F. Liu et al., NON-GREY GAS RADIATIVE-TRANSFER ANALYSES USING STATISTICAL NARROW-BAND MODEL, International journal of heat and mass transfer, 41(14), 1998, pp. 2227-2236
Nongrey gas radiation analyses were conducted using the statistical na
rrow-band model and four implementation methods: the exact or the corr
elated formulation, the noncorrelated expression, grey-band approximat
ion based on global absorption coefficient, and a new approximate meth
od. The new method is also a grey-band approximation but utilizes the
local absorption coefficient. Using results of the correlated formulat
ion as benchmark solution, accuracy of the three approximate narrow-ba
nd implementation methods was investigated for several one-dimensional
non-grey gas radiation problems in parallel plate enclosure containin
g radiating gases of both uniform and non-uniform temperatures and/or
concentrations. Radiative source term and wall heat flux predicted by
the noncorrelated expression and the new method are in very close agre
ement with each other and in fair to good agreement to benchmark solut
ions. Radiative source term calculated from the grey-band approximatio
n based on global absorption coefficient is in serious error. CPU time
saving of two orders of magnitude can be achieved by using the three
approximate implementation methods, relative to the correlated formula
tion. The new method provides slightly better accuracy than the noncor
related approach with additional advantages that an arbitrary solution
method can be employed and less CPU-time is required. (C) 1998 Nation
al Research Council of Canada. Published by Elsevier Science Ltd. All
rights reserved.