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Experimental and computational investigation of two phase gas — liquid flows / Ashraf Ali in Industrial & engineering chemistry research, Vol. 50 N° 23 (Décembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 23 (Décembre 2011) . - pp. 13220-13229 Titre : Experimental and computational investigation of two phase gas — liquid flows : point source injection at the center Type de document : texte imprimé Auteurs : Ashraf Ali, Auteur ; S. Pushpavanam, Auteur Année de publication : 2012 Article en page(s) : pp. 13220-13229 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Point  source  Two  phase  flow  Gas  liquid  flow Résumé : In this work, an experimental and numerical investigation ofhydrodynamics in a liquid induced by a bubble plume is carried out. The gas is introduced through a needle in the center of the tank containing water. The gas―liquid flow in such systems is inherently unsteady. Particle image velocimetry (PIV) was used to experimentally determine the transient velocity fields in the system. For this gas―liquid flow system, both the fluctuating and mean liquid velocities were determined experimentally by 2D and 3D PIV. The system was investigated for a liquid phase Reynolds number in the range of 3.7 × 104 to 1.8 × 105 and bubble phase Reynolds number in the range from 2350 to 11773. The behavior of the system was simulated in FLUENT 6.3.26 using a two fluid Euler―Lagrangian (EL) model with a constant bubble size of 5 mm. Here, water is treated as the continuous phase, and gas bubbles are treated as the dispersed phase. Motion of the bubbles renders the flow turbulent, and this effect is captured by the standard k―ε turbulence model. The temporal prediction of the flow field is compared with experimental results obtained from 2D and 3D measurements. The predictions from the 3D simulations capture the oscillating behavior found using 3D PIV. The 2D simulations predict a significantly higher value of turbulent viscosity. This is hypothesized as the reason as to why these simulations do not capture the oscillating behavior. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25267477 [article] Experimental and computational investigation of two phase gas — liquid flows : point source injection at the center [texte imprimé] / Ashraf Ali, Auteur ; S. Pushpavanam, Auteur . - 2012 . - pp. 13220-13229. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 23 (Décembre 2011) . - pp. 13220-13229 Mots-clés : Point  source  Two  phase  flow  Gas  liquid  flow Résumé : In this work, an experimental and numerical investigation ofhydrodynamics in a liquid induced by a bubble plume is carried out. The gas is introduced through a needle in the center of the tank containing water. The gas―liquid flow in such systems is inherently unsteady. Particle image velocimetry (PIV) was used to experimentally determine the transient velocity fields in the system. For this gas―liquid flow system, both the fluctuating and mean liquid velocities were determined experimentally by 2D and 3D PIV. The system was investigated for a liquid phase Reynolds number in the range of 3.7 × 104 to 1.8 × 105 and bubble phase Reynolds number in the range from 2350 to 11773. The behavior of the system was simulated in FLUENT 6.3.26 using a two fluid Euler―Lagrangian (EL) model with a constant bubble size of 5 mm. Here, water is treated as the continuous phase, and gas bubbles are treated as the dispersed phase. Motion of the bubbles renders the flow turbulent, and this effect is captured by the standard k―ε turbulence model. The temporal prediction of the flow field is compared with experimental results obtained from 2D and 3D measurements. The predictions from the 3D simulations capture the oscillating behavior found using 3D PIV. The 2D simulations predict a significantly higher value of turbulent viscosity. This is hypothesized as the reason as to why these simulations do not capture the oscillating behavior. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25267477