Documents disponibles écrits par cet auteur

Improved transfer coefficients for wall-flow monolithic catalytic reactors / Margaritis Kostoglou in Industrial & engineering chemistry research, Vol. 51 N° 40 (Octobre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 40 (Octobre 2012) . - pp. 13062-13072 Titre : Improved transfer coefficients for wall-flow monolithic catalytic reactors : Energy and momentum transport Type de document : texte imprimé Auteurs : Margaritis Kostoglou, Auteur ; Edward J. Bissett, Auteur ; Athanasios G. Konstandopoulos, Auteur Année de publication : 2012 Article en page(s) : pp. 13062-13072 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Transport  process  Momentum  Catalytic  reactor  Monolithic  construction Résumé : Wall-flow monolithic (WFM) catalytic reactors occupy an ever increasing important position in environmental and industrial catalysis as well as in energy applications. Their performance is very frequently determined by transport (momentum, energy, and mass) limitations, driven by the market needs for lower pressure drop, efficient heat exploitation, and miniaturization. In the present problem we address the problem of deriving the appropriate single channel equations that describe heat transfer in a wall-flow monolithic (WFM) reactor with porous channels of square-cross section. The first step of the study involves setting up a self-similar hydrodynamic problem for the two-dimensional flow field in the channel cross section. This flow field depends only on the so-called wall Reynolds number. It is shown that the self-similarity fails for large values of wall Reynolds number. The second step involves setting up the Graetz problem for the flow velocity profile found in the first step and solving for the asymptotic Nusselt number. This Nusselt number depends on the Prandtl number in addition to the wall Reynolds dependence through the flow-field. Correlations for the Nusselt number as a function of wall Reynolds and Prandtl numbers are given to facilitate the inclusion of these effects into standard practice. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26451455 [article] Improved transfer coefficients for wall-flow monolithic catalytic reactors : Energy and momentum transport [texte imprimé] / Margaritis Kostoglou, Auteur ; Edward J. Bissett, Auteur ; Athanasios G. Konstandopoulos, Auteur . - 2012 . - pp. 13062-13072. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 40 (Octobre 2012) . - pp. 13062-13072 Mots-clés : Transport  process  Momentum  Catalytic  reactor  Monolithic  construction Résumé : Wall-flow monolithic (WFM) catalytic reactors occupy an ever increasing important position in environmental and industrial catalysis as well as in energy applications. Their performance is very frequently determined by transport (momentum, energy, and mass) limitations, driven by the market needs for lower pressure drop, efficient heat exploitation, and miniaturization. In the present problem we address the problem of deriving the appropriate single channel equations that describe heat transfer in a wall-flow monolithic (WFM) reactor with porous channels of square-cross section. The first step of the study involves setting up a self-similar hydrodynamic problem for the two-dimensional flow field in the channel cross section. This flow field depends only on the so-called wall Reynolds number. It is shown that the self-similarity fails for large values of wall Reynolds number. The second step involves setting up the Graetz problem for the flow velocity profile found in the first step and solving for the asymptotic Nusselt number. This Nusselt number depends on the Prandtl number in addition to the wall Reynolds dependence through the flow-field. Correlations for the Nusselt number as a function of wall Reynolds and Prandtl numbers are given to facilitate the inclusion of these effects into standard practice. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26451455

Mathematical analysis of the meso-scale flow field in spiral-wound membrane modules / Margaritis Kostoglou in Industrial & engineering chemistry research, Vol. 50 N° 8 (Avril 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4653–4666 Titre : Mathematical analysis of the meso-scale flow field in spiral-wound membrane modules Type de document : texte imprimé Auteurs : Margaritis Kostoglou, Auteur ; Anastasios J. Karabelas, Auteur Année de publication : 2011 Article en page(s) : pp. 4653–4666 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Mathematical  analysis  Mesoscale  hydrodynamic  equations Résumé : The use of flat-sheet, spiral-wound, membrane modules for reverse osmosis and nanofiltration applications is very extensive. Design and performance optimization of these modules requires sound mathematical modeling. This study focuses on the mathematical analysis of the mesoscale hydrodynamic equations for the narrow channels with spacers, of the entire membrane sheet, previously derived from the microscale momentum conservation laws14. The mathematical problem is enhanced by considering a spatial dependence of the retentate channel and membrane permeabilities to account for fouling/scaling, aiming at future use of the proposed techniques to simulate long time fouling dynamic behavior of the process. The formal mathematical treatment of the original problem leads to several levels of approximation (depending on the problem parameter values) which admit either analytical or numerical solutions with reduced dimensionality, or numerical solutions with reduced convergence difficulties. To confirm the validity of conclusions obtained by following these procedures, several results from simplified cases are compared with numerical solutions of the original problem. Furthermore, all possible simplifications and analytical solutions of the particular problem have been obtained, as well as the conditions under which they hold, thus forming the basis for more comprehensive modeling, including mass transfer and scaling/fouling phenomena. Specific criteria are also provided for selecting appropriate simplified solutions to specific cases, helpful in the development of flow and membrane fouling simulators. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie102083j [article] Mathematical analysis of the meso-scale flow field in spiral-wound membrane modules [texte imprimé] / Margaritis Kostoglou, Auteur ; Anastasios J. Karabelas, Auteur . - 2011 . - pp. 4653–4666. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4653–4666 Mots-clés : Mathematical  analysis  Mesoscale  hydrodynamic  equations Résumé : The use of flat-sheet, spiral-wound, membrane modules for reverse osmosis and nanofiltration applications is very extensive. Design and performance optimization of these modules requires sound mathematical modeling. This study focuses on the mathematical analysis of the mesoscale hydrodynamic equations for the narrow channels with spacers, of the entire membrane sheet, previously derived from the microscale momentum conservation laws14. The mathematical problem is enhanced by considering a spatial dependence of the retentate channel and membrane permeabilities to account for fouling/scaling, aiming at future use of the proposed techniques to simulate long time fouling dynamic behavior of the process. The formal mathematical treatment of the original problem leads to several levels of approximation (depending on the problem parameter values) which admit either analytical or numerical solutions with reduced dimensionality, or numerical solutions with reduced convergence difficulties. To confirm the validity of conclusions obtained by following these procedures, several results from simplified cases are compared with numerical solutions of the original problem. Furthermore, all possible simplifications and analytical solutions of the particular problem have been obtained, as well as the conditions under which they hold, thus forming the basis for more comprehensive modeling, including mass transfer and scaling/fouling phenomena. Specific criteria are also provided for selecting appropriate simplified solutions to specific cases, helpful in the development of flow and membrane fouling simulators. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie102083j

Periodic thermal behavior of porous media under oscillating flow conditions / Margaritis Kostoglou in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 5006–5011 Titre : Periodic thermal behavior of porous media under oscillating flow conditions Type de document : texte imprimé Auteurs : Margaritis Kostoglou, Auteur Année de publication : 2010 Article en page(s) : pp. 5006–5011 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thermal  Behavior Résumé : In the present work an analytical study of the heat transfer in an oscillating flow through a porous medium is performed using a two equation model. The previous analysis performed [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085] is extended to include an arbitrary velocity magnitude and arbitrary oscillation pattern of the flow. Using asymptotic analysis with respect to several dimensionless parameters, the limits of validity of the analytical solution based on the previous approach [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085] are assessed. A new analytical solution is derived for the case of thermal equilibrium between solid and fluid. Several asymptotic results existing in the literature [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085; Klein and Eigenberger Int. J. Heat Mass Transfer 2001, 44, 3535−3563] are compared with the findings of the present work. This work completes the analytical study of the particular mathematical problem, previously advanced [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085; Klein and Eigenberger Int. J. Heat Mass Transfer 2001, 44, 3535−3563]. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014638 [article] Periodic thermal behavior of porous media under oscillating flow conditions [texte imprimé] / Margaritis Kostoglou, Auteur . - 2010 . - pp. 5006–5011. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 5006–5011 Mots-clés : Thermal  Behavior Résumé : In the present work an analytical study of the heat transfer in an oscillating flow through a porous medium is performed using a two equation model. The previous analysis performed [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085] is extended to include an arbitrary velocity magnitude and arbitrary oscillation pattern of the flow. Using asymptotic analysis with respect to several dimensionless parameters, the limits of validity of the analytical solution based on the previous approach [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085] are assessed. A new analytical solution is derived for the case of thermal equilibrium between solid and fluid. Several asymptotic results existing in the literature [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085; Klein and Eigenberger Int. J. Heat Mass Transfer 2001, 44, 3535−3563] are compared with the findings of the present work. This work completes the analytical study of the particular mathematical problem, previously advanced [Byun et al. Int. J. Heat Mass Transfer 2006, 49, 5081−5085; Klein and Eigenberger Int. J. Heat Mass Transfer 2001, 44, 3535−3563]. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014638