Documents disponibles écrits par cet auteur

High - pressure methane combustion over a perovskyte catalyst / Paola S. Barbato in Industrial & engineering chemistry research, Vol. 51 N° 22 (Juin 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 22 (Juin 2012) . - pp. 7547–7558 Titre : High - pressure methane combustion over a perovskyte catalyst Type de document : texte imprimé Auteurs : Paola S. Barbato, Auteur ; Almerinda Di Benedetto, Auteur ; Valeria Di Sarli, Auteur Année de publication : 2012 Article en page(s) : pp. 7547–7558 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Combustion  Catalyst Résumé : Catalytic combustion has been extensively studied as an alternative route to homogeneous combustion for power generation systems, in particular for gas turbines. Despite the great interest, very little work has been devoted to high-pressure catalytic combustion, i.e., under conditions more relevant for gas turbines. In this work, the effect of pressure on the catalytic combustion of methane on a perovskite-based monolith is investigated both experimentally and numerically. Results show that methane can be ignited by increasing the operating pressure, and this behavior can be reproduced qualitatively and quantitatively by simulating the monolith using simple overall homogeneous and heterogeneous reaction rates. Moreover, numerical results show that only the coupling between catalytic and homogeneous reactions allows correct prediction of methane conversion. As the operating pressure increases, the catalytic reaction is activated, thus behaving as a pilot for sustaining the homogeneous reaction that allows it to overcome the mass transport limitations at the catalytic surface. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201736p [article] High - pressure methane combustion over a perovskyte catalyst [texte imprimé] / Paola S. Barbato, Auteur ; Almerinda Di Benedetto, Auteur ; Valeria Di Sarli, Auteur . - 2012 . - pp. 7547–7558. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 22 (Juin 2012) . - pp. 7547–7558 Mots-clés : Combustion  Catalyst Résumé : Catalytic combustion has been extensively studied as an alternative route to homogeneous combustion for power generation systems, in particular for gas turbines. Despite the great interest, very little work has been devoted to high-pressure catalytic combustion, i.e., under conditions more relevant for gas turbines. In this work, the effect of pressure on the catalytic combustion of methane on a perovskite-based monolith is investigated both experimentally and numerically. Results show that methane can be ignited by increasing the operating pressure, and this behavior can be reproduced qualitatively and quantitatively by simulating the monolith using simple overall homogeneous and heterogeneous reaction rates. Moreover, numerical results show that only the coupling between catalytic and homogeneous reactions allows correct prediction of methane conversion. As the operating pressure increases, the catalytic reaction is activated, thus behaving as a pilot for sustaining the homogeneous reaction that allows it to overcome the mass transport limitations at the catalytic surface. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201736p

Sensitivity to the presence of the combustion submodel for large eddy simulation of transient premixed flame – vortex interactions / Valeria Di Sarli in Industrial & engineering chemistry research, Vol. 51 N° 22 (Juin 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 22 (Juin 2012) . - pp. 7704–7712 Titre : Sensitivity to the presence of the combustion submodel for large eddy simulation of transient premixed flame – vortex interactions Type de document : texte imprimé Auteurs : Valeria Di Sarli, Auteur ; Almerinda Di Benedetto, Auteur Année de publication : 2012 Article en page(s) : pp. 7704–7712 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Combustion  Transient  flame Résumé : In this paper, the sensitivity of large eddy simulation (LES) to the presence of the combustion submodel was investigated for transient interactions between premixed flame fronts and toroidal vortex structures generated at the wake of a circular orifice. To this end, LES computations were run, with and without the combustion submodel, for two orifice diameters: 40 mm and 20 mm. Nonuniform unstructured grids with a cell characteristic length varying in the range of 0.5–1 mm were used. In going from the 40-mm orifice to the 20-mm orifice, both the size and velocity of the vortex increase, leading to a different regime of interaction with the flame: the vortex only wrinkles the flame front in the 40-mm case (wrinkled regime) and also disrupts the continuity of the front, giving rise to the formation of separate reaction zones (i.e., flame pockets that leave the main front), in the 20-mm case (breakthrough regime). It has been found that the impact of the combustion submodel on LES predictions is strongly dependent on the regime of interaction. Results for the 40-mm orifice are substantially the same, regardless of the presence of the combustion submodel. Conversely, at the wake of the 20-mm orifice, the intensity of the flame–vortex interaction is such that the combustion submodel is strictly needed to reproduce both the qualitative (evolution of the pockets formed and their interaction with the main front) and quantitative (flame speed) characteristics of the flame propagation correctly. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202061u [article] Sensitivity to the presence of the combustion submodel for large eddy simulation of transient premixed flame – vortex interactions [texte imprimé] / Valeria Di Sarli, Auteur ; Almerinda Di Benedetto, Auteur . - 2012 . - pp. 7704–7712. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 22 (Juin 2012) . - pp. 7704–7712 Mots-clés : Combustion  Transient  flame Résumé : In this paper, the sensitivity of large eddy simulation (LES) to the presence of the combustion submodel was investigated for transient interactions between premixed flame fronts and toroidal vortex structures generated at the wake of a circular orifice. To this end, LES computations were run, with and without the combustion submodel, for two orifice diameters: 40 mm and 20 mm. Nonuniform unstructured grids with a cell characteristic length varying in the range of 0.5–1 mm were used. In going from the 40-mm orifice to the 20-mm orifice, both the size and velocity of the vortex increase, leading to a different regime of interaction with the flame: the vortex only wrinkles the flame front in the 40-mm case (wrinkled regime) and also disrupts the continuity of the front, giving rise to the formation of separate reaction zones (i.e., flame pockets that leave the main front), in the 20-mm case (breakthrough regime). It has been found that the impact of the combustion submodel on LES predictions is strongly dependent on the regime of interaction. Results for the 40-mm orifice are substantially the same, regardless of the presence of the combustion submodel. Conversely, at the wake of the 20-mm orifice, the intensity of the flame–vortex interaction is such that the combustion submodel is strictly needed to reproduce both the qualitative (evolution of the pockets formed and their interaction with the main front) and quantitative (flame speed) characteristics of the flame propagation correctly. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202061u

Steady-state multiplicity in catalytic microcombustors / Almerinda Di Benedetto in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2130–2134 Titre : Steady-state multiplicity in catalytic microcombustors Type de document : texte imprimé Auteurs : Almerinda Di Benedetto, Auteur ; Valeria Di Sarli, Auteur Année de publication : 2010 Article en page(s) : pp. 2130–2134 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalytic  microcombustors Résumé : In this work, two-dimensional computational fluid dynamics (CFD) simulations were run to investigate the possibility of a link between the initial conditions and the occurrence of blowout for a parallel-plate catalytic microcombustor. The results show that steady-state multiplicity occurs: Depending on the initial conditions, the range of inlet gas velocities at which stable operation is attained can be enlarged to avoid blowout. It is concluded that investigations into the thermal behavior of catalytic microcombustors have to deal with appropriate and aware choices of the initial conditions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901615d [article] Steady-state multiplicity in catalytic microcombustors [texte imprimé] / Almerinda Di Benedetto, Auteur ; Valeria Di Sarli, Auteur . - 2010 . - pp. 2130–2134. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2130–2134 Mots-clés : Catalytic  microcombustors Résumé : In this work, two-dimensional computational fluid dynamics (CFD) simulations were run to investigate the possibility of a link between the initial conditions and the occurrence of blowout for a parallel-plate catalytic microcombustor. The results show that steady-state multiplicity occurs: Depending on the initial conditions, the range of inlet gas velocities at which stable operation is attained can be enlarged to avoid blowout. It is concluded that investigations into the thermal behavior of catalytic microcombustors have to deal with appropriate and aware choices of the initial conditions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901615d