Effects of using two versus threedimensional computational modeling of fluidized beds Part I, hydrodynamics
Abstract
Simulations of fluidized beds are performed to study and determine the effect on the use of coordinate systems and geometrical configurations to model fluidized bed reactors. Computational fluid dynamics is employed for an EulerianEulerian model, which represents each phase as an interspersed continuum. The transport equation for granular temperature is solved and a hyperbolic tangent function is used to provide a smooth transition between the plastic and viscous regimes for the solid phase. The aim of the present work is to show the range of validity for employing simulations based on a 2D Cartesian coordinate system to approximate both cylindrical and rectangular fluidized beds. Three different fluidization regimes, bubbling, slugging and turbulent regimes, are investigated and the results of 2D and 3D simulations are presented for both cylindrical and rectangular domains. The results demonstrate that a 2D Cartesian system can be used to successfully simulate and predict a bubbling regime. However, caution must be exercised when using 2D Cartesian coordinates for other fluidized regimes. A budget analysis that explains all the differences in detail is presented in Part II [N. Xie, F. Battaglia, S. Pannala, Effects of Using TwoVersus ThreeDimensional Computational Modeling of Fluidized Beds: Part II, budget analysis, 182more »
 Authors:
 Iowa State University
 ORNL
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 FE USDOE  Office of Fossil Energy (FE)
 OSTI Identifier:
 931149
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Powder Technology; Journal Volume: 182; Journal Issue: 1
 Country of Publication:
 United States
 Language:
 English
 Subject:
 42 ENGINEERING; 01 COAL, LIGNITE, AND PEAT; CARTESIAN COORDINATES; COMPUTERIZED SIMULATION; FLUID MECHANICS; FLUIDIZED BEDS; HYDRODYNAMICS; FLOW MODELS; TWODIMENSIONAL CALCULATIONS; THREEDIMENSIONAL CALCULATIONS; CYLINDRICAL CONFIGURATION; RECTANGULAR CONFIGURATION
Citation Formats
Xie, Nan, Battaglia, Francine, and Pannala, Sreekanth. Effects of using two versus threedimensional computational modeling of fluidized beds Part I, hydrodynamics. United States: N. p., 2008.
Web. doi:10.1016/j.powtec.2007.07.005.
Xie, Nan, Battaglia, Francine, & Pannala, Sreekanth. Effects of using two versus threedimensional computational modeling of fluidized beds Part I, hydrodynamics. United States. doi:10.1016/j.powtec.2007.07.005.
Xie, Nan, Battaglia, Francine, and Pannala, Sreekanth. 2008.
"Effects of using two versus threedimensional computational modeling of fluidized beds Part I, hydrodynamics". United States.
doi:10.1016/j.powtec.2007.07.005.
@article{osti_931149,
title = {Effects of using two versus threedimensional computational modeling of fluidized beds Part I, hydrodynamics},
author = {Xie, Nan and Battaglia, Francine and Pannala, Sreekanth},
abstractNote = {Simulations of fluidized beds are performed to study and determine the effect on the use of coordinate systems and geometrical configurations to model fluidized bed reactors. Computational fluid dynamics is employed for an EulerianEulerian model, which represents each phase as an interspersed continuum. The transport equation for granular temperature is solved and a hyperbolic tangent function is used to provide a smooth transition between the plastic and viscous regimes for the solid phase. The aim of the present work is to show the range of validity for employing simulations based on a 2D Cartesian coordinate system to approximate both cylindrical and rectangular fluidized beds. Three different fluidization regimes, bubbling, slugging and turbulent regimes, are investigated and the results of 2D and 3D simulations are presented for both cylindrical and rectangular domains. The results demonstrate that a 2D Cartesian system can be used to successfully simulate and predict a bubbling regime. However, caution must be exercised when using 2D Cartesian coordinates for other fluidized regimes. A budget analysis that explains all the differences in detail is presented in Part II [N. Xie, F. Battaglia, S. Pannala, Effects of Using TwoVersus ThreeDimensional Computational Modeling of Fluidized Beds: Part II, budget analysis, 182 (1) (2007) 14] to complement the hydrodynamic theory of this paper.},
doi = {10.1016/j.powtec.2007.07.005},
journal = {Powder Technology},
number = 1,
volume = 182,
place = {United States},
year = 2008,
month = 1
}

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