本研究分別為不同乙醇濃度的液柱斷裂特性研究，以及水在不同流率(Q)、不同的液柱直徑(dj)和不同旋轉速度(ω)條件下的滴落特徵變化。不同乙醇濃度為工作流體，主要是探討流體性質變化對於液柱斷裂現象的影響性。研究結果顯示，乙醇濃度的變化會影響液柱的斷裂長度(Lj)；當乙醇濃度越高，液柱斷裂長度越長。此外，本研究另提出能夠預測不同乙醇濃度的液柱斷裂長度經驗公式。
水在不同流率(Q)和旋轉速度(ω)條件下的滴落特徵變化，主要是將噴嘴搭配一組可調速的旋轉機構，並改變不同的液柱直徑(dj)、流體流率(Q)與噴嘴旋轉速率(ω)，藉此探討滴落過程的液柱頂端長度(L)、左側偏移量(δd)以及毛細上升高度(δh)在整個滴落過程內的變化。研究結果顯示噴嘴旋轉速率(ω)和流體流率()均會影響斷裂時間間隔(tb)。同時噴嘴旋轉速率也會影響滴落的偏移量，轉速越高偏移現象越明顯；而管徑亦會影響液體的毛細上升現象，管徑越小毛細上升現象越明顯。

This research analyzes the breakup patterns of the ethanol-water jet of different volume concentration and the characteristic of a liquid jet under various conditions (e.g., various flow rates and rotating speeds). In the first part of the study, various concentrations of ethanol are used to analyze the characteristics of a liquid jet for various fluid properties and jet diameters. The surface tension is the main factor which causes the jet breakup. A smaller surface tension leads to a longer breakup length. The viscosity also has an effect. The breakup length of the fluid will slightly become longer if the fluid has a larger viscosity. A new correlation function is found based on the experimental data. The correlation works well for ethanol-water mixture, but it fails to predict the breakup length of water for small-diameter nozzles.
In the second part of the study, the characteristics of a dripping flow in a breakup process for various flow rates, rotating speeds, and inner nozzle diameters are investigated. It was found that the rotating speed and flow rate affect the breakup time. A high rotating speed causes an obvious deviation of the liquid column from the center-line of the nozzle. A more significant capillary rise occurs when the nozzle diameter is smaller. The parameters that make the breakup of the liquid column less stable are discussed.

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