Conjugate heat transfer by conduction and natural convection on a heated vertical wall

We present a numerical and experimental study of conjugate heat transfer by conduction and natural convection on a heated vertical wall. The system considered is a wall subject to uniform heat flux on one side and cooled on both sides by natural convection of surrounding air. The equations of mass, momentum and energy conservations are solved by the control volume method - Simpler algorithm. The non-dimensional wall thickness is varied from 0.02 to 0.10, the wall to air conductivity ratio from 1 to 100 and Rayleigh number from 10(3) to 10(9). The results are presented in terms of Nusselt number on both surfaces as a function of Rayleigh number, and in terms of governing parameters of wall thickness and conductivity ratio. It is found that Nusselt number is a strong function of Rayleigh number and wall thickness, and a weak function of conductivity ratio. The effect of conduction on natural convection heat transfer is not negligible and it may be from 40% for thin walls to 12% for thick walls. We derived useful correlations for design studies. (C) 2008 Elsevier Ltd. All rights reserved.