This paper presents a numerical study that concerning the effect of surface radiation on
natural convection cooling of four discrete isoflux heaters flush-mounted on a vertical wall
of an air filled rectangular enclosure. The opposite side is isothermally cooled while the
top and bottom sides as well as the spacing between the heaters are kept adiabatic. Twodimensional
mathematical model was developed based on solving the partial differential
equations for the conservation of mass, momentum, and energy. A laminar flow is to be
considered in the present model. Galerkin finite element method was utilized for the model
formulation.
A numerical simulation is carried out to examine the parametric effects of enclosure aspect
ratio, Rayleigh number, heater emissivity, adiabatic and cold surfaces emissivities, and the
radiation parameter on the role played by the surface radiation in heat dissipation from the
discrete heaters in the enclosure. The computed model results were verified through the
comparison with those experimental results available in the literature and good agreement
between them were noticed.
Several correlation equations in terms of aspect ratio, Rayleigh number, heater surface
emissivity and the radiation parameter for the average Nusselt number for heaters, its
radiative and convective components as well as the maximum surface temperature at the
discrete heaters are obtained. |
