Combined conductive and radiative heat transfer in a thermally developing t
wo-phase Poiseuille flow in a cylindrical duct is studied here. A two-phase
radiative transfer equation (RTE) considering radiation by both gas and pa
rticles is taken into account. A complex form of nonlinear integrodifferent
ial RTE is solved by the discrete ordinates method (DOM, or so called S-N m
ethod) in axisymmetric geometry. After such validation, namely, the solutio
n in a two-dimensional channel flow between two flat plates is compared wit
h that solved by the zone method, the program is then applied to fully deve
loped gas-particle two-phase flow in a cylindrical duct. A parametric study
is performed for gas and particle absorption coefficients, particle number
density, particle emissivity, and wad emissivity. The results show a signi
ficant effect of two-phase radiation on the thermal characteristics. Howeve
r, in all cases, it was found that conduction is predominant near the wall.