本文提出在T型微流道中加入矩形小翼對以促進流體混合，並使用田口法找出微混合器中較佳的幾何參數組合，選用的幾何參數包含矩形小翼對攻角、矩形小翼對高度、主流道中心與矩形小翼對開口中心處的距離及矩形小翼對之縱向間距。本研究使用數值模擬軟體CFDRC模擬微混合器中流體的混合現象，並配合實驗觀察在微混合器中實際的流動現象。製程上，以光微影技術製作微混合器母模，使用PDMS翻模並與載玻片接合完成微混合器之製作。最後使用雷射共軛焦顯微鏡觀察微混合器中流體的流動現象。本文結果顯示：(一) 矩形小翼的幾何參數對流體混合影響由大到小依序為:主流道中心與矩形小翼對開口中心處的距離 ，矩形小翼對攻角 ，矩形小翼對高度 ，矩形小翼對之縱向間距 ；(二) 在雷諾數足夠大時，流體流經具週期性排列之矩形小翼對產生的縱向渦流對與在各組矩形小翼對後的縱向渦流呈週期性變換位置，此兩種作用下，能有效且快速地促進混合；(三) 具矩形小翼對之微混合器相較於具擋板之微混合器有較好的混合效果；(四) 在高寬比1：3之流道中，以 0.167 、 22.5 o、 0.75 、 1.5 之矩形小翼對配置的混合效果最佳。

In this work, we propose the T-microchannel with rectangular winglet pairs ( RWP ) to enhance fluid mixing. The Taguchi method is applied to find out the better combination of the geometric parameters. The geometric parameters considered include the attack angle of RWP , the height of RWP , the distance between the center of the major channel and the center of the RWP , and the longitudinal interval of the RWP . We use the commercial codes, CFDRC, to simulate the fluid mixing in the micromixers. The SU-8 ( thick film photoresist ) is used to fabricate the mold of the micromixers by photolithography. Then we replicate the mold by PDMS ( polydimethysiloxane ) and bond the mold with a cover glass to complete the fabrication of a micromixer. Finally, the fluid flow in the micromixers is observed by a laser confocal spectral microscopy. The results show the following trends. (i) The effectiveness of the RWP geometric parameters is ranked as: > > > . (ii) When the Reynolds number is large enough, the fluids which flow through the RWP with periodic arrangement will generate the longitudinal vortex pair. And the longitudinal vortex pair will change their position periodically. Under these two effects, the fluids can be mixed effectively and rapidly. (iii) The mixing efficiency of the micromixers with RWP is better than that of micromixers with baffles built on the wall. (iv) When 0.167 , 22.5 o, 0.75 , and 1.5 , the mixing efficiency is the best for the channels with height to width ratio is 1/3.

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