الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
As per relevant literature, the principles of the liquid DROP ejection downstream weren’t covered well and the need for understanding the factors affecting this phenomenon has increased in the past decades. The purpose of the present thesis is to investigate the interaction between a plane air jet and a surface liquid drop. Firstly, an experimental method was followed to study the wettability effect on the DROP average velocity and its response time. Secondly, the ejection regimes associated with the drop-jet interaction were discussed briefly through several experiments and the phenomenon of the DROP splitting was presented against the previous arguments. Finally, a computational model through the ANSYS FLUENT was used to study the ejection regimes and the splitting phenomenon. Pairs of inclination angles and offset ratios were discussed and three different surface materials (Perspex, Glass and Nano-ceramic coated glass) with different texture roughness were considered. Besides, three liquids with different physical properties were tested on Perspex. Observations, analyses and conclusions using these two methods besides the recording tools showed that the wettability between the surface DROP and the impinging jet affect the ejection history. The velocity profiles were found to be dependent on the liquid properties and the surface texture roughness. For the same liquid, the wetting effect dominates the ejection process; the Perspex (the highest roughness) had an average DROP velocity 3 times that of Glass (the lowest roughness), and Nano-ceramic coated-glass (the lowest wetting surface) had 40% increase in the DROP average velocity over Perspex. On the other side, for the same surface; the liquid properties are dominating the ejection process over the wetting effect. Among the physical regimes; the DROP volume was found also affecting the ejection history, velocity profiles and the splitting occurrence. Finally, the geometrical orientation between the jet outlet and the DROP influences the ejection history, DROP average velocity, the physical regimes and the DROP splitting process. An increase of 25% in the DROP volume leads to a 50% increase, on average, in the DROP maximum Weber number. By using the volume of fluid (VOF) method; FLUENT was found to have the ability to simulate the ejection process and hence the physical regimes and the splitting phenomenon. This study presents insights into the interaction between a surface liquid DROP and a plane air jet and introduces a step on understanding the way by which a phenomenon such as the ejection of ocean water in the hurricanes, tornadoes and wind storms occurs.