Documents disponibles écrits par cet auteur

Comprehensive CFD Simulation of Product Yields and Coking Rates for a Floor- and Wall-Fired Naphtha Cracking Furnace / Guihua Hu in Industrial & engineering chemistry research, Vol. 50 N° 24 (Décembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13672–13685 Titre : Comprehensive CFD Simulation of Product Yields and Coking Rates for a Floor- and Wall-Fired Naphtha Cracking Furnace Type de document : texte imprimé Auteurs : Guihua Hu, Auteur ; Honggang Wang, Auteur ; Feng Qian, Auteur Année de publication : 2012 Article en page(s) : pp. 13672–13685 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Industrial  naphtha  furnace Résumé : A coupled furnace/reactor simulation was conducted to determine product yields and coking rates for an industrial SL-II naphtha cracking furnace fired by both floor and wall burners. The process gas side, as well as the fire side, is simulated using the computational fluid dynamics (CFD) approach. The molecular kinetic model of Kumar and co-workers was used to simulate the naphtha cracking reactions in the reactor. The results show that the asymmetrical design of the furnace results in asymmetrical profiles of flue gas velocity, temperature, and concentration, and leads to poor heat supply of the wall burners on the front wall as well as a high-temperature zone in the crossover section. The recirculation of flue gas caused by the positioning of burners makes the temperature more uniform in the middle of the furnace. Good agreement between simulation and industrial product yields has been obtained without any tuning of the kinetics, indicating that the proposed approach can be used as a guide for further optimization of geometries and operating parameters of naphtha cracking furnaces with burners located both in the floor and in the wall. The coking rate profile reveals that the maximum coking rate is not located at the coil outlet or near the last reactor bend, but rather at a height of 7 m in the second reactor pass. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2012642 [article] Comprehensive CFD Simulation of Product Yields and Coking Rates for a Floor- and Wall-Fired Naphtha Cracking Furnace [texte imprimé] / Guihua Hu, Auteur ; Honggang Wang, Auteur ; Feng Qian, Auteur . - 2012 . - pp. 13672–13685. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13672–13685 Mots-clés : Industrial  naphtha  furnace Résumé : A coupled furnace/reactor simulation was conducted to determine product yields and coking rates for an industrial SL-II naphtha cracking furnace fired by both floor and wall burners. The process gas side, as well as the fire side, is simulated using the computational fluid dynamics (CFD) approach. The molecular kinetic model of Kumar and co-workers was used to simulate the naphtha cracking reactions in the reactor. The results show that the asymmetrical design of the furnace results in asymmetrical profiles of flue gas velocity, temperature, and concentration, and leads to poor heat supply of the wall burners on the front wall as well as a high-temperature zone in the crossover section. The recirculation of flue gas caused by the positioning of burners makes the temperature more uniform in the middle of the furnace. Good agreement between simulation and industrial product yields has been obtained without any tuning of the kinetics, indicating that the proposed approach can be used as a guide for further optimization of geometries and operating parameters of naphtha cracking furnaces with burners located both in the floor and in the wall. The coking rate profile reveals that the maximum coking rate is not located at the coil outlet or near the last reactor bend, but rather at a height of 7 m in the second reactor pass. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2012642

Novel hybrid evolutionary algorithm for dynamic optimization problems and its application in an ethylene oxide hydration reactor / Feng Qian in Industrial & engineering chemistry research, Vol. 51 N° 49 (Décembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 15974-15985 Titre : Novel hybrid evolutionary algorithm for dynamic optimization problems and its application in an ethylene oxide hydration reactor Type de document : texte imprimé Auteurs : Feng Qian, Auteur ; Fan Sun, Auteur ; Wenli Du, Auteur Année de publication : 2013 Article en page(s) : pp. 15974-15985 Note générale : Industrial chemsitry Langues : Anglais (eng) Mots-clés : Reactor  Hydration  Optimization  Algorithm Résumé : A novel hybrid evolutionary algorithm (HEA) that combines the genetic algorithm (GA) and particle swarm optimization (PSO) is proposed to solve the dynamic optimization problems of chemical processes using numerical methods. Based on the characteristics of dynamic optimization problems, the concept of "search region reduction" is integrated into the HEA to improve the convergence rate. A control vector parametrization (CVP) method based on the HEA is also employed to improve the accuracy of the results. The dynamic optimization problem with state variable constraints is an important research area in process system engineering and is difficult to solve. Thus, the present work also proposes a novel method embedding information about infeasible chromosomes into the evaluation function to solve dynamic optimization problems with or without state variable constraints. The results of several case studies demonstrate the feasibility and efficiency of the proposed methods. Finally, the proposed methods are used to solve the temperature distribution problem in an ethylene oxide hydration reactor. Moreover, the proposed algorithm can be regarded as a useful optimization tool, especially when gradient information is unavailable. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732123 [article] Novel hybrid evolutionary algorithm for dynamic optimization problems and its application in an ethylene oxide hydration reactor [texte imprimé] / Feng Qian, Auteur ; Fan Sun, Auteur ; Wenli Du, Auteur . - 2013 . - pp. 15974-15985. Industrial chemsitry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 15974-15985 Mots-clés : Reactor  Hydration  Optimization  Algorithm Résumé : A novel hybrid evolutionary algorithm (HEA) that combines the genetic algorithm (GA) and particle swarm optimization (PSO) is proposed to solve the dynamic optimization problems of chemical processes using numerical methods. Based on the characteristics of dynamic optimization problems, the concept of "search region reduction" is integrated into the HEA to improve the convergence rate. A control vector parametrization (CVP) method based on the HEA is also employed to improve the accuracy of the results. The dynamic optimization problem with state variable constraints is an important research area in process system engineering and is difficult to solve. Thus, the present work also proposes a novel method embedding information about infeasible chromosomes into the evaluation function to solve dynamic optimization problems with or without state variable constraints. The results of several case studies demonstrate the feasibility and efficiency of the proposed methods. Finally, the proposed methods are used to solve the temperature distribution problem in an ethylene oxide hydration reactor. Moreover, the proposed algorithm can be regarded as a useful optimization tool, especially when gradient information is unavailable. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732123

A Vector-based approach for controller performance assessment / Qun Wu in Industrial & engineering chemistry research, Vol. 51 N° 48 (Décembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 48 (Décembre 2012) . - pp. 15745-15752 Titre : A Vector-based approach for controller performance assessment Type de document : texte imprimé Auteurs : Qun Wu, Auteur ; Wenli Du, Auteur ; Feng Qian, Auteur Année de publication : 2013 Article en page(s) : pp. 15745-15752 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Vector  Controller  performance Résumé : Considering that the traditional method for controller performance assessment is mainly based on minimum variance, which is an unattainable boundary, a new vector-based approach is proposed that is driven by the historical data and is not very dependent on prior knowledge of the process unit. A performance vector is designed to represent the controller precision and its response speed. The length and angle of the vector are constructed using statistical theory and signal processing techniques, which is the key step in the proposed method. It works well for disturbance rejection situation in single-input-single-output (SISO) systems. In particular, an index Pf is introduced as a measurement of the controller performance to show how much potential the control loop will still have for improvement. The Wood-Berry model is used for simulation studies to demonstrate the effectiveness of the proposed method; then, the possibility of extending the method to a multiple-input-multiple-output (MIMO) system is also discussed here. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3008105 [article] A Vector-based approach for controller performance assessment [texte imprimé] / Qun Wu, Auteur ; Wenli Du, Auteur ; Feng Qian, Auteur . - 2013 . - pp. 15745-15752. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 48 (Décembre 2012) . - pp. 15745-15752 Mots-clés : Vector  Controller  performance Résumé : Considering that the traditional method for controller performance assessment is mainly based on minimum variance, which is an unattainable boundary, a new vector-based approach is proposed that is driven by the historical data and is not very dependent on prior knowledge of the process unit. A performance vector is designed to represent the controller precision and its response speed. The length and angle of the vector are constructed using statistical theory and signal processing techniques, which is the key step in the proposed method. It works well for disturbance rejection situation in single-input-single-output (SISO) systems. In particular, an index Pf is introduced as a measurement of the controller performance to show how much potential the control loop will still have for improvement. The Wood-Berry model is used for simulation studies to demonstrate the effectiveness of the proposed method; then, the possibility of extending the method to a multiple-input-multiple-output (MIMO) system is also discussed here. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3008105