本文主要在設計新型的捕捉顆粒生物晶片，先透過COMSOL軟體進行計算流體力學的模擬，了解於此設計中會產生之速度流場以及顆粒的運動狀態。此生物晶片將蜻蜓翼與微流道結合在一起，利用蜻蜓翼在流動時會於翅膀皺摺凹陷處產生渦旋之特性，擬於微流道內產生低雷諾數渦旋，進行微顆粒之捕捉。 本文著重於仿蜻蜓翼生物晶片的設計與三維粒子流動模擬，希望得到較好的顆粒抓取效果。經重複嘗試，對於寬度200μm的微流道，蜻蜓翼連續壁弦長806μm，連續壁厚度61μm，入口流速0.52 m/s可產生明顯的蜻蜓翼渦流；入流口賦予50。的入流傾角，可增強微流道之起始渦度，有利顆粒捕捉(50顆約可捕捉2顆；捕捉率4%)，本文也嘗試階梯式兩只蜻蜓翼串接的流場模擬，適當橫向增胖蜻蜓翼尺寸一倍，捕獲率可達6%；對於未來進一步擴充為陣列式顆粒捕捉器具有應用參考價值。 This work presents the design of a new flow chip to capture particles. A dragonfly wing blocks along the centerline of a microchannel to generate multiple vortex in the corrugated grooves streamwisely. These multiple vortex in the dragonfly wing are used to capture more particles. Different from the conventional vortex-based flow chips with rectangular grooves along the both sides channel wall, the dragonfly wing grooves here in is designed to capture central -part particles novelly. The chord length of the dragonfly wing is 806 μm and thickness ratio is 7.5 %. Through the CFD simulation result (by COMSOL or FEMLAB), the inlet velocity of 0.52m/s can induce obvious vortex pattern in the corrugated dragonfly wing inserted in a microchannel of 200μm wide. The inclined angle of 50。at the channel entrance can provide enough initial vorticity strength beneficial to the particle capture rate of 4% per dragonfly wing structure. This work also tried two dragonfly structure cascadedly connected together. When the thickness ratio of the dragonfly wing double, the cascaded two-wing case can increase the capture ratio up to 6%. These simulation message reveals the usefulness of increasing the particle capture ratio of flow array design. It’s also good for the integration and application in tumor cell capture, sorting and separation in the future.
