Numerical Solution of Natural Convective Heat Transfer of Al2O3/Water Nanofluids in a Square Cavity with Modified Circular Corners

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Abstract

In this paper, Natural convection heat transfer of Al2O3/Water nanofluid in a square enclosure has been studied numerically. To do so, corners of square enclosure were modified by rounding its edges. According to the new variable properties model, dynamic viscosity and thermal conductivity depend on the diameter of the particles, concentration and temperature. Therefore, the enclosure has been bounded by adiabatic top and bottom horizontal walls and isothermal side walls. The governing equations of continuity, momentum and energy have been developed for nanofluid. Finite Volume Method (FVM) with structured grids has been applied to solve these equations. The discrete equations have been written by the discrete method in time and space using FORTRAN codes. The Grashof and Prandtl numbers have been studied by changing the parameters such as non-uniform distribution of nanoparticles, average diameter and volume fraction of nanoparticles in the various geometries. The results indicated that nanofluid has significant positive effect on convective heat transfer coefficient and the Nusselt number. Also, the Nusselt number for increase , and for Grashof numbers of , and , respectively. Furthermore, by increasing R parameter and nano particle volume fraction, Nusselt number increased.

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Journal of Solid and Fluid Mechanics
Volume 7, Issue 1
March and April 2017
Pages 315-328

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