EFFECT OF RADIATIVE HEAT TRANSFER PROPERTIES ON COMBUSTION SIMULATION FOR PULVERIZED COAL EXPERIMENTAL FURNACE
Radiative transfer in a pulverized coal furnace (coal feed 6[kg/hr]) is studied. Pulverized coal combustion simulation is performed considering radiation transfer of particles for the furnace. The first order spherical harmonics approximation is used to model the radiative transfer equation. To confirm the accuracy of the simulated result the temperature and unburnt carbon profiles are measured and are compared. Parametrical analyses are employed to evaluate the influence of the particle emissivity on the combustion simulation. The influence of the radiation appeared particularly as differences of the ignition position and the relaxation of a temperature gradient around the flame zone because the preheat effect of coal particles near burner nozzle is enhanced by the absorption of radiation energy propagated from the combustion area. It is found that the accuracy of a pulverized coal combustion simulation especially in the ignition step depends on a radiation transfer property.