Documents disponibles écrits par cet auteur

Forced convection in a channel partly occupied by a bidisperse porous medium / D. A. Nield in Journal of heat transfer, Vol. 133 N° 7 (Juillet 2011) 

Public ISBD [article]  in Journal of heat transfer > Vol. 133 N° 7 (Juillet 2011) . - pp. [072601/1-9] Titre : Forced convection in a channel partly occupied by a bidisperse porous medium : symmetric case Type de document : texte imprimé Auteurs : D. A. Nield, Auteur ; Andrey V. Kuznetsov, Auteur Année de publication : 2011 Article en page(s) : pp. [072601/1-9] Note générale : Physique Langues : Anglais (eng) Mots-clés : Bidisperse  porous  medium  Forced  convection  Channel  Beavers-Joseph  condition Index. décimale : 536 Chaleur. Thermodynamique Résumé : An analytic solution is obtained for the problem of fully developed forced convection in a channel between parallel plane walls, partly occupied by a bidisperse porous medium (BDPM) and partly by a fluid clear of solid material, the distribution of material being symmetrical with the BDPM forming either the core or the sheath portion of the channel. The case of uniform flux boundaries is considered. For the porous medium, a two-velocity two-temperature model based on Darcy's law is employed and the Beavers–Joseph interface condition is imposed. In each case, Nusselt number values are obtained in terms of various parameters. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO00013300 [...] [article] Forced convection in a channel partly occupied by a bidisperse porous medium : symmetric case [texte imprimé] / D. A. Nield, Auteur ; Andrey V. Kuznetsov, Auteur . - 2011 . - pp. [072601/1-9]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 133 N° 7 (Juillet 2011) . - pp. [072601/1-9] Mots-clés : Bidisperse  porous  medium  Forced  convection  Channel  Beavers-Joseph  condition Index. décimale : 536 Chaleur. Thermodynamique Résumé : An analytic solution is obtained for the problem of fully developed forced convection in a channel between parallel plane walls, partly occupied by a bidisperse porous medium (BDPM) and partly by a fluid clear of solid material, the distribution of material being symmetrical with the BDPM forming either the core or the sheath portion of the channel. The case of uniform flux boundaries is considered. For the porous medium, a two-velocity two-temperature model based on Darcy's law is employed and the Beavers–Joseph interface condition is imposed. In each case, Nusselt number values are obtained in terms of various parameters. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO00013300 [...]

The effect of local thermal nonequilibrium on the onset of convection in a nanofluid / D. A. Nield in Journal of heat transfer, Vol. 132 N° 5 (Mai 2010) 

Public ISBD [article]  in Journal of heat transfer > Vol. 132 N° 5 (Mai 2010) . - pp. [052405-1/7] Titre : The effect of local thermal nonequilibrium on the onset of convection in a nanofluid Type de document : texte imprimé Auteurs : D. A. Nield, Auteur ; Andrey V. Kuznetsov, Auteur Article en page(s) : pp. [052405-1/7] Note générale : Physique Langues : Anglais (eng) Mots-clés : Nanofluid  Brownian  motion  Thermophoresis  Rayleigh-Bénard  problem  Local  thermal  nonequilibrium Index. décimale : 536 Chaleur. Thermodynamique Résumé : The onset of convection in a horizontal layer of a nanofluid is studied analytically. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis, and allows for local thermal nonequilibrium (LTNE) between the particle and fluid phases. The analysis reveals that in some circumstances, the effect of LTNE can be significant, but for a typical dilute nanofluid (with large Lewis number and with small particle-to-fluid heat capacity ratio), the effect is small. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&smode=strresults& [...] [article] The effect of local thermal nonequilibrium on the onset of convection in a nanofluid [texte imprimé] / D. A. Nield, Auteur ; Andrey V. Kuznetsov, Auteur . - pp. [052405-1/7]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 132 N° 5 (Mai 2010) . - pp. [052405-1/7] Mots-clés : Nanofluid  Brownian  motion  Thermophoresis  Rayleigh-Bénard  problem  Local  thermal  nonequilibrium Index. décimale : 536 Chaleur. Thermodynamique Résumé : The onset of convection in a horizontal layer of a nanofluid is studied analytically. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis, and allows for local thermal nonequilibrium (LTNE) between the particle and fluid phases. The analysis reveals that in some circumstances, the effect of LTNE can be significant, but for a typical dilute nanofluid (with large Lewis number and with small particle-to-fluid heat capacity ratio), the effect is small. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&smode=strresults& [...]

The onset of convection in a layer of cellular porous material / D. A. Nield in Journal of heat transfer, Vol. 132 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [074503-1/4] Titre : The onset of convection in a layer of cellular porous material : effect of temperature-dependent conductivity arising from radiative transfer Type de document : texte imprimé Auteurs : D. A. Nield, Auteur ; Andrey V. Kuznetsov, Auteur Article en page(s) : pp. [074503-1/4] Note générale : Physique Langues : Anglais (eng) Mots-clés : Cellular  porous  medium  Radiative  heat  transfer  Temperature-dependent  conductivity  Onset  of  convection  Horton-Rogers-Lapwood  problem Index. décimale : 536 Chaleur. Thermodynamique Résumé : The onset of convection in a horizontal layer of a cellular porous material heated from below is investigated. The problem is formulated as a combined conductive-convective-radiative problem in which radiative heat transfer is treated as a diffusion process. The problem is relevant to cellular foams formed from plastics, ceramics, and metals. It is shown that the variation of conductivity with temperature above that of the cold boundary leads to an increase in the critical Rayleigh number (based on the conductivity of the fluid at that boundary temperature) and an increase in the critical wave number. On the other hand, the critical Rayleigh number based on the conductivity at the mean temperature decreases with increase in the thermal variation parameter if the radiative contribution to the effective conductivity is sufficiently large compared with the nonradiative component. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] [article] The onset of convection in a layer of cellular porous material : effect of temperature-dependent conductivity arising from radiative transfer [texte imprimé] / D. A. Nield, Auteur ; Andrey V. Kuznetsov, Auteur . - pp. [074503-1/4]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [074503-1/4] Mots-clés : Cellular  porous  medium  Radiative  heat  transfer  Temperature-dependent  conductivity  Onset  of  convection  Horton-Rogers-Lapwood  problem Index. décimale : 536 Chaleur. Thermodynamique Résumé : The onset of convection in a horizontal layer of a cellular porous material heated from below is investigated. The problem is formulated as a combined conductive-convective-radiative problem in which radiative heat transfer is treated as a diffusion process. The problem is relevant to cellular foams formed from plastics, ceramics, and metals. It is shown that the variation of conductivity with temperature above that of the cold boundary leads to an increase in the critical Rayleigh number (based on the conductivity of the fluid at that boundary temperature) and an increase in the critical wave number. On the other hand, the critical Rayleigh number based on the conductivity at the mean temperature decreases with increase in the thermal variation parameter if the radiative contribution to the effective conductivity is sufficiently large compared with the nonradiative component. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...]