Documents disponibles écrits par cet auteur

Cavitating turbulent flow simulation in a Francis turbine based on mixture model / Shuhong Liu in Transactions of the ASME . Journal of fluids engineering, Vol. 131 N° 5 (Mai 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of fluids engineering > Vol. 131 N° 5 (Mai 2009) . - 08 p. Titre : Cavitating turbulent flow simulation in a Francis turbine based on mixture model Type de document : texte imprimé Auteurs : Shuhong Liu, Auteur ; Liang Zhang, Auteur ; Michihiro Nishi, Auteur Année de publication : 2009 Article en page(s) : 08 p. Note générale : fluids engineering Langues : Anglais (eng) Mots-clés : Francis  turbine;  cavitation  performance;  mixture  model;  direct  coupling  numerical  technique Résumé : As a numerical method to study the cavitation performance of a Francis turbine, the mixture model for the cavity/liquid two-phase flow is adopted in the cavitating turbulent flow analysis together with the re-normalization group (RNG) k-ε turbulence model in the present paper. The direct coupling numerical technique is used to solve the governing equations of the mixture model for the two-phase flow. Unsteady cavitating flow simulation around a hydrofoil of ALE15 is conducted as preliminary evaluation. Then, the cavitating flow in a Francis turbine is treated from the steady flow simulation since the feasibility of the cavitation model to the performance prediction of the turbine is the present major concern. Comparisons of the computational results with the model test data, i.e., the cavitation characteristics of hydraulic efficiency and the overload vortex rope at the draft tube inlet being reproduced reasonably, indicate that the present method has sufficient potential to simulate the cavitating flow in hydraulic turbines. Further, the unsteady cavitating flow simulation through the Francis turbine is conducted as well to study the pressure fluctuation characters caused by the vortex rope in the draft tube at partial load operation. En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...] [article] Cavitating turbulent flow simulation in a Francis turbine based on mixture model [texte imprimé] / Shuhong Liu, Auteur ; Liang Zhang, Auteur ; Michihiro Nishi, Auteur . - 2009 . - 08 p. fluids engineering Langues : Anglais (eng) in Transactions of the ASME . Journal of fluids engineering > Vol. 131 N° 5 (Mai 2009) . - 08 p. Mots-clés : Francis  turbine;  cavitation  performance;  mixture  model;  direct  coupling  numerical  technique Résumé : As a numerical method to study the cavitation performance of a Francis turbine, the mixture model for the cavity/liquid two-phase flow is adopted in the cavitating turbulent flow analysis together with the re-normalization group (RNG) k-ε turbulence model in the present paper. The direct coupling numerical technique is used to solve the governing equations of the mixture model for the two-phase flow. Unsteady cavitating flow simulation around a hydrofoil of ALE15 is conducted as preliminary evaluation. Then, the cavitating flow in a Francis turbine is treated from the steady flow simulation since the feasibility of the cavitation model to the performance prediction of the turbine is the present major concern. Comparisons of the computational results with the model test data, i.e., the cavitation characteristics of hydraulic efficiency and the overload vortex rope at the draft tube inlet being reproduced reasonably, indicate that the present method has sufficient potential to simulate the cavitating flow in hydraulic turbines. Further, the unsteady cavitating flow simulation through the Francis turbine is conducted as well to study the pressure fluctuation characters caused by the vortex rope in the draft tube at partial load operation. En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...]

Hg removal characteristics of noncarbon sorbents in a fixed - bed reactor / Liang Zhang in Industrial & engineering chemistry research, Vol. 51 N° 14 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5292-5298 Titre : Hg removal characteristics of noncarbon sorbents in a fixed - bed reactor Type de document : texte imprimé Auteurs : Liang Zhang, Auteur ; Yuqun Zhuo, Auteur ; Wen Du, Auteur Année de publication : 2012 Article en page(s) : pp. 5292-5298 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Fixed  bed  reactor Résumé : This research targeted the development of a low-cost, high-effidenry sorbent for mercury capture in flue gas. Six non-carbon-based carriers and various impregnating substances including Nal, CuCl2, CuBr, and FeCl3 were investigated in this study. The performances of the prepared sorbents were tested in a bench-scale fixed-bed reactor at 140 °C in N2 atmosphere. Some sorbents demonstrated the mercury capture capabilities similar to that of a commercial active carbon sorbent (Norit Darco LH). ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25783438 [article] Hg removal characteristics of noncarbon sorbents in a fixed - bed reactor [texte imprimé] / Liang Zhang, Auteur ; Yuqun Zhuo, Auteur ; Wen Du, Auteur . - 2012 . - pp. 5292-5298. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5292-5298 Mots-clés : Fixed  bed  reactor Résumé : This research targeted the development of a low-cost, high-effidenry sorbent for mercury capture in flue gas. Six non-carbon-based carriers and various impregnating substances including Nal, CuCl2, CuBr, and FeCl3 were investigated in this study. The performances of the prepared sorbents were tested in a bench-scale fixed-bed reactor at 140 °C in N2 atmosphere. Some sorbents demonstrated the mercury capture capabilities similar to that of a commercial active carbon sorbent (Norit Darco LH). ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25783438

Influences of pressure on the operation of reactive distillation columns involving kinetically controlled exothermic reactions / Chao Wang in Industrial & engineering chemistry research, Vol. 51 N° 9 (Mars 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 9 (Mars 2012) . - pp. 3692-3708 Titre : Influences of pressure on the operation of reactive distillation columns involving kinetically controlled exothermic reactions Type de document : texte imprimé Auteurs : Chao Wang, Auteur ; Liang Zhang, Auteur ; Kejin Huang, Auteur Année de publication : 2012 Article en page(s) : pp. 3692-3708 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Exothermic  reaction  Distillation  column  Distillation  with  reaction Résumé : For the reactive distillation column involving a kinetically controlled exothermic reaction, operating pressure can present nonmonotonic influences on process dynamics and operation. While the enhancement of operating pressure benefits process dynamics and controllability in the lower part of its feasible region (which is confined by the temperature levels of the available cold and hot utilities), it turns to deteriorate process dynamics and controllability in the higher part of its feasible region. Three reactive distillation systems, including an ideal reactive distillation column performing a hypothetical exothermic reaction, A + Bkf⇄ kb C + D, and two real ones producing, respectively, methyl acetate from acetic acid and methanol and methyl tertiary butyl ether (MTBE) from isobutylene and methanol, are thoroughly studied in this work, and the results confirm the existence of this unique phenomenon. The intricate behavior of such kind of reactive distillation columns is essentially governed by the conflicting effects of operating pressure on reaction rate and chemical equilibrium constant and determines actually a favorable region of operating pressure for process dynamics and operation. Because the region may or may not coincide with the one in terms of process synthesis and design, operating pressure can therefore serve as an important decision variable to trade-off process design and operation, rendering the resultant process design with balanced steady-state performance and process dynamics and controllability. ISSN : 0888 -5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25595798 [article] Influences of pressure on the operation of reactive distillation columns involving kinetically controlled exothermic reactions [texte imprimé] / Chao Wang, Auteur ; Liang Zhang, Auteur ; Kejin Huang, Auteur . - 2012 . - pp. 3692-3708. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 9 (Mars 2012) . - pp. 3692-3708 Mots-clés : Exothermic  reaction  Distillation  column  Distillation  with  reaction Résumé : For the reactive distillation column involving a kinetically controlled exothermic reaction, operating pressure can present nonmonotonic influences on process dynamics and operation. While the enhancement of operating pressure benefits process dynamics and controllability in the lower part of its feasible region (which is confined by the temperature levels of the available cold and hot utilities), it turns to deteriorate process dynamics and controllability in the higher part of its feasible region. Three reactive distillation systems, including an ideal reactive distillation column performing a hypothetical exothermic reaction, A + Bkf⇄ kb C + D, and two real ones producing, respectively, methyl acetate from acetic acid and methanol and methyl tertiary butyl ether (MTBE) from isobutylene and methanol, are thoroughly studied in this work, and the results confirm the existence of this unique phenomenon. The intricate behavior of such kind of reactive distillation columns is essentially governed by the conflicting effects of operating pressure on reaction rate and chemical equilibrium constant and determines actually a favorable region of operating pressure for process dynamics and operation. Because the region may or may not coincide with the one in terms of process synthesis and design, operating pressure can therefore serve as an important decision variable to trade-off process design and operation, rendering the resultant process design with balanced steady-state performance and process dynamics and controllability. ISSN : 0888 -5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25595798

Reactive distillation columns with a top-bottom external recycle / Haisheng Chen in Industrial & engineering chemistry research, Vol. 51 N° 44 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 44 (Novembre 2012) . - pp. 14473-14488 Titre : Reactive distillation columns with a top-bottom external recycle Type de document : texte imprimé Auteurs : Haisheng Chen, Auteur ; Kejin Huang, Auteur ; Liang Zhang, Auteur Année de publication : 2013 Article en page(s) : pp. 14473-14488 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Distillation  column  Distillation  with  reaction Résumé : Although reactive distillation columns represent a promising technology for process intensification between reaction operation and separation operation, it is difficult to use for the separation of reacting mixtures with the most and the least volatile reactants (i.e., the most unfavorable ranking of relative volatilities). To overcome the difficulty, we propose two novel configurations featured a top-bottom external recycle for the separation of exothermic and endothermic reactions, respectively. While the external recycle should be directed from the top to the bottom for the exothermic reactions, it should be from the bottom to the top for the endothermic reactions. With the arrangement of a reactive section at the bottom for the exothermic reactions and at the top for the endothermic reactions, the two process configurations proposed favor considerably internal mass integration and internal energy integration between the reaction operation and the separation operation involved and help, consequently, to enhance the thermodynamic efficiencies of the reactive distillation columns. A simple and effective procedure for process synthesis and design is devised, and four examples, including an ideal quaternary exothermic reaction, an ideal quaternary endothermic one, the esterification of latic acid with methanol, and the esterification of palmitic acid with isopropanol, are chosen to evaluate the two configurations proposed. The obtained results show that they are definitely superior to those with two or one reactive sections at both or either ends in the aspect of capital investment and operating cost They are also demonstrated to be highly competitive alternatives to the conventional reactor/separator/recycle systems. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26620361 [article] Reactive distillation columns with a top-bottom external recycle [texte imprimé] / Haisheng Chen, Auteur ; Kejin Huang, Auteur ; Liang Zhang, Auteur . - 2013 . - pp. 14473-14488. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 44 (Novembre 2012) . - pp. 14473-14488 Mots-clés : Distillation  column  Distillation  with  reaction Résumé : Although reactive distillation columns represent a promising technology for process intensification between reaction operation and separation operation, it is difficult to use for the separation of reacting mixtures with the most and the least volatile reactants (i.e., the most unfavorable ranking of relative volatilities). To overcome the difficulty, we propose two novel configurations featured a top-bottom external recycle for the separation of exothermic and endothermic reactions, respectively. While the external recycle should be directed from the top to the bottom for the exothermic reactions, it should be from the bottom to the top for the endothermic reactions. With the arrangement of a reactive section at the bottom for the exothermic reactions and at the top for the endothermic reactions, the two process configurations proposed favor considerably internal mass integration and internal energy integration between the reaction operation and the separation operation involved and help, consequently, to enhance the thermodynamic efficiencies of the reactive distillation columns. A simple and effective procedure for process synthesis and design is devised, and four examples, including an ideal quaternary exothermic reaction, an ideal quaternary endothermic one, the esterification of latic acid with methanol, and the esterification of palmitic acid with isopropanol, are chosen to evaluate the two configurations proposed. The obtained results show that they are definitely superior to those with two or one reactive sections at both or either ends in the aspect of capital investment and operating cost They are also demonstrated to be highly competitive alternatives to the conventional reactor/separator/recycle systems. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26620361