Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.
The natural convective heat transfer rate from a relatively
narrow heated vertical plate with a uniform heat flux over its
surface has been numerically studied. This heated plate is
embedded in a large plane adiabatic surface, the surface of the
heated plate being somewhat “below” that of the adiabatic
surface, i.e., the heated plate surface is recessed in the adiabatic
surface. The main aim of the present work was to study how the
recessing of the heated plate into the surface affects the mean
heat transfer rate from the plate. It has been assumed that the
flow is steady and laminar and that the fluid properties are
constant except for the density change with temperature which
gives rise to the buoyancy forces, this having been treated by
using the Boussinesq approach. It has also been assumed that
the flow is symmetrical about the vertical centre-plane of the
plate. The solution has been obtained by numerically solving
the full three-dimensional form of the governing equations,
these equations being written in dimensionless form. The
solution was obtained using a commercial finite element
method based code, FIDAP. The solution has the Rayleigh
number based on the plate height and the surface heat flux, the
dimensionless plate width, the dimensionless depth that the
heated plate is recessed into the adiabatic surface, and the
Prandtl number as parameters. Results have only been obtained
for Pr = 0.7. A relatively wide range of values of the other
input parameters have been considered and the effects of these
parameters on the mean Nusselt number have been determined
and used to study the effects that arise due to the plate being
recessed and that arise due to the fact that the plate is relatively
narrow.
