本文提出結合渦流引發接頭及平面T形流道形成之微混合器，使流體在第一混合流道產生渦流，當流體到達T形接頭時，讓帶有渦流之流體匯入主流道，以促進流體混合。由於網格法的網格尺寸不夠小，在高培克萊特數下，會有數值擴散的影響，為解決此問題，本研究使用結合流體粒子反向追跡與擴散模式的解法與反向隨機漫步蒙地卡羅法來模擬流體的混合，所得結果顯示兩種模擬能互相驗證。本研究結果顯示，將T形流道入口處接上渦流引發接頭，流體進入主流道前已具渦流，會使渦流加速，當流體進入主流道後能夠增加橫向對流，以促進混合。當雷諾數為130至160，主流道橫截面發展出由兩側渦流結構帶動中央渦流，相較於三個渦流結構能有較好的混合效果。渦流引發接頭同側兩入口注入兩種不同流體，藉由兩流體在早期就增加流體接觸面積，使混合效率增加。最後，本微混合器能在較低的雷諾數下發生捲入流動。與平面T形微混合器相比當雷諾數為120至140，出口混合度相差超過20倍之多，但壓降才相差1.3倍；當雷諾數最高為160時，出口混合度相差了四倍左右，但壓降卻只多了1.4倍，所以此微混合器有較好的混合表現。

We propose a micromixer constructed by combining vortex-inducing junctions and a planar T-shaped microchannel. The eddies induced by vortex-inducing junctions in the confluent flow into main microchannel may enhance fluid mixing. To reduce numerical diffusion under high Peclet number, a particle tracking method with the diffusion model proposed by Matsunaga is applied to simulate fluid mixing. The results show that injecting two different fluids into both inlets of vortex-inducing junctions will enhance mixing by increasing the interfacial surface between the fluids in early time. Besides, this micromixer increases the area of the interfacial surface between the fluids effectively and causes engulfment flow at lower Reynolds number.

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