯T形截面之微混合器的參數以la = 0.75Wm、lb = Wm、lc = 0.75Wm (Wm代表主流道的寬度)及12個模組中皆為ABC的排列順序時的混合效果為最佳。

We propose a micromixer which allows two different fluids to flow into the main channel consisting of modular subsections with staggered T-shaped cross-sections. The simulation results obtained by the software, CFDRC, show the following trend. When mixing fluid flows into a T-shaped cross-section subsection with center moved to the right (represented by symbol A) and a following T-shaped cross-section subsection with center moved to the left (represented by symbol B), a longitudinal vortex is induced. The vortex persists in the following square cross-section subsection (represented by symbol C) and enhances mixing for the case with a small Reynolds number (≤ 10). Next, we fabricate the micromixer by photolithography and apply a confocal microscopy to acquire the mixing flow images. The comparisons of the simulation results and the images show qualitative agreement. Finally, we adopt the Taguchi method to select better parameters, including the length of the first and the second T-shaped cross-section subsection (la and lb), that of the square cross-section subsection (lc) and the arrangement of modules. The simulation based on the Taguchi method shows that the effectiveness of the parameters is ranked as: the arrangement of modules > lb > lc > la and the mixing efficiency of the micromixer with la = 0.75Wm, lb = Wm, lc = 0.75Wm (with Wm denoting the main channel width) and the staggered cross-sections of each of the twelve modules arranged in the order of A, B and C is higher than that of the other similar micromixers.

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