Journal of New Technology and Materials
Volume 12, Numéro 2, Pages 43-53
2022-12-20

Numerical Approach Of Natural Convection In Eccentric Annular Spaces Filled With Hybrid Nanofluids

Authors : Allouche Billel . Djezzar Mahfoud . Tayebi Tahar . Allouche Selmane .

Abstract

A numerical analysis of free convection in two horizontal eccentric cylinders filled with a Al2O3-TiO2/water hybrid nanofluid is performed in this paper. The two internal and external cylindrical walls are maintained respectively at the temperature Th and Tc with Th>Tc. A theoretical correlation of thermal conductivity of the hybrid nanofluid was used in this study. The problem is treated by dimensionless governing equations formulated in bipolar coordinates and solved by the finite volume method. The effects of the Rayleigh number and the hybrid nanofluid volume fraction on the heat transfer by natural convection are examined. The results are presented according to isotherms, streamlines and average and local Nusselt numbers. It was found that the inclusion of nanoparticles in the base fluid produced an increase in the heat transfer rate compared to the pure fluid. Increasing the volume fraction of the hybrid nanofluid improves the heat transfer rate for different Rayleigh number values.

Keywords

Natural convection ; Heat transfer ; Hybrid Nanofluid ; Eccentric annular space