Titre :
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Comparison of linear and nonlinear RNG-based k-epsilon models for incompressible turbulent flows
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Auteurs :
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G. Papageorgakis ;
D. Assanis
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Type de document :
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article/chapitre/communication
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Année de publication :
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1999
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Format :
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p. 1-22
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Langues:
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= Anglais
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Catégories :
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THERMIQUE THERMODYNAMIQUE
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Mots-clés:
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ECOULEMENT TURBULENT
;
MODELE
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Résumé :
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Linear and nonlinear renormalization group (RNG) - models are compared for the prediction of incompressible turbulent flows. The multidimensional finite-volume code KIVA-3 is used to explore the alternative models versus the standard - model. Test cases include the classic backward-facing step and the confined co-flow jet flows. Our results suggest that the linear RNG - model can yield significant improvements over the standard - model for recirculatory flows, because of its less dissipative nature. While the nonlinear RNG - model can also improve predictions compared to the standard - model, its greatly increased cost compared to the linear RNG model renders it less attractive. However, for the case of shear flows, such as for confined co-flow jets, the RNG-based - models are in less favorable agreement with experiments compared to the standard - model. Overall, it is concluded that combining the claimed universality of the RNG-based - model constants with the anisotropies introduced by the nonlinear - model cannot enhance predictions of both recirculating and shear incompressible flows.
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Source :
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Numerical heat transfer. Part B fundamentals, vol.35, n°1
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