利用渾沌電滲流進行矩形微混合器的設計理念是透過調整微流道管壁內電極片的電壓來驅使相鄰電雙層內的流體流動，進而產生不同型態的全流體電滲流，然後透過兩種不同流動型態的週期性切換，來生成渾沌流，以提升矩形區域內微粒子的混合效率。
本論文以Lyapunov指數來量化流體流動的渾沌現象，Lyapunov指數正值是渾沌現象的必要條件，Lyapunov指數越大則流體的渾沌運動越強烈，也越快造成粒子混合。另外，矩形區域內渾沌流佔有的比例，是影響最終粒子混合效率的主要因素。
本論文分析混合度的方式是計算粒子占有混合器矩形面積的比率，稱為佔有率。使用一階時延模型來擬合不同時間的粒子佔有率，可輕易獲得混合器的最終佔有率以及佔有率的動態特性。接著計算混合器達到50%佔有率所需時間作為混合效率的量化值，混合器達到50%混合度所需時間越小，混合效率就越高。
混合器的最佳設計是通過改變混合器的長寬比、切換週期、側邊流速、邊界分離點，然後最小化各種組合的50%佔有率所需時間來實現。模擬研究指出，切換週期的增加對混合效率是有利的，但是週期太大反而會降低混合效率。長方型混合器會比正方型混合器需要更大切換週期來達到良好混合效率。側邊流速無益於正方型混合器，但少量的側邊流速可略微增加長方形混合器的混合效率。對於邊界分離點來說，分離點偏離中心點會造成非對稱的流動型態，這對混合效率有相當幫助。

In the design of rectangular micromixers using chaotic electroosmotic flow, the voltages of the electrodes in the microchannel wall are adjusted to drive the fluid flow within the adjacent electric double layer, thus producing electroosmotic bulk flow of various patterns. Through periodic switching between two different flow patterns, chaotic flow can be generated to improve the mixing efficiency of microparticles in a rectangular area.
In this thesis, the Lyapunov exponent is used to quantify the chaotic phenomenon of fluid flow. The positive value of the Lyapunov exponent is a necessary condition for chaotic phenomenon. The larger the Lyapunov exponent, the stronger the chaotic motion of the fluid and the faster the particles mixing. In addition, the proportion of chaotic flow in the rectangular area is the main factor that affects the final particle mixing efficiency.
In this thesis, the degree of mixing is analyzed by calculating the ratio of particles occupying the rectangular area of the mixer, known as the occupancy ratio. The final occupancy ratio and the dynamic characteristics of the occupancy ratio can be calculated by using a first order plus dead time model to fit the occupancy ratio over time. Next, calculate the time required for the mixer to reach 50% occupancy ratio as a quantitative measure of mixing efficiency. The shorter the time required for the mixer to reach 50% mixing degree, the higher the mixing efficiency.
The optimal mixer design is achieved by changing the aspect ratio, switching period, lateral flow rate, boundary separation point of the mixer, and then minimizing the time required for 50% occupancy ratio of various combinations. The simulation results show that the increase of the switching period is beneficial to the mixing efficiency, but when the switching period is too large, it will reduce the mixing efficiency. Rectangular mixers require longer switching periods than square mixers to achieve good mixing efficiency. The lateral flow rate is not good for the square mixer, but a small amount of the lateral flow rate can slightly increase the mixing efficiency of the rectangular mixer. For the boundary separation point, the deviation of the separation point from the center point will result in an asymmetric flow pattern, which is quite helpful for the mixing efficiency.

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