Numerical simulation of coupled heat transfers by conduction, natural convection and radiation in hollow structures heated from below or above

Coupled heat transfers in hollow structures uniformly heated from below or from above are numerically investigated. Discussions of the results are for structures formed by a range of 3 identical rectangular cavities with end vertical side walls of the structure assumed adiabatic or submitted to periodic conditions. The Boussinesq approximation is invoked and the flows are considered laminar and two-dimensional for the whole range of parameters considered. Conduction heat transfer in the solid partitions and surface radiation amongst grey diffuse surfaces are accounted for. The conservation equations are solved by a finite difference method and the pressure–velocity coupling solved by the SIMPLE algorithm.