RADCAL: A Narrow-Band Model for Radiation Calculations in a Combustion Environment.
RADCAL: A Narrow-Band Model for Radiation Calculations
in a Combustion Environment.
Grosshandler, W. L.
NIST TN 1402; 52 p. April 1993.
Available from: National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
1-800-553-6847 or 703-605-6000;
Order number: PB93-200889
models; radiation; combustion; radiative heat transfer;
spectra; spectral absorptivity; spectral emissivity
Radiation within a medium containing products of
combustion is dependent upon the temperature and
concentrations throughout the entire field. The energy
is distributed across the infrared spectrum in a highly
nonlinear fashion, which greatly complicates modeling of
the heat transfer within a burning environment. This
report describes a numerical program, RADCAL, which
predicts the radiant intensity leaving a nonisothermal
volume containing nonuniform levels of carbon dioxide,
water vapor, methane, carbon monoxide, nitrogen, oxygen,
and soot. The absorption coefficient of the combined
gases is calculated from a narrow-band model and a
combination of tabulated spectral properties and
theoretical approximations to the vibrational-rotational
molecular bands. Soot is treated as a purely absorbing
substance in the Rayleigh limit. Background on the
development of the model, example calculations, and an
explanation of input procedures are presented.