Droplet solidification partial

Other t) es of interactions such as coalescence (Gurming et al., 2004a), depletion forces, or steric interactions on close approach of droplets can be studied by these methods. Thus, it is now possible to selectively modify the interfacial structure and to study the implications of such changes in terms of droplet interactions. For liquid fat droplets controlled (partial) coalescence, followed by solidification of the fat, is used to control aggregation or network formation, as a means of generating texture in whipped foods and ice creams. Partial coalescence should be particularly sensitive to the structure of mixed interfaces and the methods described above can be adapted to study this phenomenon. 

The method of liquid dynamic compaction (LDC) (Chin et al. 1986, Tanigawa et al. 1986) is based on the process of gas atomization (Anand et al. 1980). In gas atomization a stream of molten alloy is broken into a spray of fine particles by a jet of high-velocity gas and the rapidly solidified particles are collected. In LDC, a cooled substrate is placed beneath the atomization core at a distance such that most of the sprayed droplets are partially solidified. The rapidly solidified alloy builds up on the substrate at controllable rates, which can easily exceed 1 cm/min. Rapid solidification is made possible by the supercooling of the high-velocity atomized particles and the good thermal contact with a water-cooled copper substrate. 

The other group of collisions will result in particle partial penetration according to the Re—We regime map. Since most of colhsions in this regime occur in the downstream spray flow, it is considered reasonable that most of the solid particles are likely to be captured by the droplet surface because of droplet solidification. The sticking efficiency of particulate reinforcements on the surface of MMC particles can be roughly described by the volume fraction of these particles to the droplet. 

Partial Solidification prior to Impact Parti al solidification of an impacting droplet prior to impact is considered. 

Madejski s solidification model did not account for partial solidification of a droplet prior to impact. San Marchi et al.[157]... 

Fly ash particles are typically spherical, as they are formed by solidification of droplets of a partially melted material, suspended in the flue gas, upon cooling. Particles that are formed at lower combustion temperatures may be irregular, owing to the reduced amount of melt present. Occasionally, tiny grains of volatile salts may be deposited on the ash particle surface. About 20% of fly ash particles are hollow, owing to an entrapment of gases by the molten phase in the course of burning. They are called cenospheres. Some of them, called plerospheres, may contain smaller particles inside. 

Multiple emulsions that were solidified after preparation can suffer from destabilization effects. This phenomenon is scarcely considered, but in practice, it occurs very often. The solidification occurs because of temperature changes (temperatures can fluctuate from subzero of ca. -20°C to ca. 40°C) during transport or storage. Clausse et al. (Clausse, 1998 Clausse et al., 1999) studied the phenomena in W/OAV emulsions by microcalorimetric (DSC) techniques. It was concluded that out of thermodynamic equilibrium, multiple emulsions may suffer from water transfer during the solidification. This phenomenon occurs even if partial solidification takes place. In addition a change in the size distribution of emulsion droplets was observed. The mean diameter of the... 

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