本文主要探討異質液滴撞擊深池液面之撞擊現象。實驗上主要是以水滴分別撞擊三種表面張力幾乎相同而黏滯性有明顯差異的液體表面包括柴油、沙拉油及針車油，藉由高速攝影機觀察撞擊後水滴與油液面的變化，探討項目包含撞擊後水滴的變化、撞擊油面形成的空穴成長的情形以及水滴在液面下碎裂的狀況。
研究結果發現空穴的發展與韋伯數有較直接的關係。針對不同黏滯係數而言，當被撞擊流體的黏滯係數較低時(柴油、針車油)，在低韋伯數（低撞擊動能）的情況下空穴會有頸縮現象發生，頸縮的現象到高韋伯數（高撞擊動能）隨即消失；當被撞擊流體的黏滯性較高時（沙拉油），尚未觀測到類似頸縮的現象。當水滴撞擊這三種黏滯係數的工作流體時，在撞擊動能足夠的情況下，都會在液面上拉出含水複合液滴。在本實驗當中，當黏滯係數較低（柴油）的情況下，水滴在液面下破碎的顆粒數隨著韋伯數逐漸以非線性增加，在特定範圍的韋伯數其顆粒數達到最高，並非單純隨著韋伯數的提高而增加；且顆粒尺寸皆達到最低。當黏滯係數較高（針車油、沙拉油）的情況下以目前實驗的範圍所見顆粒數只有隨著韋伯數提高而逐漸增加的趨勢；但是，當水滴在高韋伯數撞擊高黏滯係數（沙拉油）液面時，水滴破碎情形遠比柴油和針車油更為明顯。

A water drop impacting on a deep immiscible liquid pool was experimentally conducted in this study. Three liquids were served as target liquids, namely, diesel oil, salad oil and light lubricating oil. The surface tensions of these oils are almost the same, but the viscosities are very different. By using high speed video-camera, the deformation of the incoming water drop, the evolution of the cavity, and the disintegration of the water drop under the pool surface were investigated.
Based on the experimental results, we found that the evolution of the cavity depended on the impacting Weber number and the viscosity. For a target liquid with lower viscosity, namely, diesel oil and light lubricating oil, a necking on the cavity was observed while the impacting Weber number of the water drop was low. In contract, the necking disappeared for higher impacting Weber number. On the other hand, for a target liquid with higher viscosity, namely, salad oil, the necking was not observed. For all three target liquids, a compound jet composed of the incoming liquid and target liquid ejected from the pool surface and broke into compound drops when the impact energy of the incoming drop was high enough.
Under the pool surface, we counted the numbers of the tiny drop which came from the disintegration of the impacting water drop. For the diesel oil served as target liquid, the numbers of the tiny drop increased as the impacting Weber increased until a specific regime where the numbers of the tiny drop was maximal reached. Also, the size of the tiny drop was minimal in this specific regime. For the salad oil and light lubricating oil served as target liquid, the numbers of the tiny drop increased as the impacting Weber increased under the experimental condition in this study. In addition, the disintegration of the incoming water drop under the pool surface was more obvious when the water impacted on the salad oil than on the diesel oil or on the light lubricating oil.

目　　次
摘要 Ⅰ
英文摘要 Ⅱ
誌謝 Ⅲ
目次 Ⅳ
圖目錄 Ⅵ
表目錄 Ⅶ
第一章 前言 1
1-1 文獻回顧 2
1-2 研究目的 6
第二章 實驗設備與儀器 8
2-1液滴產生系統 8
2-2攝影及記錄系統 9
2-3玻璃油槽 10
2-4高度調整系統 11
第三章 實驗原理與步驟 12
3-1液滴撞擊現象之控制參數 12
3-2實驗參數的量測 12
3-3實驗步驟 13
3-4影像擷取與處理 15
第四章 實驗結果與討論 16
4-1水滴撞擊三種不同黏滯性液面之撞擊型態 16
4-1-1水滴撞擊柴油液面之撞擊型態 16
4-1-2水滴與針車油液面之撞擊型態 19
4-1-3水滴與沙拉油液面之撞擊型態 20
4-2水滴撞擊三種油類之破碎水滴尺寸與顆粒數量統計 21
4-2-1水滴撞擊柴油液面 22
4-2-2水滴撞擊針車油液面 23
4-2-3水滴撞擊沙拉油液面 23
第五章 結論 24
第六章 複合液滴撞擊液面現象的初探 27
6-1實驗設備與儀器 27
6-1-1液滴產生系統 27
6-1-2攝影及記錄系統 28
6-1-3玻璃油槽 29
6-1-4高度調整系統 29
6-2實驗原理與步驟 29
6-2-1複合液滴撞擊現象之控制參數 29
6-2-2實驗參數的量測 30
6-2-3實驗步驟 31
6-2-4影像擷取與處理 31
6-3結果與討論 31
6-4結論 32
參考文獻 33

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