Heat transfer inside cavities heated by discrete sources: Solar systems

In this paper, we studied numerically laminar natural convection in two types of configurations: the first a square enclosure with four types of discrete sources (Plane, Circular, Square and Triangular) with partial heating of the bottom wall while the rest is maintained constantly adiabatic. The second configuration a rectangular enclosure in which we increased the number of discrete sources for each geometric shape. This study simulates the case of heat generation in a storage tank of hot water or in an electronic component mounting enclosure. The light source is considered to be located in the lower wall with a heated fixed width. This heating will be introduced either as an isothermal or uniform flow. For the purposes of this analysis, the length of the source is set at 20% of the total length of the lower wall. The upper wall, the unheated portion of the bottom wall, the right and left walls will be considered adiabatic. For all configurations the Rayleigh number was fixed at 106. The streamlines and isotherms are presented for various combinations of forms of the heated zone. The results will also be presented in a number of local Nusselt on heated wall.