本文探討具有非對齊入口流道與分合流道模組接頭的微混合器，流體由非對齊入口進入主混合流道時形成渦流流動結構，而分合流道部分採用模組化設計，分合流道先分成兩個轉彎的流道，利用轉彎產生離心力，使流體產生拉伸折疊效應促進混合，再以非對齊T形接頭進行合流，期望多個分合流道模組情況下，使混合度大於0.9。本研究分合流道模組分別採用直角轉彎分合流道模組與非直角轉彎分合流道模組。影響後者的幾何參數甚多，我們利用田口法找出考慮之幾何參數的最佳組合，考慮之幾合參數包括分支流道分流角度、分支流道中匯流部份之外的分支流道中心線在轉彎前之長度、分支流道截面寬度、匯流部分的分支流道長度，並分析各雷諾數下的混合表現。本文考慮的對流擴散過程包括高培克萊特數的情形，若以網格法模擬會發生數值擴散，因此，本研究使用流體粒子反向追跡結合近似擴散模式進行數值模擬。為了驗證數值模擬的可信度，使用微影技術進行微混合器製作，在利用共軛焦顯微鏡觀察流體在流道中的混合狀況，並與數值模擬相互比較，發現兩者結果相當一致。本文研究的結果顯示，採用本文提出的非直角轉彎分合流道模組會有較低的壓降與更好的混合效率，且隨雷諾數增加，對流效應愈明顯，渦流強度及影響範圍增大，混合表現愈好。多模組設計中，隨分合流道模組數目增加，混合程度增加幅度會變小，且壓降會呈線性上升，在分合流道模組數為4時，採用具有非對齊入口流道與非直角轉彎分合流道模組的微混合器，當雷諾數為100時，其壓降仍在合理範圍內，而流道出口混合度可達到0.9以上。

This study investigates micromixers with non-aligned inlets and split-and-recombination module junctions. The incoming fluid streams from non-aligned inlets flowing into the main mixing channel result in a swirl flow. Then, the main mixing channel and a series of spilt-and-recombination modules are connected to form the micromixer. When fluid streams go through bends, centrifugal force will be developed. Centrifugal force can stretch and distort the interface between different fluids. Similarly, the recombination of fluid streams at non-aligned junction induces swirl flow. Both centrifugal force and swirl flow enhance the mixing performance. In this study, the split-and-recombination modules adopt sub-channels with either right angle bends or non-right angle bends. The simulation results of the grid method have numerical diffusion under high Peclet number. Thus, the particle tracking method with an approximation diffusion model is applied to the present cases. We use the Taguchi method to select better geometric parameters for the modules with non-right angle bends. Finally, we fabricate the micromixer by micro-lithography process and use a confocal microscopy to acquire the image for the mixing and flow in the micromixer. Comparisons of the simulation results and the experiment acquire images shows qualitative agreement. The results of this study show that the micromixers which adopt sub-channels with non-right angle bends have lower pressure drop and better mixing performance. The degree of mixing reaches a value larger than 0.9 for a micromixer adopting four modules with non-right angle bends at Reynolds number equal to 100.

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