近年來微機電系統技術(MEMS)迅速發展，並引發了微全分析系統(μ-TAS)的研究，此系統具有體積小、成本低、檢測只需少量樣本、反應時間快、便於攜帶等優點，為了整合更多的功能在有限的晶片面積上，不同平面的三維結構晶片才是未來的發展潮流。
本研究利用二維與三維十字型微管道進行液滴生成之研究，藉著改變兩工作流體在入口的流量比，可以控制液滴生成的速率及液滴的體積，並且在管道出口不唯一的情況下比較兩管道之實驗數據，試著找出三維管道是否有優於二維管道的地方，結果顯示在液滴生成的速率上，三維管道將遜於二維管道；接著進一步探討液滴形成的機制，發現在二維管道中使液滴斷裂的機制為壓阻力的影響，而三維管道中剪應力影響的機制較二維管道多；利用這些機制，配合改變毛細數(Ca)、QR值及管道深寬比(aspect ratio)，可在液滴生成的控制上進行更廣泛的研究。

Micro-Electro-Mechanical-System (MEMS) has developed rapidly in recent years, and it facilitates the study of micro total analysis system (μ-TAS). The system offers several potential advantages such as portability, low cost, small volume of samples and reagents, short reaction time, and easier to carry and so on. In order to integrate more functions in limited chip area, the three-dimensional structure chips in different plane are the future trend.
In this study, we use two-dimensional and three-dimensional cross microchannels to research the droplet formation. Through change flow rate of two working fluid at the entrances, we can control the rate of droplet formation and the droplet size; in the case of the channels exits are not unique, we compare the experiment data of two channels, and try to find out whether the three-dimensional channel is superior to two-dimensional channel. The results show that in aspect of droplet formation rate, three-dimensional channel is inferior to two-dimensional channel. Further, we approach the mechanism of droplet formation, and detect that: in two-dimensional channel the mechanism of droplet fracture is the effect of pressure resistance, and in three-dimensional channel the shear stress is more effective than in two-dimensional channel. Make use of these mechanism with changing capillary number, QR value and aspect ratio of the channels; we can do more extensive research in droplet formation control.

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