Buoyancy-dominated laminar convection and radiation transfer in rod arrays

Laminar combined free and forced convection together with radiation transfer in flow of steam at 68 bar through rods in triangular and square arrays have been investigated numerically. The pitch to diameter ratio has been varied from 1.2 to 2.0. Heat transfer results have been obtained for both up and down forced flow influenced by bouyancy with and without the effects of variable thermophysical fluid properties. The Rosseland diffusion approximation has been used for radiative transfer. First- and second-orde r density changes have been investigated.