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Liquid-Phase Residence Time Distribution for Two-Phase Flow in Coiled Flow Inverter / Subhashini Vashisth in Industrial & engineering chemistry research, Vol. 47 N°10 (Mai 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3630–3638 Titre : Liquid-Phase Residence Time Distribution for Two-Phase Flow in Coiled Flow Inverter Type de document : texte imprimé Auteurs : Subhashini Vashisth, Auteur ; K. D. P. Nigam, Auteur Année de publication : 2008 Article en page(s) : p. 3630–3638 Langues : Anglais (eng) Mots-clés : The  coiled  flow  inverter  --  Liquid-phase  residence  time  distribution(RTD)  ;  Gas  -liquid  ;  newtonian  fluids Résumé : The coiled flow inverter (CFI) is an innovative device, which has potential for the intensification of processes currently carried out in conventional mixers. Step response experiments were carried out in a CFI to study liquid-phase residence time distribution (RTD) for gas−liquid flow under the conditions of both negligible and significant molecular diffusion using Newtonian fluids. A total of 16 CFIs of different curvature ratios ranging from 6.7 to 20, dimensionless pitch from 1 to 2.5, and number of bends from 1 to 15 were investigated. The range of Dean numbers for the gas and the liquid phase was varied from 235 to 1180 and 3.16 to 1075, respectively. The reduction in dispersion number is nearly 2.6 times for two-phase flow in CFI with 15 number of bends as compared to a straight helix under identical process conditions. A modified axial dispersion model is proposed to describe the RTD. The efficiency of the device is characterized by a mixing criterion. En ligne : https://pubs.acs.org/doi/abs/10.1021/ie070447h [article] Liquid-Phase Residence Time Distribution for Two-Phase Flow in Coiled Flow Inverter [texte imprimé] / Subhashini Vashisth, Auteur ; K. D. P. Nigam, Auteur . - 2008 . - p. 3630–3638. Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3630–3638 Mots-clés : The  coiled  flow  inverter  --  Liquid-phase  residence  time  distribution(RTD)  ;  Gas  -liquid  ;  newtonian  fluids Résumé : The coiled flow inverter (CFI) is an innovative device, which has potential for the intensification of processes currently carried out in conventional mixers. Step response experiments were carried out in a CFI to study liquid-phase residence time distribution (RTD) for gas−liquid flow under the conditions of both negligible and significant molecular diffusion using Newtonian fluids. A total of 16 CFIs of different curvature ratios ranging from 6.7 to 20, dimensionless pitch from 1 to 2.5, and number of bends from 1 to 15 were investigated. The range of Dean numbers for the gas and the liquid phase was varied from 235 to 1180 and 3.16 to 1075, respectively. The reduction in dispersion number is nearly 2.6 times for two-phase flow in CFI with 15 number of bends as compared to a straight helix under identical process conditions. A modified axial dispersion model is proposed to describe the RTD. The efficiency of the device is characterized by a mixing criterion. En ligne : https://pubs.acs.org/doi/abs/10.1021/ie070447h

A review on the potential applications of curved geometries in process industry / Subhashini Vashisth in Industrial & engineering chemistry research, Vol. 47 N°10 (Mai 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3291–3337 Titre : A review on the potential applications of curved geometries in process industry Type de document : texte imprimé Auteurs : Subhashini Vashisth, Auteur ; Vimal Kumar, Auteur ; Krishna D. P. Nigam, Auteur Année de publication : 2008 Article en page(s) : p. 3291–3337 Note générale : Bibliogr. p. 3327-3337 Langues : Anglais (eng) Mots-clés : Curved  tubes;  Friction  factor;  Heat  transfer;  Mass  transfer Résumé : The potential industrial applications of curved tubes for single- and two-phase flow are reviewed within the context of physics of flow, trends in the development of technology, and its laboratory to industrial-scale commercialization. Comparison of the performance of curved tube configurations demonstrates its edge over the conventional motionless mixers, heat exchangers, and reactors. Alongside, their respective advantages and limitations are also highlighted. Further, a compendium of the available correlations for single- and two-phase friction factor and heat- and mass-transfer coefficient in curved tubes has also been presented. Key issues regarding the design parameters governing the performance of the curved tubes for mixing and heat- and mass-transfer that impact the research, development, and scale-up or scale-down of such devices are also analyzed. Emerging trends for the development of a new class of curved tubes, namely, inverters and serpentine and chaotic devices are also presented. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701760h [article] A review on the potential applications of curved geometries in process industry [texte imprimé] / Subhashini Vashisth, Auteur ; Vimal Kumar, Auteur ; Krishna D. P. Nigam, Auteur . - 2008 . - p. 3291–3337. Bibliogr. p. 3327-3337 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3291–3337 Mots-clés : Curved  tubes;  Friction  factor;  Heat  transfer;  Mass  transfer Résumé : The potential industrial applications of curved tubes for single- and two-phase flow are reviewed within the context of physics of flow, trends in the development of technology, and its laboratory to industrial-scale commercialization. Comparison of the performance of curved tube configurations demonstrates its edge over the conventional motionless mixers, heat exchangers, and reactors. Alongside, their respective advantages and limitations are also highlighted. Further, a compendium of the available correlations for single- and two-phase friction factor and heat- and mass-transfer coefficient in curved tubes has also been presented. Key issues regarding the design parameters governing the performance of the curved tubes for mixing and heat- and mass-transfer that impact the research, development, and scale-up or scale-down of such devices are also analyzed. Emerging trends for the development of a new class of curved tubes, namely, inverters and serpentine and chaotic devices are also presented. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701760h