水添加界面活性劑碰撞現象之觀察

液滴碰撞之實驗可藉碰撞參數與韋伯數將其現象分為五個區域，（I）兩液滴微量變形後結合；（II）彈開；（III）兩液滴歷經顯著變形後結合；(IV)正撞拉伸分離；（V）擦撞拉伸分離，根據前人之實驗，水在一大氣壓空氣中碰撞，不會出現彈開之碰撞現象，僅會出現（I）、（IV）、（V）三種現象。在本實驗中，於水中加入界面活性劑，Triton X100，以改變表面張力。觀察其碰撞現象，此時可發現有彈開之碰撞現象，且隨著表面張力的改變，各種碰撞現象區域之分界也會跟著改變，本實驗即在探討表面張力之改變對邊界之影響。

關鍵字

液滴碰撞；界面活性劑；水

並列摘要

The boundaries of droplet collision phenomena are defined by Weber number and Impact parameter, namely(I) coalescence after minor deformation, (II) bouncing, (III) coalescence after substantial deformation, (IV) coalescence followed by separation for near head-on collisions, and (V) coalescence followed by separation for off-centre collisions. According to earlier investigation, bouncing collision of water is not observed at 1 atm. Air. In this experiment, the surfactant, Triton X100, is dissolved in water in order to change the surface tension. Observing its collision phenomena, we can find bouncing collision and the boundaries of collision is changed. The influence of the surface tension on the boundaries of droplet collision will be discussed in this experiment.

並列關鍵字

droplet collision ； surfactant ； water

參考文獻

1. J. R. Adam, N. R. Lindblad, and C. D. Hendricks, “The Collision, Coalescence and Disruption of Water Droplets,” Journal of Applied Physics, Vol.39, No.11,pp.5173-5180 （1968）.

2. D. M. Whelpdale and R. List, “The Coalescence in Raindrop Growth,” Journal of Geophysics Research, Vol.76, No.12, pp.2386-2856（1971）.

3. T. B. Low and R. List, “Collision, Coalescence and Backup of Raindrops. Part 2:Parameterization of Fragment Size Distribution,” J. Atm. Sci., Vol. 39, pp. 1607-1618（1982）

4. G. Brenn and A. Frohn, “Collision and Merging of Two Equal Droplets of Propanol,” Experiments in Fluids, Vol. 7, pp.441-446 （1989）.

5. N. Ashgriz and P. Givi, “Coalescence Efficiencies of Fuel Droplets in Binary Collisions,” International Communication of Heat and Mass Transfer, Vol.16, pp.11-20 （1989）.

國際替代計量

水添加界面活性劑碰撞現象之觀察

全文下載

主題瀏覽