# SIMULATION OF NATURAL CONVECTION HEAT TRANSFER USING NANOFLUID IN A CONCENTRIC ANNULUS

## Main Article Content

## Abstract

In the present study, natural convection of nanofluids in a concentric horizontal annulus enclosure has been numerically simulated using the lattice Boltzmann method. A water-based nanofluid containing Al_{2}O_{3} nanoparticle has been studied. Simulations have been carried while the Rayleigh number ranges from 10^{3} to 10^{5} and solid volume fraction varies between 0 and 0.04. The effects of solid volume fraction of nanofluids on hydrodynamic and thermal characteristics such as average and local Nusselt numbers, streamlines and isotherm patterns for different values of solid volume fraction, annulus gap width ratio and Rayleigh number are investigated and discussed in detail.

## Article Details

**Thermal Science**, [S.l.], mar. 2017. ISSN 2334-7163. Available at: <http://thermal-science.tech/journal/index.php/thsci/article/view/2111>. Date accessed: 23 june 2017. doi: https://doi.org/10.2298/TSCI150118078F.

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Accepted 2017-03-13

Published 2017-03-13

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