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The phenomenon of droplets impact on a solid surface can be seen in many industrial applications. This phenomenon becomes more complex when droplets interact with a hot surface and/or other droplets. After multiple droplet impingement on a solid surface, an interaction occurs depending on the impact conditions of the droplets and the distance between them. This interaction leads to an uprising layer which causes lesser spreading area per droplet on solid surface. The hydrodynamic outputs and heat transfer activities of the droplets are very distinct from single droplet cases due to this interaction. Difficulties in understanding and modeling the physical mechanisms that take place in the spray cooling phenomenon arise from the randomness and untraceable behavior of the droplets. Therefore, the complex structure has been simplified and the interactions of multiple droplets have been numerically investigated using the volume of fluid (VOF) method. The aim of this study is to examine the effect of droplet number and droplet impact conditions on the heat transfer performance from the surface. [ABSTRACT FROM AUTHOR]

Microencapsulation is a covering process of solid, liquid or gas particules with polymer capsules or a thin film layer to protect these molecules from environment conditions and provide the stability. Several bioactive components in food products such as fat, enzymes, vitamins and minerals, some probiotic microorganisms and medicine that may be damaged in gastrointestinal tract, could be protected with microencapsulation. Also, arise of enzyme and catalyzators, that are not desired to be free in environment, could be limited or could be fastened as occasions requires, it can be said that encapsulation was a process to entrap active agent within another substance, in encapsulation technology, numerous wall materials such as carbonhydrates, gums, milk fat, proteins and protein based components; celluloses (carboxymethylcellulose, methyl cellulose, ethyl cellulose, nitro cellulose, acetyl cellulose, cellulose acetate butyrate) are used. There are many encapsulation techniques such as spray-drying, spray-bed-drying, fluid-bed coating, spray-chilling, spray-cooling, freeze-drying, extrusion, vacuum and melt injection. There is an important role of microencapsulation in dairy technology. In particularly, microencapsulation applications are very significant for flavour and aroma agents in cheese technology. It was reported that flavour, aroma and texture values of cheeses that include encapsulated enzyme was higher. Also it was seen that microencapsulation had prevented fast and extreme proteolysis in these chesses. In ice-cream, lactobacillus could be captured by encapsulation to remove the negative effects on lactic acid bacteria and so that alive probiotic microorganism count can be enhanced in ice cream. Studies about increasing resistance of milk fat and therefore prolonging the shelf life were done and positive results were found. Furthermore, it could be said that microencapsulation which is an alternative method in butter, both some aroma of milk fat and butter could be encapsulated. Also, microencapsulation is a significant technique for iron fortification in milk and milk products. [ABSTRACT FROM AUTHOR]