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Fluid dynamic study of a semicylindrical spouted bed / Rodrigo Béttega in Industrial & engineering chemistry research, Vol. 48 N° 24 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 24 (Décembre 2009) . - pp. 11181–11188 Titre : Fluid dynamic study of a semicylindrical spouted bed : evaluation of the shear stress effects in the flat wall region using computational fluid dynamics Type de document : texte imprimé Auteurs : Rodrigo Béttega, Auteur ; Cezar A. da Rosa, Auteur ; Ronaldo G. Corrêa, Auteur Année de publication : 2010 Article en page(s) : pp. 11181–11188 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Cylindrical  vessels  Semicylindrical  spouted  beds  Computational  fluid  dynamics Résumé : Using a semicylindrical spouted bed to obtain experimental data of cylindrical vessels is an old technique and it has already been widely studied by experimental procedures. In the mathematical modeling of semicylindrical spouted beds, the specularity coefficient is one of the ways of including the effect of shear stress in the solid phase promoted by the flat wall. This parameter can be included in the boundary condition of a semicylindrical spouted bed to represent this friction effect. The main purpose of this paper is to discuss the numerical influence of the specularity coefficient on the fluid and solid dynamics of the semicylindrical vessel. Several numerical simulations were performed using the CFD (computational fluid dynamics) technique, by Euler−Euler 3D modeling, for different parameter values of the specularity coefficient. Experimental pressure data are used to verify these simulations. Numerical and experimental results showed good agreement, and the simulations indicated that particle velocity profiles and solid volume fraction were strongly influenced by the specularity coefficient on the spout channel region. Nonetheless, numerical static pressure and fluid velocity have not presented considerable dependence on this coefficient. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900973x [article] Fluid dynamic study of a semicylindrical spouted bed : evaluation of the shear stress effects in the flat wall region using computational fluid dynamics [texte imprimé] / Rodrigo Béttega, Auteur ; Cezar A. da Rosa, Auteur ; Ronaldo G. Corrêa, Auteur . - 2010 . - pp. 11181–11188. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 24 (Décembre 2009) . - pp. 11181–11188 Mots-clés : Cylindrical  vessels  Semicylindrical  spouted  beds  Computational  fluid  dynamics Résumé : Using a semicylindrical spouted bed to obtain experimental data of cylindrical vessels is an old technique and it has already been widely studied by experimental procedures. In the mathematical modeling of semicylindrical spouted beds, the specularity coefficient is one of the ways of including the effect of shear stress in the solid phase promoted by the flat wall. This parameter can be included in the boundary condition of a semicylindrical spouted bed to represent this friction effect. The main purpose of this paper is to discuss the numerical influence of the specularity coefficient on the fluid and solid dynamics of the semicylindrical vessel. Several numerical simulations were performed using the CFD (computational fluid dynamics) technique, by Euler−Euler 3D modeling, for different parameter values of the specularity coefficient. Experimental pressure data are used to verify these simulations. Numerical and experimental results showed good agreement, and the simulations indicated that particle velocity profiles and solid volume fraction were strongly influenced by the specularity coefficient on the spout channel region. Nonetheless, numerical static pressure and fluid velocity have not presented considerable dependence on this coefficient. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900973x

Fluid dynamics analysis of a draft-tube continuous spouted bed with particles bottom feed using CFD / Cezar A. da Rosa in Industrial & engineering chemistry research, Vol. 48 N° 16 (Août 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 16 (Août 2009) . - pp. 7813–7820 Titre : Fluid dynamics analysis of a draft-tube continuous spouted bed with particles bottom feed using CFD Type de document : texte imprimé Auteurs : Cezar A. da Rosa, Auteur ; José T. Freire, Auteur Année de publication : 2009 Article en page(s) : pp. 7813–7820 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Draft  tube  continuous  spouted  bed  Bottom  feed  Computational  fluid  dynamics Résumé : In this work the fluid dynamics behavior of a draft tube continuous spouted bed with particle bottom feed was studied through experimental data of static pressure, fountain height, and fluid mass flow in the annulus, as well as using the computational fluid dynamics. Experiments using glass beads as solid phase were carried out in two different velocity inlet conditions, 20 and 22 m/s. The inlet solid mass flow rate was 0.087 kg/s for the first case and 0.097 kg/s for the second one. Static pressure measurements were done in axial and radial coordinates for the entire equipment. The fountain height and fluid mass flow in the annulus were also evaluated during experiments. The Eulerian−Eulerian multifluid modeling approach was applied to predict gas−solid flow behavior. The Gidaspow (1994) drag model and the granular kinetic theory derived by Lun et al. (1984) were adopted here. A commercially available program, FLUENT 6.3, was chosen to carry out computer simulations. CFD simulations were able to predict very well the static pressure profile, fountain height, and fluid mass flow in the annulus. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900547u [article] Fluid dynamics analysis of a draft-tube continuous spouted bed with particles bottom feed using CFD [texte imprimé] / Cezar A. da Rosa, Auteur ; José T. Freire, Auteur . - 2009 . - pp. 7813–7820. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 16 (Août 2009) . - pp. 7813–7820 Mots-clés : Draft  tube  continuous  spouted  bed  Bottom  feed  Computational  fluid  dynamics Résumé : In this work the fluid dynamics behavior of a draft tube continuous spouted bed with particle bottom feed was studied through experimental data of static pressure, fountain height, and fluid mass flow in the annulus, as well as using the computational fluid dynamics. Experiments using glass beads as solid phase were carried out in two different velocity inlet conditions, 20 and 22 m/s. The inlet solid mass flow rate was 0.087 kg/s for the first case and 0.097 kg/s for the second one. Static pressure measurements were done in axial and radial coordinates for the entire equipment. The fountain height and fluid mass flow in the annulus were also evaluated during experiments. The Eulerian−Eulerian multifluid modeling approach was applied to predict gas−solid flow behavior. The Gidaspow (1994) drag model and the granular kinetic theory derived by Lun et al. (1984) were adopted here. A commercially available program, FLUENT 6.3, was chosen to carry out computer simulations. CFD simulations were able to predict very well the static pressure profile, fountain height, and fluid mass flow in the annulus. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900547u