外加結構對微液滴內流體現象之探討

Influence of fluidic phenomena in droplets by additional structures

趙偉志(Wei-Chih Chao)

指導教授 ： 饒達仁

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2007年)

摘要

本文以介電濕潤(EWOD: electrowetting on dielectric)技術為基礎，設計並製作共平面式電極的數位微流體操控晶片，加入微粒於液滴內，藉由觀察液滴內微粒的位置變化，以統計方法分析外加結構對流體現象的影響。
首先假設液滴流體現象之流體可逆性與液滴來回移動的相關係數成正比，並假設外加圓柱結構會影響流體可逆性。為了驗證假設，本研究發展出一套運用機率統計、線性代數以量化、描述並分析液滴內微粒位置分布的方法，微粒位置分布(PPS: Particles position distribution)分析法。接著利用微粒位置分布分析法統計微粒位置變化的情形，將微粒位置機率分布做成轉換矩陣，以系統的架構去描述不同初始條件下，微粒位置分布的結果，並以相關係數量化、比較其結果並分析。最後以假設檢定驗證統計假設及微粒位置分布分析法。
本研究由實驗結果得知，液滴來回移動的微粒位置分布之相關係數與流體可逆性成正比。並利用統計方法發展出一套可量化分析微粒位置分布(PPS)的分析方法。從實驗結果與分析方法中得知，外加結構會使得液滴來回移動的微粒位置分布之相關係數下降，因此外加圓柱結構於介電濕潤晶片會降低液滴的流體可逆性。

關鍵字

介電濕潤 ； 微流體 ； 微粒 ； 液滴 ； 圓柱結構 ； 統計

並列摘要

This study reports that designing and fabricating digital micro-fluidic control system by using electro-wetting on dielectric actuations on coplanar electrodes with no cover plate, and joins particles in the droplet to observe particle position variation, which can be used to probe into “influence of fluidic phenomena in droplets by additional structures” by statistical method analysis.
First supposes the correlation coefficient that droplet back and forth moves, and the fluid reversibility have the direct ratio, and additional structures affect fluid reversibility. In order to confirm the supposition, this research develops one set method, Particles position distribution, uses probability statistics, linear algebra to describes and quantitative analyze position distribution of particles in the droplet. Uses the Particle position distribution analytic method statistics particle position variation in addition the situation, makes the particle position probability distribution the transformation matrix, describes under the different initial condition by the system overhead construction the particle position distribution result, and analysis result and it’s the correlation coefficient.
This research knew by the experimental result, the correlation coefficient that droplet back and forth moves, and the fluid reversibility have the direct ratio. And utilize statistical method to develop one set method to describes and quantitative analyze position distribution of particles in the droplet; learn from the experiment and analytical method, additional structure will reduce flow reversibly of droplet.

並列關鍵字

cylinder ； droplet ； electrowetting on dielectric(EWOD) ； microfluidics ； microparticle ； statistics

參考文獻

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