THERMAL SCIENCE

International Scientific Journal

FREE CONVECTION IN A VERTICAL CYLINDRICAL ANNULUS FILLED WITH ANISOTROPIC POROUS MEDIUM

ABSTRACT
A numerical study has been carried out for free convection in a vertical cylindrical annulus filled with a porous medium and whose inner wall is isothermally heated and the outer wall is isothermally cooled, the horizontal walls being insulated. The porous medium is assumed to be both hydrodynamically and thermally anisotropic. Numerical results are reported for 0.1 ≤ K*≤ 10, 0.1 ≤ λ ≤ 10,1 ≤ A ≤ 20,2 ≤ Rr ≤ 20, and Ra*≤ 10000. Anisotropy of the porous medium is found to affect fluid flow, temperature distribution and heat transfer significantly. Higher permeability in the vertical direction enhances convective flow intensity and heat transfer inside the annulus. Average Nusselt number on the inner hot wall increases with increase in Rayleigh number or radius ratio, while it decreases with increase in aspect ratio or permeability ratio. The influence of thermal anisotropy is not so significant as that of hydrodynamic anisotropy. The numerically predicted temperature distribution at various locations inside the annulus shows reasonable agreement with experimental results available for isotropic porous medium. Based on a parametric study, correlation for heat transfer is presented in terms of Rayleigh number, aspect ratio, radius ratio, and permeability ratio.
KEYWORDS
PAPER SUBMITTED: 2007-08-18
PAPER REVISED: 2008-09-11
PAPER ACCEPTED: 2008-12-08
DOI REFERENCE: https://doi.org/10.2298/TSCI0901037T
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2009, VOLUME 13, ISSUE 1, PAGES [37 - 45]
REFERENCES
  1. Havstad, M. A., Burns, P. J., Convective Heat Transfer in Vertical Cylindrical Annuli Filled with Porous Medium, Int. J. Heat Mass Transf., 25 (1982), 11, pp. 1755-1766
  2. Reda, D. C., Natural Convection Experiments in a Liquid Saturated Porous Medium Bounded by Vertical Coaxial Cylinders, ASME J. Heat Transfer, 105 (1983), 4, pp. 795-802
  3. Prasad, V., Kulacki, F. A., Natural Convection in a Vertical Porous Annulus, Int. J. Heat Mass Transf., 27 (1984), 2, pp. 207-219
  4. Prasad, V., Kulacki, F. A., Natural Convection in Porous Media Bounded by Short Concentric Cylinders, ASME J. Heat Transfer, 107 (1985), 1, pp. 147-154
  5. Prasad, V., Kulacki, F. A., Keyhani, M., Natural Convection in Porous Media, J. Fluid Mechanics, 150 (1985), 3, pp. 89-119
  6. Hickox, C. E., Gartling, D. K., A Numerical Study of Natural Convection in a Vertical Annular Porous Layer, Int. J. Heat Mass Transf., 28 (1985), 3, pp. 720-723
  7. Shivakumara, I. S., Prasanna, B. M .R., Rudraiah, N., Venkatachalappa, M., Numerical Study of Natural Convection in a Vertical Cylindrical Annulus Using a Non-Darcy Equation, J. Porous Media, 5 (2003), 2, pp. 87-102
  8. Ni, J., Beckermann, C., Natural Convection in a Vertical Enclosure Filled with Anisotropic Porous Media, ASME J. Heat Transfer, 113 (1991), 4, pp. 1033-1037
  9. Chang, W. J., Haiso, C. F., Natural Convection in a Vertical Cylinder Filled with Anisotropic Porous Media, Int. J. Heat Mass Transf., 36 (1993), 5, pp. 3361-3367
  10. Parthiban, C., Patil, P. R., Thermal Instability in an Anisotropic Porous Medium with Internal Heat Source and Inclined Temperature Gradient, Int. Commun. Heat Mass Transfer, 24 (1997), 7, pp. 1049-1058
  11. Dhanasekaran, M. R., Das Sarit, K., Venkateshan, S. P., Natural Convection in a Cylindrical Enclosure Filled with Heat Generating Anisotropic Porous Medium, ASME J. Heat Transfer, 124 (2002), 1, pp. 203-207
  12. Suresh, Ch. S. Y., Vamsee Krishna, Y., Sundararajan, T., Das Sarit, K., Numerical Simulation of Three-Dimensional Natural Convection Inside a Heat Generating Anisotropic Porous Medium, Heat Mass Transfer, 41 (2005), 9, pp. 799-809

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