mehdi ahmadi


In this paper, to achievement the effect of increase number of heating components arrangement on the rate of heat transfer of natural convection, that others have been less noticed. Therefore, in each stage increase the number of heating components so much the space occupied by them remains constant. Then by calculating the amount of heat transfer in different Rayleigh number became clear that minify and distributing heating solid phase in the enclosure increases the total Nusselt number and heat transfer, One reason could be high intensity of fluid motion in corners and near walls of the enclosure. In the next section with the solid phases on the enclosure can be made porous media model. As the results showed an increase in average Rayleigh number, Nusselt number has increased. Also be seen in the lower Darcy numbers, speed of increase in Nusselt number with increase in average Rayleigh number is higher. It can be said that in enclosure by any number of solid pieces with certain Darcy number, with an increase in average Rayleigh number, circular flow inside the enclosure becomes more intense and isothermal lines near walls with constant temperature are so dense, that represents an increase in rate of heat transfer. Also by increasing the Darcy number, rate of heat transfer from the porous media has decreased, as regards that a large share of heat transfer in porous media is done by conduction, although increasing Darcy number increases heat transfer of natural convection but decrease a heat transfer of conduction, therefore decrease total of heat transfer.

Full Text:



Merrikh, A.A, Mohamad, A.A, Enhanc, J, Heat Transf. 8-1, 55. 2001.

Merrikh, A.A, Lage, J.L, Mohamad, A.A, in: Z. Chen, R. Erwin (Eds.), Comparison between Pore-Level and Porous Medium Models for Natural Convection in a Non-Homogeneous Enclosure, Fluid Flow and Transport in Porous Media: Mathematical and Numerical Treatment, Contemporary Mathematics, vol. 295, p. 387. 2002.

Massarotti, N, Nithiarasu, P, Carotenuto, A, Numer, J, Methods Heat Fluid Flow 13 (7), 862. 2003.

Sezai, I, Mohamad, A.A, "Natural convection from a discrete heat source on the bottom of a horizontal enclosure" International Journal of Heat and Mass Transfer 43, 2257-2266. 2000.

Ali A. Merrikh, Jose´ L. Lage. Natural convection in an enclosure with disconnected and conducting solid blocks - International Journal of Heat and Mass Transfer 48, 1361–1372. 2005.

Braga, E.J, de Lemos, m.j.s, laminar natural convection in cavities filled with circular and square rods. (2005) International Communications in Heat and Mass Transfer 32, 1289–1297. 2005.

Braga, E.J, de Lemos, m.J.S, "Heat transfer in enclosures having a fixed amount of solid material simulated with heterogeneous and homogeneous models", International Journal of Heat and Mass Transfer 48.4748–4765. 2005.

Bejan, A, Kraus, A, Heat Transfer Handbook, USA, 2003.

De Vahl Davis, G, Natural convection in a square cavity: Abenchmark numerical solution, Int. J. Numer. Methods Fluids 3 (1983) 249–264.

House, J.M, Beckermann, C, Smith, T.F, Effect of a centered conducting body on atural heat transfer in a enclosure, Numer. Heat Transfer A 18 (1990) 213–225.

Kalita, J.C, Dalal, D.C, Dass, A.K, Fully compact higherorder computation of steady state natural convection in a square cavity, Phys. Rev. E 64-066703, 1–13. 2001.

Merrikh, A.A, Lage, J.L, Effect of distributing a fixed amount of solid constituent inside a porous medium enclosure on the heat transfer process, in: ICAPM 2004 — Proceedings of International Conference on Applications of Porous Media, pp. 51–57. 2004.

ISSN:    1511-788X
E-ISSN: 2289-7860

Creative Commons License
IIUM Engineering Journal by is licensed under a Creative Commons Attribution 4.0 International License