Modeling of Rayleigh-Bénard natural convection heat transfer in nanofluids

Bilal Elhajjar (1) , Glades Bachir (1, 2) , Abdelkader Mojtabi (1) , Chakib Fakih (2) , Marie-Catherine Charrier-Mojtabi (3)

1 IMFT - Institut de mécanique des fluides de Toulouse
2 LU / ULB - الجامعة اللبنانية [بيروت] = Lebanese University [Beirut] = Université libanaise [Beyrouth]
3 PHASE - Laboratoire Physique de l'Homme Appliquée à Son Environnement

Heat transfer in Rayleigh-Bénard convection is investigated for three types of nanofluid. Instead of using the expressions commonly found in the literature for specific heat capacity and thermal expansion coefficient, we used two relations that are in agreement with the laws of thermodynamics. The influence of nanoparticles on conductive and convective heat transfer is studied. It is shown that adding nanoparticles in a fluid delays the onset of convection. Contrary to what is argued by many authors, we prove by direct numerical simulations that the use of nanofluids can reduce heat transfer instead of increasing it.

Mots clés: Heat transfer; Convection; Nanofluid; Rayleigh-Bénard

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Bilal Elhajjar, Glades Bachir, Abdelkader Mojtabi, Chakib Fakih, Marie-Catherine Charrier-Mojtabi. Modeling of Rayleigh-Bénard natural convection heat transfer in nanofluids. Comptes Rendus Mécanique, 2010, vol. 338, pp. 350-354. ⟨10.1016/j.crme.2010.07.008⟩. ⟨hal-00965752⟩