Documents disponibles écrits par cet auteur

Coordination number of the packing of ternary mixtures of spheres / L. Y. Yi in Industrial & engineering chemistry research, Vol. 50 N° 14 (Juillet 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 14 (Juillet 2011) . - pp. 8773-8785 Titre : Coordination number of the packing of ternary mixtures of spheres : DEM simulations versus measurements Type de document : texte imprimé Auteurs : L. Y. Yi, Auteur ; K. J. Dong, Auteur ; R. P. Zou, Auteur Année de publication : 2011 Article en page(s) : pp. 8773-8785 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Ternary  mixture Résumé : Coordination number is an important microscopic parameter in describing the packing of particles. However, little information is available for particle mixtures because of the difficulty of investigating them experimentally. This article presents a numerical study on the coordination numbers of a ternary packing system with size ratios of 24.4/11.6/6.4 by means of the discrete element method (DEM). Good agreement between the simulated and measured results was obtained, which confirms, at a particle scale, that DEM is capable of generating reliable results for structural analysis of particle packing. It was also found that the coordination number distribution of each of the cases considered can be described by the so-called Johnson SB function. The distribution parameters of the function were quantified based on the DEM simulation results so that the coordination number distributions corresponding to different contact types in this ternary packing system can be fully described. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24346918 [article] Coordination number of the packing of ternary mixtures of spheres : DEM simulations versus measurements [texte imprimé] / L. Y. Yi, Auteur ; K. J. Dong, Auteur ; R. P. Zou, Auteur . - 2011 . - pp. 8773-8785. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 14 (Juillet 2011) . - pp. 8773-8785 Mots-clés : Ternary  mixture Résumé : Coordination number is an important microscopic parameter in describing the packing of particles. However, little information is available for particle mixtures because of the difficulty of investigating them experimentally. This article presents a numerical study on the coordination numbers of a ternary packing system with size ratios of 24.4/11.6/6.4 by means of the discrete element method (DEM). Good agreement between the simulated and measured results was obtained, which confirms, at a particle scale, that DEM is capable of generating reliable results for structural analysis of particle packing. It was also found that the coordination number distribution of each of the cases considered can be described by the so-called Johnson SB function. The distribution parameters of the function were quantified based on the DEM simulation results so that the coordination number distributions corresponding to different contact types in this ternary packing system can be fully described. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24346918

DEM simulation of cake formation in sedimentation and filtration / K. J. Dong in Minerals engineering, Vol. 22 N° 11 (Octobre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 11 (Octobre 2009) . - pp. 921–930 Titre : DEM simulation of cake formation in sedimentation and filtration Type de document : texte imprimé Auteurs : K. J. Dong, Auteur ; R. P. Zou, Auteur ; R.Y. Yang, Auteur Année de publication : 2009 Article en page(s) : pp. 921–930 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Liquid–solid  separation  Sedimentation  Filtration  Particle  packing  Discrete  element  method Résumé : This paper presents a DEM study of cake formation and growth in sedimentation and filtration processes with constant flow rate or pressure. The liquid flow is assumed to be one-dimensional and the motion of particles is three-dimensional. Various forces are included to determine the motion of particles, including the particle–particle contact forces, the van der Waals force and the particle–fluid interactions such as buoyancy, drag and lift forces. The effects of the material properties of particles and liquid and the operational conditions are examined. The structures of cakes are also analysed and the relationship between cake porosity and interparticle force is quantified. The microscopic analysis demonstrates that these variables affect the process and the cake structures through their effects on the gravity or cohesive force, which competes in controlling the formation of a cake. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001010 [article] DEM simulation of cake formation in sedimentation and filtration [texte imprimé] / K. J. Dong, Auteur ; R. P. Zou, Auteur ; R.Y. Yang, Auteur . - 2009 . - pp. 921–930. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 11 (Octobre 2009) . - pp. 921–930 Mots-clés : Liquid–solid  separation  Sedimentation  Filtration  Particle  packing  Discrete  element  method Résumé : This paper presents a DEM study of cake formation and growth in sedimentation and filtration processes with constant flow rate or pressure. The liquid flow is assumed to be one-dimensional and the motion of particles is three-dimensional. Various forces are included to determine the motion of particles, including the particle–particle contact forces, the van der Waals force and the particle–fluid interactions such as buoyancy, drag and lift forces. The effects of the material properties of particles and liquid and the operational conditions are examined. The structures of cakes are also analysed and the relationship between cake porosity and interparticle force is quantified. The microscopic analysis demonstrates that these variables affect the process and the cake structures through their effects on the gravity or cohesive force, which competes in controlling the formation of a cake. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001010

DEM simulation of particle flow on a multi-deck banana screen / K. J. Dong in Minerals engineering, Vol. 22 N° 11 (Octobre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 11 (Octobre 2009) . - pp. 910–920 Titre : DEM simulation of particle flow on a multi-deck banana screen Type de document : texte imprimé Auteurs : K. J. Dong, Auteur ; A. B. Yu, Auteur ; I. Brake, Auteur Année de publication : 2009 Article en page(s) : pp. 910–920 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Screening  Coal  preparation  Discrete  Element  Method  Process  simulation Résumé : Banana screen is an important innovation in screening process in the past decades to improve screen capacity. Although, it is increasingly employed in the mineral industry, the control and optimisation are still limited due to the lack of fundamental understandings of the process. This paper presents a numerical study of the particle flow on a banana screen at a particle scale by means of Discrete Element Method (DEM). Typical 3-deck and 5-deck banana screens are simulated. The effects of operational conditions and geometry on the screen performance are studied by a series of controlled numerical experiments. The results are analysed in terms of partition curves, distributions of percentage passing and other flow information, such as particle volume and velocities along the screen deck. They are useful to the development of a better understanding and the control of banana screening processes. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001046 [article] DEM simulation of particle flow on a multi-deck banana screen [texte imprimé] / K. J. Dong, Auteur ; A. B. Yu, Auteur ; I. Brake, Auteur . - 2009 . - pp. 910–920. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 11 (Octobre 2009) . - pp. 910–920 Mots-clés : Screening  Coal  preparation  Discrete  Element  Method  Process  simulation Résumé : Banana screen is an important innovation in screening process in the past decades to improve screen capacity. Although, it is increasingly employed in the mineral industry, the control and optimisation are still limited due to the lack of fundamental understandings of the process. This paper presents a numerical study of the particle flow on a banana screen at a particle scale by means of Discrete Element Method (DEM). Typical 3-deck and 5-deck banana screens are simulated. The effects of operational conditions and geometry on the screen performance are studied by a series of controlled numerical experiments. The results are analysed in terms of partition curves, distributions of percentage passing and other flow information, such as particle volume and velocities along the screen deck. They are useful to the development of a better understanding and the control of banana screening processes. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001046

A numerical model for the liquid flow in a sputnik coal distributor / B.Y. Guo in Minerals engineering, Vol. 22 N° 1 (Janvier 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 1 (Janvier 2009) . - pp. 78–87 Titre : A numerical model for the liquid flow in a sputnik coal distributor Type de document : texte imprimé Auteurs : B.Y. Guo, Auteur ; K. J. Dong, Auteur ; K. W. Chu, Auteur Année de publication : 2009 Article en page(s) : pp. 78–87 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Coal  preparation  Coal  distributor  Fluid  flow  Numerical  modeling  Computational  fluid  dynamics Index. décimale : 622 Industrie minière Résumé : Sputnik coal distributors are widely applied in coal separation plants and biased outputs are frequently encountered. The present paper aims to develop a numerical model for simulating the flow of the carrier liquid within a distributor chamber. The model uses simple homogeneous multi-phase flow model and performs well in terms of successfully predicting the important phenomena within the distributor chamber, such as the strong vortex in the upper chamber and channeling through the slots on the orifice plate, as observed experimentally. The model provides necessary information for particle flow modeling and offers a useful tool to trouble-shooting of operations and optimization of design for such type of devices. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687508001088 [article] A numerical model for the liquid flow in a sputnik coal distributor [texte imprimé] / B.Y. Guo, Auteur ; K. J. Dong, Auteur ; K. W. Chu, Auteur . - 2009 . - pp. 78–87. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 1 (Janvier 2009) . - pp. 78–87 Mots-clés : Coal  preparation  Coal  distributor  Fluid  flow  Numerical  modeling  Computational  fluid  dynamics Index. décimale : 622 Industrie minière Résumé : Sputnik coal distributors are widely applied in coal separation plants and biased outputs are frequently encountered. The present paper aims to develop a numerical model for simulating the flow of the carrier liquid within a distributor chamber. The model uses simple homogeneous multi-phase flow model and performs well in terms of successfully predicting the important phenomena within the distributor chamber, such as the strong vortex in the upper chamber and channeling through the slots on the orifice plate, as observed experimentally. The model provides necessary information for particle flow modeling and offers a useful tool to trouble-shooting of operations and optimization of design for such type of devices. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687508001088

Numerical simulation of the in-line pressure jig unit in coal preparation / K. J. Dong in Minerals engineering, Vol. 23 N° 4 (Mars 2010) 

Public ISBD [article]  in Minerals engineering > Vol. 23 N° 4 (Mars 2010) . - pp. 301–312 Titre : Numerical simulation of the in-line pressure jig unit in coal preparation Type de document : texte imprimé Auteurs : K. J. Dong, Auteur ; S. B. Kuang, Auteur ; A. Vince, Auteur Année de publication : 2011 Article en page(s) : pp. 301–312 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Gravity  concentration  Classification  Coal  Computational  fluid  dynamics  Discrete  element  method Résumé : This paper presents a numerical study of the multiphase flow in an in-line pressure jig (IPJ), which is a high yield and high recovery gravity separation device widely used in ore processing but may have potential in coal preparation. The mathematical model is developed by use of the combined approach of computational fluid dynamics (CFD) for liquid flow and discrete element method (DEM) for particle flow. It is qualitatively verified by comparing the calculated and measured results under similar conditions. The effects of a few key variables, such as vibration frequency and amplitude, and the size and density of ragging particles, on the flow and separation performance of the IPJ are studied by conducting a series of simulations. The results are analyzed in terms of velocity field, porosity distribution and forces on particles. The findings would be helpful in the design, control and optimisation of an IPJ unit. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509002635 [article] Numerical simulation of the in-line pressure jig unit in coal preparation [texte imprimé] / K. J. Dong, Auteur ; S. B. Kuang, Auteur ; A. Vince, Auteur . - 2011 . - pp. 301–312. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 23 N° 4 (Mars 2010) . - pp. 301–312 Mots-clés : Gravity  concentration  Classification  Coal  Computational  fluid  dynamics  Discrete  element  method Résumé : This paper presents a numerical study of the multiphase flow in an in-line pressure jig (IPJ), which is a high yield and high recovery gravity separation device widely used in ore processing but may have potential in coal preparation. The mathematical model is developed by use of the combined approach of computational fluid dynamics (CFD) for liquid flow and discrete element method (DEM) for particle flow. It is qualitatively verified by comparing the calculated and measured results under similar conditions. The effects of a few key variables, such as vibration frequency and amplitude, and the size and density of ragging particles, on the flow and separation performance of the IPJ are studied by conducting a series of simulations. The results are analyzed in terms of velocity field, porosity distribution and forces on particles. The findings would be helpful in the design, control and optimisation of an IPJ unit. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509002635