A PARAMETRIC STUDY OF RADIATIVE HEAT TRANSFER IN AN INDUSTRIAL COMBUSTOR OF WOOD CARBONIZATION FUMES

ABSTRACT

Radiative heat transfer is investigated numerically for an industrial combustor of wood carbonization fumes. The combustor has a complex geometry. The finite–volume method (FVM) is applied to study radiative heat transfer in conjunction with the weighted sum of gray gases (WSGG) model of Kim and Song as a non-gray-gas model. The blocked-off-region procedure is applied to treat the geometric irregularities. The reliability of this model, for a complex geometry filled with a semitransparent medium and a regular geometry containing water vapor, is analyzed by comparing its predictions with the exact solution and the Monte Carlo technique associated with the statistical narrow band (SNB) model. Good agreement with benchmarks is found. The extension of this model to a mixture of CO₂, H₂O, particles, and soot particles (confined in a complex geometry) is made. The effects of soot volume fraction, partial pressure ratio, particle concentration, and thermal nonequilibrium on the inner wall radiative heat flux of the combustor are presented.