王安邦臺灣大學：應用力學研究所高智柏Kao, Chih-PoChih-PoKao2007-11-292018-06-292007-11-292018-06-292005http://ntur.lib.ntu.edu.tw//handle/246246/62574液滴蒸發乃是一種非常基本的自然現象，因為它在許多工業或科學研究有其重要性，例如：消防滅火、機具散熱等；除此之外，液滴蒸發也在噴霧乾燥、化妝品工業、噴墨列印等領域中佔有一席之地。在許多實驗程序中，粒子殘留的分佈情形往往會直接影響實驗結果；因此，在蒸發過程中如何控制懸浮粒子的分佈情形，是目前許多工業與科學研究極需研究探討的。 本論文實驗主要可分為基板清洗與液滴蒸發實驗兩部分。論文中透過不同的基板清洗方法，得到液滴蒸發過程中固定住與未固定住兩種蒸發型態之數據。在未清洗的玻璃基板或利用濕式清洗法清洗過之玻璃基板上進行蒸發實驗可觀察固定住的液滴蒸發型態，但其重複性不高；而利用氧氣電漿的清洗流程則能提供高重複性的玻璃基板清洗，可以使液滴在蒸發過程中不被固定住，而找出不同於前人的實驗結果，此外，經過氧氣電漿清洗過之ITO玻璃或塗佈鐵氟龍之疏水性基板也能出現相同不被固定住的結果。 此外，實驗中亦發現，液滴會不會被固定住除了與基板清洗方式有關之外，也與液滴內的微粒子濃度有關。在利用氧氣電漿清洗過之玻璃基板上，當液滴內微粒子濃度超過5×10-3%後，液滴在蒸發過程中便會出現明顯的固定段。在相同的環境壓力之下，當微粒子濃度增高時，面積縮減終端速度有增加的趨勢，而在低壓狀態下亦同；若比較相同濃度的條件下，0.4大氣壓下的終端速度增高為一大氣壓下終端速度的三倍，但很明顯地並環境壓力不影響液滴是否固定住的現象。Droplet evaporation is a basic natural phenomena, and has a lot of applications. In many experiment procures, reside effects the result. Therefore, it is important to know how to control distribution of particles in industry or in research. There are two main parts in this journal, the first one is the substrate cleaning and the second is droplet evaporation. We improve there are two distinct behaviors on different cleaning substrates when evaporating. When droplet evaporates on unclean or wet clean substrate, the droplet pins with bad repeatability; on the other hand, dry clean gets unpin type with repeatability. It also be found on hydrophobic substrates. Besides, pining is relative to particle concentration. When particle concentration is more than 5×10-3%, the unpin droplet is pinned on cleaning substrates. Concentration increases, terminal area shrink velocity at the same pressure increases, too; under the same concentration, terminal area shrink velocity at 0.4 atm is triple that at 1atm.摘要 I Abstract II 誌謝 III 目錄 IV 圖表目錄 VI 表格目錄 IX 符號說明 X 第 壹 章 緒論.........................................................................................................................01 1.1 前言...............................................................................................................................01 1.2 研究動機.......................................................................................................................01 1.3 文獻回顧.......................................................................................................................04 第 貳 章 實驗儀器架設........................................................................................................08 2.1 真空恆溫恆濕系統......................................................................................................08 2.2 液滴產生技術..............................................................................................................10 2.2.1 壓力式.................................................................................................................11 2.2.2 熱氣泡式............................................................................................................11 2.2.3 壓電式.................................................................................................................12 2.2.4 其他.....................................................................................................................13 2.3 影像分析處理..............................................................................................................15 第 參 章 基板清洗................................................................................................................18 3.1 清洗方法介紹..............................................................................................................18 3.2 基板清洗結果..............................................................................................................19 3.3 基板材質......................................................................................................................26 第 肆 章 液滴蒸發實驗........................................................................................................29 4.1 毛細管流觀測..............................................................................................................29 4.2 液滴蒸發實驗..............................................................................................................31 4.2.1 粒子濃度............................................................................................................31 4.2.2 環境壓力............................................................................................................34 4.3 蒸發實驗分析..............................................................................................................35 第 伍 章 結論與未來發展....................................................................................................40 第 陸 章 參考文獻................................................................................................................41 附錄............................................................................................................................................432759977 bytesapplication/pdfen-US液滴蒸發基板清洗粒子濃度環境壓力Droplet evaporationSubstrate cleaningParticle concentrationPressurethesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/62574/1/ntu-94-R92543061-1.pdf