Natural convection in a rectangular cavity filled with nanofluids: Effect of variable viscosity
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 27 July 2018
Issue publication date: 8 August 2018
Abstract
Purpose
This paper aims to develop a numerical study of the steady natural convection in a rectangular cavity filled with the CuO–water-based nanofluid. It is assumed that the viscosity of nanofluids depends on the temperature and on the nanofluids volume fraction.
Design/methodology/approach
The mathematical nanofluid model has been formulated on the basis of the model proposed by Buongiorno (2006). The system of partial differential equations is written in terms of a dimensionless stream function, vorticity, temperature and the volume fraction of the nanoparticles, and is solved numerically using the finite difference method for different values of the governing parameters.
Findings
It is found that both fluid flow and heat transfer coefficient are affected by the considered parameters. Thus, the Nusselt number is slowly increasing with increasing volume fraction from 2 per cent to 5 per cent and it is more pronounced increasing with increasing Rayleigh number from 103 to 105.
Originality/value
Buongiorno’s (2006) nanofluid model has been applied for the flow with the characteristics as mentioned in the paper. A comprehensive survey on the behavior of flow and heat transfer characteristics has been presented. All plots presented in the paper are new and are not reported in any other study.
Keywords
Acknowledgements
The authors wish to express their thanks to the very competent reviewers for their good comments and suggestions. In addition, the three authors, Revnic, Groşan and Pop, wish to mention that the present work has been partially supported from the grant PN-III-P4-ID-PCE-2016-0036, UEFISCDI, Romania.
Citation
Revnic, C., Abu-Nada, E., Grosan, T. and Pop, I. (2018), "Natural convection in a rectangular cavity filled with nanofluids: Effect of variable viscosity", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 28 No. 6, pp. 1410-1432. https://doi.org/10.1108/HFF-06-2017-0244
Publisher
:Emerald Publishing Limited
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