Droplets in sprays

Trapaga and Szekely 515 conducted a mathematical modeling study of the isothermal impingement of liquid droplets in spray processes using a commercial CFD code called FLOW-3D. Their model is similar to that of Harlow and Shannon 397 except that viscosity and surface tension were included and wetting was simulated with a contact angle of 10°. In a subsequent study, 371 heat transfer and solidification phenomena were also addressed. These studies provided detailed... 

Visual comparison of the holographically recorded radiation pattern of a particle with Mie theory has also been used for particle sizing [71]. Holography has also been used to locate sub-micron particles in a 3-dimensional volume [72] and, in conjunction with an image analyzing computer, to size the droplets in sprays [73]. 

The above-considered model encourages one to develop a more complex model of the real behaviour of droplets in spraying systems. In fact, nozzles produce droplets in different directions, some downwind and another upwind. 

Qservation of Morphology and Flavor Droplets IN Spray-Dried Particles by CLSM... 

FIGURE 45.10 Droplet temperature T and thermal degradation Aj. in maltose-water system vs. reduced time t/R for two air temperatures (1) to 100°C, and (2) to 80°C. (From Kerkhof, P.J.A.M. and Schoeber, W.J.A.H., Theoretical modeling of the drying behavior of droplets in spray dryers, in Advances in Preconcentration and Dehydration of Foods, A. Spicer (Ed.), Elsevier Applied Science, London, U.K., pp. 349-397, 1974. With permission.)... 

P.J.A.M. Kerkhof, W.J.A.H. Schoeber, Theoretical Modeling of the Drying Behavior of Droplets in Spray Dryers, in Advances in Preconcentration and Dehydration of Foods, A. Spicer (Ed.), Elsevier AppHed Science Publishers, London, 349 397 (1974). 

Shekel, W., Huber, M., Hirschler, M., Kunz, P., Nieken, U. (2014) Drying and morphology evolution of single droplets in spray processes. In 9th SPHERIC International Workshop, Paris, France, 3-5 June, 2014. 

Golman, B. (2011). Modeling of the drying kinetics of slurry droplet in spray drying. AJChE Journal, 11, 1-7. 

The aim of this numerical study is to analyze the effects of the grouping/clustering of droplets in sprays on the heat transfer. In this study an Euler-Lagrangian algorithm is used to simulate the droplet-gas interactions. The droplets are assumed spherical with a radius smaller than the smallest length scale of the turbulence and a density much larger than that of the ambient gas. The heat transfer of individual droplets is characterized by the Nusselt number, which is defined by the... 

Also, the formation of droplets in spray processes is controlled by interfacial phenomena revealing at high pressures. Falling droplets are characterized by the Weber number. 

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