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中文提要:實驗的結果發現,純水的液膜型態隨著噴流速度的變化區分為 四種模式:封閉液緣與週期性掉落模式;-封閉液緣與散射液滴模式;R開 放液緣與散射液滴模式;‾完全發展模式。而高黏滯性液體形成之液膜型 態隨著噴流速度的變化共區分為九種模式:階梯式封閉液緣模式;-封閉 液緣模式;R封閉液緣與穿孔破裂模式;‾週期性掉落模式;°開放液緣 模式;±開放液緣與穿孔破裂模式;2開放液緣與散射液滴模式;3開放液 緣、散射液滴與穿孔破裂模式;’完全發展模式。在較小的噴流速度下, 霧化液滴的平均粒徑隨著液體黏滯性與表面張力的增加而變大。但是在較 高的噴流速度下,霧化液滴的平均粒徑與液體的黏滯性及表面張力無關, 皆趨近於50mm。 英文提要:The results show that there are four spray patterns formed by impinging-jetproduced by pure water jets presented in sequence with increasing jetsvelocities. They are defined as (1) close-rim with periodic-drops, (2)close-rim with shedding-drops, (3) open-rim with shedding-drops, and (4) fully-developed. On the other hand, there are nine spray patterns formed by high viscosity fluids, which are defined as (1) close-rim with cascade,(2) close-rim, (3) close-rim with perforate, (4) periodic-drops, (5) open-rim, (6) open-rim with perforate, (7) open-rim with shedding-drops, (8) open-rim with shedding-drops and perforate, and (9) fully-developed .With the measurement of Malvern particle sizer, the mean drop size is bigger as the viscosity and surface-tension of the working fluid getting higher at lower impinging-jet velocity regime. However, it is atomized intoabout 50mm droplets at high impinging-jet velocity regime which is independent on the physical properties of the working fluid.
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