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Particle trajectory study in submerged flows with baffles using ν2¯−f and k−ε turbulence models / A. Mehdizadeh in Transactions of the ASME . Journal of fluids engineering, Vol. 132 N° 5 (Mai 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of fluids engineering > Vol. 132 N° 5 (Mai 2010) . - 10 p. Titre : Particle trajectory study in submerged flows with baffles using ν2¯−f and k−ε turbulence models Type de document : texte imprimé Auteurs : A. Mehdizadeh, Auteur ; B. Firoozabadi, Auteur ; S. A. Sherif, Auteur Année de publication : 2010 Article en page(s) : 10 p. Note générale : fluids engineering Langues : Anglais (eng) Mots-clés : flow  (dynamics);  particulate  matter;  turbulence;  trajectories  (physics);  erosion;  equations Résumé : In this paper, the structure of a wall jet deflected by a baffle along with the trajectory of particles has been studied. This baffle is used to produce a stable deflected surface jet, thereby deflecting the high-velocity supercritical stream away from the bed to the surface. An elliptic relaxation turbulence model (ν2¯−f model) has been used to simulate this submerged flow. In recent years, the ν2¯−f turbulence model has become increasingly popular due to its ability to account for near-wall damping without use of damping functions. In addition, it has been proven that the ν2¯−f model is superior to other Reynolds-averaged Navier-Stokes (RANS) methods in many flows where complex flow features are present. In this study, we compare the results of the ν2¯−f model with available experimental data. Since erosion and deposition are coupled, the study of this problem should consider both of these phenomena using a proper approach. In addition to erosion over the bed, the trajectory of the particles is examined using a Lagrangian–Eulerian approach, the distribution of deposited particles over the bed is predicted for a two-phase test case based on a series of numerical simulations. Results show that the maximum erosion happens in a place in which no particle can be deposited, which causes the bed to deform very rapidly in that region. This should help prevent or reduce erosion over the bed. On the other hand, the study will help predict the trajectory of particles and the deposition rates at any section of the channel, and should thus provide useful information to control the erosion and deposition on the channel bed. DEWEY : 620.1 ISSN : 0098-2202 En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/Issue.aspx?issueID=27418 [...] [article] Particle trajectory study in submerged flows with baffles using ν2¯−f and k−ε turbulence models [texte imprimé] / A. Mehdizadeh, Auteur ; B. Firoozabadi, Auteur ; S. A. Sherif, Auteur . - 2010 . - 10 p. fluids engineering Langues : Anglais (eng) in Transactions of the ASME . Journal of fluids engineering > Vol. 132 N° 5 (Mai 2010) . - 10 p. Mots-clés : flow  (dynamics);  particulate  matter;  turbulence;  trajectories  (physics);  erosion;  equations Résumé : In this paper, the structure of a wall jet deflected by a baffle along with the trajectory of particles has been studied. This baffle is used to produce a stable deflected surface jet, thereby deflecting the high-velocity supercritical stream away from the bed to the surface. An elliptic relaxation turbulence model (ν2¯−f model) has been used to simulate this submerged flow. In recent years, the ν2¯−f turbulence model has become increasingly popular due to its ability to account for near-wall damping without use of damping functions. In addition, it has been proven that the ν2¯−f model is superior to other Reynolds-averaged Navier-Stokes (RANS) methods in many flows where complex flow features are present. In this study, we compare the results of the ν2¯−f model with available experimental data. Since erosion and deposition are coupled, the study of this problem should consider both of these phenomena using a proper approach. In addition to erosion over the bed, the trajectory of the particles is examined using a Lagrangian–Eulerian approach, the distribution of deposited particles over the bed is predicted for a two-phase test case based on a series of numerical simulations. Results show that the maximum erosion happens in a place in which no particle can be deposited, which causes the bed to deform very rapidly in that region. This should help prevent or reduce erosion over the bed. On the other hand, the study will help predict the trajectory of particles and the deposition rates at any section of the channel, and should thus provide useful information to control the erosion and deposition on the channel bed. DEWEY : 620.1 ISSN : 0098-2202 En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/Issue.aspx?issueID=27418 [...]