The effect of an imposed magnetic field on Rayleigh–Bénard three-dimensional natural convection was investigated numerically. The cubical cavity is heated from below and cooled from above, and the remaining side walls are insulated. The magnetic field is tilted at an angle α about the horizontal. Flow field and heat transfer were predicted for fluid with $\mathit{Pr}=0.71$ and a wide range of governing parameters such as a Rayleigh number between $5\times {10}^{4}$ and 10^{5}, a Hartmann number between 0 and 60, and an inclination angle between 0° and 360°. When a magnetic field is applied on a non-conducting fluid within a cubical cavity, whether the natural convection is promoted or damped is found to depend on both the direction and the magnitude of the magnetic field. The average Nusselt number decreased with an increase of the Hartmann number and increased with an increase of the Rayleigh number. The maximum heat transfer rate was observed for $\alpha =30$° and $\mathit{Ha}=10$, while heat transfer was poor for the vertical direction of the magnetic field. The dependence of the promotion or damping efficiency on α and Ha is also discussed in terms of isocontours and isosurfaces in sight of the dynamic and thermal behaviour of the flow.

Accepted:

Published online:

Awatef Naffouti ^{1};
Brahim Ben-Beya ^{1};
Taieb Lili ^{1}

@article{CRMECA_2014__342_12_714_0, author = {Awatef Naffouti and Brahim Ben-Beya and Taieb Lili}, title = {Three-dimensional {Rayleigh{\textendash}B\'enard} magnetoconvection: {Effect} of the direction of the magnetic field on heat transfer and flow patterns}, journal = {Comptes Rendus. M\'ecanique}, pages = {714--725}, publisher = {Elsevier}, volume = {342}, number = {12}, year = {2014}, doi = {10.1016/j.crme.2014.09.001}, language = {en}, }

TY - JOUR AU - Awatef Naffouti AU - Brahim Ben-Beya AU - Taieb Lili TI - Three-dimensional Rayleigh–Bénard magnetoconvection: Effect of the direction of the magnetic field on heat transfer and flow patterns JO - Comptes Rendus. Mécanique PY - 2014 SP - 714 EP - 725 VL - 342 IS - 12 PB - Elsevier DO - 10.1016/j.crme.2014.09.001 LA - en ID - CRMECA_2014__342_12_714_0 ER -

%0 Journal Article %A Awatef Naffouti %A Brahim Ben-Beya %A Taieb Lili %T Three-dimensional Rayleigh–Bénard magnetoconvection: Effect of the direction of the magnetic field on heat transfer and flow patterns %J Comptes Rendus. Mécanique %D 2014 %P 714-725 %V 342 %N 12 %I Elsevier %R 10.1016/j.crme.2014.09.001 %G en %F CRMECA_2014__342_12_714_0

Awatef Naffouti; Brahim Ben-Beya; Taieb Lili. Three-dimensional Rayleigh–Bénard magnetoconvection: Effect of the direction of the magnetic field on heat transfer and flow patterns. Comptes Rendus. Mécanique, Volume 342 (2014) no. 12, pp. 714-725. doi : 10.1016/j.crme.2014.09.001. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2014.09.001/

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