Fluidization and heat transfer

Gidaspow, D. Hydrodynamics of fluidization and heat transfer Supercomputer modeling, Appl. Mech. Rev. 39, 1-22 (1986). 

Canada GS, MacLaughlin MH. Large particle fluidization and heat transfer at high pressure. AIChE Symp Ser 74 (176)27 37, 1978. 

Gan JQ Discrete particle simulation of packing, fluidization and heat transfer of ellipsoids, Melbonme, Australia, 2015, Monash University. 

Gas—solids fluidization is the levitation of a bed of solid particles by a gas. Intense soflds mixing and good gas—soflds contact create an isothermal system having good mass transfer (qv). The gas-fluidized bed is ideal for many chemical reactions, drying (qv), mixing, and heat-transfer appHcations. Soflds can also be fluidized by a Hquid or by gas and Hquid combined. Liquid and gas—Hquid fluidization appHcations are growing in number, but gas—soHds fluidization appHcations dominate the fluidization field. This article discusses gas—soHds fluidization. 

Mass and Energy Balances Due to the good mixing and heat-transfer properties of fluidized beds, the exit-gas temperature is assumed to be the same as the bed temperature. Fluidized bed gran-... 

The essential feature of a Jluidized-bed reactor is that the solids are held in suspension by the upward flow of the reacting fluid this promotes high mass and heat transfer rates and good mixing. Heat transfer coefficients in the order of 200 W/m-°C between jackets and internal coils are typically obtained. The solids may be a catalyst, a reactant (in some fluidized combustion processes), or an inert powder added to promote heat transfer. 

To provide the pr equisite knowledge for designing the three-phase fluidized-bed reactors with new modes, the hydrodynamics such as phase holdup, mixing and bubble properties and heat and mass transfer characteristics in the reactors have to be determined. Thus, in this study, the hydrodynamics and heat and mass transfer characteristics in the inverse and circulating three-phase fluidized-bed reactors for wastewater treatment in the present and previous studies have been summarized. Correlations for the hydrod3aiamics as well as mass and heat transfer coefficients are proposed. The areas wherein future research should be undertaken to improve... 

Correlations for Mass and Heat Transfer Factors in Fluidized Beds... 

Noymer, P. D., Hyre, M. R., and Glicksman, L. R., The Influence of Bed Diameter on Hydrodynamics and Heat Transfer in Circulating Fluidized Beds, Fluidization and Fluid-Particle Systems, AIChE, pp. 86-90 (1995)... 

Dou, S., Herb, B., Tuzla, K., and Chen, J. C., Dynamic Variation of Solid Concentration and Heat Transfer Coefficient at Wall of Circulating Fluidized Bed, Fluidization VII, 793-801 (1993)... 

Tamarin, A. I., Zabrodsky, S. S., and Yepanov, G., Heat Transfer Between a Horizontal Staggered Tube Bundle and a Fluidized Bed, Heat Transfer-Soviet Research, 8(5) 51—55 (1976)... 

Werdmann, C. C., and Werther, J., Solids Flow Pattern and Heat Transfer in an Industrial Scale Fluidized Bed Heat Exchanger, Proc. 12th Intern. Conf. on Fluid. Bed Comb., 2 985-990 (1993)... 

Wood, R. T., Staub, F. W., Canada, G. S., and McLaughlin, M. H., Two-Phase Flow and Heat Transfer in Fluidized Beds, Technical Report, RP 525-1, General Electric Co., Schenectady, NY (1978)... 

In system 1, the 3-D dynamic bubbling phenomena in a gas liquid bubble column and a gas liquid solid fluidized bed are simulated using the level-set method coupled with an SGS model for liquid turbulence. The computational scheme in this study captures the complex topological changes related to the bubble deformation, coalescence, and breakup in bubbling flows. In system 2, the hydrodynamics and heat-transfer phenomena of liquid droplets impacting upon a hot flat surface and particle are analyzed based on 3-D level-set method and IBM with consideration of the film-boiling behavior. The heat transfers in... 

GLS fluidized with a stable level of catalyst. Only the fluid mixture leaves the vessel. Gas and liquid enter at the bottom. Liquid is continuous, gas is dispersed. Particles are larger than in bubble columns, 0.2-1.0 mm. Bed expansion is small. Bed temperatures are uniform within 2 C in medium size beds, and heat transfer to embedded surfaces is excellent. Catalyst may be bled off and replenished continuously, or reactivated continuously. 

Zabrodsky, S. S. Hydrodynamics and Heat Transfer in Fluidized Beds (The M.I.T. Press, 1966). 

The relation between the transfer coefficient and thermal fluctuations in fluidized-bed heat transfer. 

Figure 3.9 Influence of product thickness and heat transfer coefficient on mean freezing rate for potato slices. From Rios, G.M., Marin, M. and Gibert, H., New developments of fluidization in the IQF food area, in McKenna, B.M., (ed.). Engineering and food, volume 2, processing applications, International Congress on Engineering and Food, 1983, Elsevier, 1984, figure 3. With kind permission of Springer Science and Business Media.

Fluid-solid mass and heat transfer in particulate fluidization... 

The literature of fluidization phenomena and technology is extensive. A good although dated bibliography is in Ullmann s Encyclopedia (1973, Vol. 3, pp. 458-460). The book by Chere-misinoff and Cheremisinoff (1984) has more than 500 abstracts of articles on fluidization hydrodynamics, mixing and heat transfer, but little on reactor technology. Other literature on fluidization is cited in the References of Chapter 6. 

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