Abstract
The horizontal diffusion of coarse particles in dense fluidized beds is commonly used for particle mixing and discharging in CFB boilers. However, numerical modeling of such flows is hard at present because of the flow complexity and a lack of reliable methods. In this work, a TFM-DEM hybrid model is used to study the diffusion behavior of coal particle in a dense fluidized bed. The gas phase and the solid medium phase are modeled by the TFM, while the coal particles are modeled by the DEM. The TFM can give a reliable description of the dense medium flow while the DEM can readily designate the size and density distributions of the coarse particles. The diffusion pattern of the particles with different size and density is mainly studied. Influence factors such as the fluidized air velocity and the coal particle number are also investigated. To explain the mechanisms of particle diffusion in the dense bed, main forces exerted on the coal particles are analyzed in the Lagrangian framework.
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References
Mohanta S, Rao CS, Daram AB et al (2013) Air dense medium fluidized bed for dry beneficiation of coal: technological challenges for future. Part Sci Technol 31:16–27
Sahu AK, Biswal SK, Parida A (2009) Development of air dense medium fluidized bed technology for dry beneficiation of coal—a review. Int J Coal Prep Util 29:216–241
Wang QG, Lu JF, Yin WD, Yang HR, Wei LB (2013) Numerical study of gas-solid flow in a coal beneficiation fluidized bed using kinetic theory of granular flow. Fuel Process Technol 111:29–41
Zhao Y, Tang L, Luo Z et al (2010) Experimental and numerical simulation studies of the fluidization characteristics of a separating gas–solid fluidized bed. Fuel Process Technol 91:1819–1825
Wang Q, Feng Y, Lu J et al (2015) Numerical study of particle segregation behaviors in a coal beneficiation fluidized bed by a TFM-DEM hybrid model: influence of coal particle size and density. Chem Eng J 260:240–257
Gidaspow D (1994) Multiphase flow and fluidization: continuum and kinetic theory descriptions. Academic, Boston
Feng Y, Yu A (2007) Microdynamic modelling and analysis of the mixing and segregation of binary mixtures of particles in gas fluidization. Chem Eng Sci 62:256–268
Cundall PA, Strack ODL (1978) The distinct element method as a tool for research in granular media, Tech. Rep. NSF Grant ENG76-20711, National Science Foundation
Syamlal M (1987) The particle-particle drag term in a multiparticle model of fluidization. National Technical Information Service, Springfield, p 188
Johnson PC, Jackson R (1987) Frictional–collisional constitutive relations for granular materials, with application to plane shearing. J Fluid Mech 176:67–93
Acknowledgments
This work was supported by the Key Basic Research Project (973 Program) of China (No. 2012CB214900).
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© 2016 Springer Science+Business Media Singapore and Tsinghua University Press
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Wang, Q.G., Yin, W.D., Lu, J.F., Yang, H.R. (2016). Numerical Study of the Multiphase Gas–Solid Flow by a TFM-DEM Hybrid Model. In: Yue, G., Li, S. (eds) Clean Coal Technology and Sustainable Development. ISCC 2015. Springer, Singapore. https://doi.org/10.1007/978-981-10-2023-0_73
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DOI: https://doi.org/10.1007/978-981-10-2023-0_73
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