數位微流體技術於產生奈升級液滴之數值模擬

Abstract

摘要

介電層電濕技術是不需要微流道便可控制流體的新技術，具有製程簡便、微量控制、混合容易、成本低廉等優點。本文模型的建立是基於流體力學中連續與動量方程式為依據，並把焦點放在液滴現象上。目的主要是模擬EWOD現象下的液滴傳輸、分離以及取樣(creating)奈升液珠等行為。本文中使用CFD-ACE+商業軟體將具體呈現奈升級液珠的模擬與實驗結果上的相互比對。最後為了抵抗流道高度變小時所帶來的流阻，則藉由設計主乘載電極中所鑲嵌鋸齒狀電極的開啟與關閉機制來提升液滴的壓差，並由最後的模擬結果得知增加鋸齒狀電極面積則能提升液滴壓差來抵抗流阻。

ABSTRACT

Electrowetting on dielectric (EWOD) is a new technology which moves fluid by surface tension effects and does not need channels to control fluids. It possesses some advantages, such as simplicity of fabrication, control of minute volume, fast mixing, low cost, and so on. This thesis presents a model based on a reduced form of the continuity and momentum equations to simulate the fluid dynamics of the droplets. This model is able to simulate transporting, cutting and creating of nano-liter droplets based on EWOD. In this study, the simulation results using commercial software, CFD-ACE+, for the motion of nano-liter droplets are reported and compared with the experimental results. In order to overcome the resistance of channels, a design of reservoir electrodes with a shape of jag is proposed to raise the pressure difference of the droplet between on-state and off-state of the electrode. The simulation results show that the pressure difference of the droplet increases as raising the area of the jagged electrode.