3-DIMENSIONAL NON-GREY GAS RADIATIVE-TRANSFER ANALYSES USING THE STATISTICAL NARROW-BAND MODEL

Three-dimensional non-grey gas radiation analyses were conducted using the statistical narrow-band model with updated band parameters and th ree implementation methods: the exact or the correlated formulation, t he non-correlated expression, and the grey-band approximation with the absorption coefficient estimated using the local properties. The accu racy of the two approximate narrow-band implementation methods was eva luated for both low-resolution spectral intensity and spectrally integ rated radiative source term and wall heat flux in a rectangular enclos ure containing (1) isothermal pure water and (2) a CO2/H2O/N-2 mixture with a furnace type gas temperature distribution. For spectrally inte grated quantities, results of the grey-band approximation are very clo se to those of the non-correlated formulation and are in qualitative a greement with the results of the correlated formulation. The two appro ximate methods are capable of predicting qualitatively correct and fai rly accurate distributions of low-resolution spectral radiation intens ities for the isothermal case. However, they predict less accurate low -resolution spectral intensities for the non-isothermal case. (C) Else vier, Paris.