Natural convection heat transfer in a nanofluid-filled trapezoidal enclosure

Heat transfer enhancement utilizing nanofluids in a trapezoidal enclosure is investigated for various per�tinent parameters. Transport equations are modelled by a stream-vorticity formulation and solved numerically by finite difference approach. The inclined sloping boundaries is treated by adoptin...

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Bibliographic Details
Main Authors: Saleh, H., Roslan, R., Hashim, I.
Format: Article
Language:English
Published: Elsevier 2011
Subjects:
Online Access:http://eprints.uthm.edu.my/7972/1/J3967_dd4259c28c14fbace1eead6a6087ac3a.pdf
Description
Summary:Heat transfer enhancement utilizing nanofluids in a trapezoidal enclosure is investigated for various per�tinent parameters. Transport equations are modelled by a stream-vorticity formulation and solved numerically by finite difference approach. The inclined sloping boundaries is treated by adopting stair�case-like zigzag lines. Based upon the numerical predictions, the effects of Grashof number, inclination angle of the sloping wall, volume fraction of nanoparticles on flow and temperature patterns as well as the heat transfer rate within the enclosure are presented. Water–Cu and water–Al2O3 nanofluids were tested. We found that acute sloping wall and Cu nanoparticles with high concentration are effective to enhance the rate of heat transfer. We also developed a new correlation for the average Nusselt number as a function of the angle of the sloping wall, effective thermal conductivity and viscosity as well as Gras�hof number