隨著微機電系統(MEMS)體積小、成本低及反應時間快…等優勢陸續被人們所看見，因此更多人選擇在微小尺度的平台上做更多的研究，但隨著研究種類越來越多，也使得實驗的結構越來越複雜，因此雖然有如此多的優點，但還是需要有更多的儀器設備來互相輔助及配合。
在先前的研究中因為只能透過顯微鏡去觀測合成液滴在二維平面的混合狀態，因此本研究中使用數值模擬的方式觀測液滴在不同角度中的形成過程。本研究在數值模型選擇上主要選用VOF以及Species模型，其中VOF模型控制著液滴生成、Species模型控制著合成液滴內試劑與水的混合，使用以上設定模擬出三維十字交疊管內的液滴形成、液滴內試劑與水的混合，並將模擬數據與實驗數據做對比發現兩者液滴生成的尺寸數據在定性上是相同的，最後把「混合程度」做定量化以便我們探討不同尺寸的合成液滴在不同轉彎類型管道中其合成液滴內混合的優劣。

With micro-electromechanical system(MEMS) small size, low cost, fast response time and other advantages been seen, more and more people choose to do research on the micro-scale platform. However ,with the increasing variety of research ,the structure of the experiment is becoming more and more complex. Although there are so many advantages ,it is necessary to have more instruments and equipment to assist and cooperate with each other.
In the previous study, it was only possible to observe the mixed process of synthetic droplets in two-dimensional plane by microscope, in this study, numerical simulation is used to observe the mixing process of droplets by different perspective.
The VOF and Species models are mainly used in the selection of numerical models, the vof model controls the droplet generation, the species model controls the mixing of reagent and water in synthetic droplets, and use the above settings to simulate the formation of droplets in the three-dimensional cross microchannel and mixing of reagent and water in the droplet ,and we comparing the simulated data with the experimental data ,it is found that both droplet’s size data are qualitatively the same. In the end, we quantified the "mixing index" so that we can discuss different size droplet mixing in different type microchannels so we can tell which microchannel is much better.

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