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Prediction of 3D transversal patterns in packed - bed reactors using a reduced 2D model / Olga Nekhamkina in Industrial & engineering chemistry research, Vol. 49 N° 21 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10558-10564 Titre : Prediction of 3D transversal patterns in packed - bed reactors using a reduced 2D model : Oscillatory kinetics Type de document : texte imprimé Auteurs : Olga Nekhamkina, Auteur ; Moshe Sheintuch, Auteur Année de publication : 2011 Article en page(s) : pp. 10558-10564 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Kinetics  Two  dimensional  model  Fixed  bed  reactor  Prediction Résumé : We have recently showed the formation of transversal patterns in a 3D cylindrical reactor in which an exothermic first-order reaction of Arrhenius kinetics occurs with variable catalytic activity. Under these oscillatory kinetics, the system exhibits a planar front (1D) solution, with the front position oscillating in the axial direction, while in the 3D case, three types of transversal patterns can emerge: rotating fronts, oscillating fronts with superimposed transversal (nonrotating) oscillations, and mixed rotating-oscillating fronts. In the present study, we analyze the possible reduction of the 3D model to a 2D cylindrical shell model to predict patterns. We map bifurcation diagrams showing domains of different modes using the reactor radius (R) as a bifurcation parameter and show that the front divergence and the domains of the kn-mode pattern in the 3D model [corresponding to the transversal eigenfunction Jk(μknr) exp(ikθ), in which Jk is the Bessel function of the first kind] can be predicted by those of the one wave in the 2D model using the linear transformation R3D = μknR2D. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447948 [article] Prediction of 3D transversal patterns in packed - bed reactors using a reduced 2D model : Oscillatory kinetics [texte imprimé] / Olga Nekhamkina, Auteur ; Moshe Sheintuch, Auteur . - 2011 . - pp. 10558-10564. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10558-10564 Mots-clés : Kinetics  Two  dimensional  model  Fixed  bed  reactor  Prediction Résumé : We have recently showed the formation of transversal patterns in a 3D cylindrical reactor in which an exothermic first-order reaction of Arrhenius kinetics occurs with variable catalytic activity. Under these oscillatory kinetics, the system exhibits a planar front (1D) solution, with the front position oscillating in the axial direction, while in the 3D case, three types of transversal patterns can emerge: rotating fronts, oscillating fronts with superimposed transversal (nonrotating) oscillations, and mixed rotating-oscillating fronts. In the present study, we analyze the possible reduction of the 3D model to a 2D cylindrical shell model to predict patterns. We map bifurcation diagrams showing domains of different modes using the reactor radius (R) as a bifurcation parameter and show that the front divergence and the domains of the kn-mode pattern in the 3D model [corresponding to the transversal eigenfunction Jk(μknr) exp(ikθ), in which Jk is the Bessel function of the first kind] can be predicted by those of the one wave in the 2D model using the linear transformation R3D = μknR2D. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447948