Heat Exchange Between Flow and Particles, Drops, or Bubbles

Mass and Heat Exchange Between Flow and Particles, Drops, or Bubbles 

The analysis of many technological processes involving dissolution, extraction, vaporization, combustion, chemical transformations in dispersions, sedimentation of colloids, etc. are based on the solution of the problem of mass exchange between particles, drops, or bubbles and the ambient medium. For example, in industry one often deals with processes of extraction from drops or bubbles or with heterogeneous transformations on the surface of catalyst particles suspended in a fluid. The rate of extraction and the intensity of a catalytic process to a large extent are determined by the value of the total diffusion flux of a reactant to the surface of particles of the disperse phase, which, in turn, depends on the character of flow and the particle shape, the influence of neighboring particles, the kinetics of the surface chemical reaction, and some other factors. 

The description of a number of meteorological phenomena is also based on the study of Brownian diffusion of aerosols to single solid and liquid particles. The increasing atmospheric pollution is a problem that requires understanding and description of the processes of atmospheric self-purification of chemical and mechanical pollutants and radioactive contaminants. The problem of settling aerosol particles on various collectors also arises in the analysis of filter efficiency. 

The results of investigation of similar convective heat transfer processes can be used in the design and analysis of heat exchangers. 

A number of physical and mathematical statements of problems on mass and heat exchange between particles, drops, or bubbles and flow, as well as various formulas and experimental data, can be found, for example, in the books [94, 166,255,270], 

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