Titre :
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Free convection near a stagnation point in a porous medium resulting from an oscillatory wall temperature
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Auteurs :
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J. Merkin ;
I. Pop
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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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2000
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Format :
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p. 611-621
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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 EN MILIEU POREUX
;
TEMPERATURE DE SURFACE
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Résumé :
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A detailed theoretical study of unsteady free convection boundary-layer flow near the stagnation point of a two-dimensional cylindrical surface embedded in a fluid-saturated porous medium is presented when the surface temperature oscillates about a mean value above ambient. Both numerical and asymptotic solutions are employed to solve the governing equations for general values of the frequency omega and amplitude A of the surface temperature oscillations. Results for the heat transfer rate, boundary-layer thickness and temperature profiles are obtained for both small and large Values of A and also for slow and fast oscillations. It is found that outside the thin boundary layer on the surface, a steady flow is induced for large times and fast oscillations. This steady boundary-layer flow is studied in detail for large values of the amplitude A.
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Source :
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International Journal of Heat and Mass Transfer, vol.43
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