Conjugate Natural Convection in a Square Cavity Heated From Below

Abstract

This paper presents numerical results for two-dimensional steady-state natural convection in a square cavity. The upper and lower walls are kept at different constant temperatures, whereas the lateral walls have certain thickness and thermal conductivity and are externally insulated. Under these conditions we deal with a conjugate natural convection problem in which the heat conduction in the lateral walls is coupled with the internal convection. The continuity, momentum and energy equations were solved by using the finite volume method. The results here presented include: (i) the temperature distribution in the lateral walls and in the fluid, (ii) the velocity field, and (iii) the average Nusselt number at the upper and lower walls. It was found that the steady state fluid flow is strongly dependent on the initial temperature condition, when the fluid is initially at rest. The PIV technique allowed us to get some experimental data by measuring the velocity field in a two-dimensional square cavity. A good agreement between numerical and experimental results was found.

Using of Bejan's Heatline Technique for Analysis of Natural Convection in a Divided Cavity with Differentially Changing Conductive Partition

“…As seen, the passive area in which heat in circulated are also expanded. Figure 4 shows streamlines (on the left), isotherms (on the middle) and heatlines (on the right) at different thicknesses of partition for k ¼ 10 and Ra ¼ 10 5 . In this case, the thin part is taken as fixed but the thickness of the bottom part is changed.…”

“…Validation of the present code was performed by considering two different studies from the available literature by Kaminski and Prakash [1] and Sanchez et al [5]. In their work, the cavity is filled with a single viscous fluid and bounded by single or double walls with finite length and different thermal conductivity.…”

“…They observed that inclination angle and other governing parameters were also used as control parameters for heat and fluid flow. Sanchez et al [5] carried out numerical and experimental analyses for conjugate natural convection in a square cavity heated from below. They used the particle image velocimeter (PIV) technique to obtain the velocity field inside the enclosure.…”

Effects of inclination angle on conduction—natural convection in divided enclosures filled with different fluids

“…Validation of the present code was performed by two different studies from available literature as Kaminski and Prakash [19] and Sanchez et al [20]. In their case, the cavity is filled with single viscous fluid and bounded by single or double walls with finite length and thermal conductivity.…”

“…They indicated that inclination angle has a strong influence on heat transfer. Other studies can be found on natural convection in enclosures with single or multiple partitions in literature [17][18][19][20][21].…”