Natural convection in enclosures with partially thermally active side walls containing internal heat sources

Abstract

Unsteady laminar natural convection in an enclosure with partially thermally active side walls and internal heat generation is studied numerically. Thermally inactive parts of the side walls and horizontal walls are thermally insulated. The governing equations are solved using the control volume method with a power law scheme. Nine different combinations of the hot and cold thermally active zones are considered. The effects of heat generations, aspect ratios, different Prandtl numbers, and locations of the thermally active part of the side walls on the flow pattern (streamlines), heat distribution (isotherms), midheight velocity, and rate of heat transfer from the walls of the enclosure are presented. It is observed that the heat transfer rate increases with increasing the Grashof number due to an increase in buoyancy force and decreases with an increase in heat generation. The heat transfer is found to be the maximum when the hot and cold thermally active locations are placed at the middle of the side walls.