Effects of a Heated Strip Arrangement on Heat Transfer Rate in Cubical Enclosures

This work addresses a numerical approach based on the finite volume method and a full multi-grid technique to study three-dimensional flow structures and heat transfer rates in cubical cavity partially heated from one wall. The working fluid is air so that the Prandtl number equates to $0.71$. Numerical solutions are generated for representative values of the controlling Rayleigh number inside the range $10^3 \le \text{Ra} \le 10^7$. The heating occurs with a heated strip placed inside the enclosure. Three scenarios are investigated: (i) the heated source is mounted on the bottom horizontal wall, (ii) the heated source is mounted horizontally on the lateral wall, and (iii) the heated source is mounted vertically on the lateral wall. Effects of heated strip position in the enclosure on heat transfer are studied. It is shown that suitable configuration which generates highest heat transfer rate through the heated strip is depending on Rayleigh number. Results are presented in the form of projection of flow lines and isotherms plots as well as the variation of the Nusselt number and the average temperature at the heat source surface for all configurations computed in this study.