Modelling of combined surface radiation and natural convection in a vented “T” form cavity

In this paper, a numerical study of heat transfer and fluid flow in a “T” form cavity is carried out. The cavity contains two symmetrically identical isothermal blocks and is vented by two opening located in a vertical median axis at the top and the bottom parts of the cavity. A specifically developed numerical model, based on the finite-volume method, is used for the solutions of the governing differential-equations. The coupling of the velocity–pressure is treated by the Simpler algorithm. A special attention is given to study the effects of block height, opening size, Rayleigh number and surface emissivity of blocks and walls. Effects of different parameters on streamlines, temperature fields and average Nusselt-number are discussed. It is found that the radiative exchanges produce an increase of the average Nusselt-number. This one increases almost linearly with increasing the Rayleigh number Ra, and it becomes more important when the solid blocks heights are large.