The work reported in this paper is a study of airflow and heat transfer for low turbulent buoyancy-driven flow in a rectangular cavity partially filled with solid cylindrical obstacles. The two vertical walls were maintained at constant temperatures giving a temperature differential of 42.2oC and Rayleigh number of 1.45 x 109. An experimental thermal rig was designed and fabricated as part of the research programme. A systematic numerical investigation has been carried out by validating the numerical results against experimental data collected during this research. Steady state temperature data for the mid-height and mid-width of the cavity displayed a stable core region and the average core temperature was found to be significantly influenced by the product (solid objects) arrangement along the horizontal and vertical directions respectively. It is believed that the results reported in this paper would be valuable for a greater understanding of the complex thermo-fluidic process.