RADIATIVE ENHANCEMENT OF HEAT TRANSFER TO A GRAY GAS THROUGH PARTICLE SEEDING

Abstract

Combined effects of radiation and convection are examined in turbulent flow of gray gases, dispersely seeded with absorbing, emitting, scattering particles. Seeding particles are used as a heat transfer enhancement technique, whereby radiatively participating particles receive radiation from hot tube walls, and transfer this heat to the gas. It is found that enhanced heating of the gas is only achieved for low gas optical thicknesses and when the seeding particles are small and either hollow or of low material density. Enhancements are identified for both radiation-dominated and combined mode (radiation / convection) cases, as functions of dimensionless parameters.