0
Research Papers: Natural and Mixed Convection

Non-Darcy Natural Convection From a Vertical Cylinder Embedded in a Thermally Stratified and Nanofluid-Saturated Porous Media

[+] Author and Article Information
A. M. Rashad

Department of Mathematics,
Faculty of Science,
Aswan University,
Aswan, Egypt

S. Abbasbandy

Department of Mathematics,
Science and Research Branch,
Islamic Azad University,
Tehran, Iran
e-mail: abbasbandy@yahoo.com

Ali J. Chamkha

Manufacturing Engineering Department,
The Public Authority for Applied Education and Training,
Shuweikh 70654, Kuwait

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received February 13, 2013; final manuscript received June 18, 2013; published online November 12, 2013. Assoc. Editor: Andrey Kuznetsov.

J. Heat Transfer 136(2), 022503 (Nov 12, 2013) (9 pages) Paper No: HT-13-1078; doi: 10.1115/1.4025559 History: Received February 13, 2013; Revised June 18, 2013

In recent years, nanofluids have attracted attention as a new generation of heat transfer fluids in building heating, heat exchangers, plants, and automotive cooling applications because of their excellent thermal performance. Various benefits of the application of nanofluids include improved heat transfer, heat transfer system size reduction, minimal clogging, microchannel cooling, and miniaturization of systems. In this paper, a study of steady, laminar, natural convection boundary-layer flow adjacent to a vertical cylinder embedded in a thermally stratified nanofluid-saturated non-Darcy porous medium is investigated. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis, and a generalized porous media model, which includes inertia and boundary effects, is employed. The cylinder surface is maintained at a constant nanoparticles volume fraction, and the wall temperature is assumed to vary with the vertical distance according to the power law form. The resulting governing equations are nondimensionalized and transformed into a nonsimilar form and then solved by Keller box method. A comparison is made with the available results in the literature, and our results are in very good agreement with the known results. A parametric study of the physical parameters is made, and a representative set of numerical results for the velocity, temperature, and volume fraction, as well as local shear stress and local Nusselt and Sherwood numbers, are presented graphically. The salient features of the results are analyzed and discussed. The results indicate that, when the buoyancy ratio or modified Grashof number increases, all of the local shear stress, local Nusselt number, and the local Sherwood number enhance while the opposite behaviors are predicted when the thermophoresis parameter increases. Moreover, increasing the value of the surface curvature parameter leads to increases in all of the local shear stress and the local Nusselt and Sherwood numbers while the opposite behaviors are obtained when either of the thermal stratification parameter or the boundary effect parameter increases.

FIGURES IN THIS ARTICLE
<>
Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 5

Effects of Nt and m on the local (a) shear stress; (b) Nusselt number; and (c) Sherwood number

Grahic Jump Location
Fig. 4

Effects of Nb and ω on the (a) velocity; (b) temperature profiles; and (c) nanoparticles volume fraction profiles

Grahic Jump Location
Fig. 3

Effects of Nr and Gr on the local (a) shear stress; (b) Nusselt number; and (c) Sherwood number

Grahic Jump Location
Fig. 2

Effects of Nr and Gr on the (a) velocity; (b) temperature profiles; and (c) nanoparticles volume fraction profiles

Grahic Jump Location
Fig. 1

The physical model and coordinate system

Grahic Jump Location
Fig. 6

Effects of Nt and m on the (a) velocity; (b) temperature profiles; and (c) nanoparticles volume fraction profiles

Grahic Jump Location
Fig. 7

Effects of Nt and m on the local (a) shear stress; (b) Nusselt number; and (c) Sherwood number

Grahic Jump Location
Fig. 8

Effects of Le and Bp on the (a) velocity; (b) temperature profiles; and (c) nanoparticles volume fraction profiles

Grahic Jump Location
Fig. 9

Effects of Le and Bp on the local (a) shear stress; (b) Nusselt number; and (c) Sherwood number

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In