Mathematical Problems in Engineering
Volume 2012 (2012), Article ID 253965, 10 pages
Research Article

Transient Natural Convection in Porous Square Cavity Heated and Cooled on Adjacent Walls

1Unit of Mathematics and Statistics, Universiti Teknologi MARA Pahang, 26400 Bandar Jengka, Malaysia
2Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia
3School of Information Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia

Received 12 December 2011; Accepted 31 January 2012

Academic Editor: Kue-Hong Chen

Copyright © 2012 M. S. Selamat et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Transient natural convection in a square cavity filled with a porous medium is studied numerically. The cavity is assumed heated from one vertical wall and cooled at the top, while the other walls are kept adiabatic. The governing equations are solved numerically by a finite difference method. The effects of Rayleigh number on the initial transient state up to the steady state are investigated for Rayleigh number ranging from 10 to 2 × 1 0 2 . The evolutions of flow patterns and temperature distributions were presented for Rayleigh numbers, R a = 1 0 2 and 1 0 3 . It is observed that the time taken to reach the steady state is longer for low Rayleigh number and shorter for high Rayleigh number.