RADCAL: A Narrow-Band Model for Radiation Calculations in a Combustion Environment.
RADCAL: A Narrow-Band Model for Radiation Calculations
in a Combustion Environment.
(2748 K)
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.
Telephone:
1-800-553-6847 or 703-605-6000;
Fax: 703-605-6900.
Website: http://www.ntis.gov
Order number: PB93-200889
Keywords:
models; radiation; combustion; radiative heat transfer;
spectra; spectral absorptivity; spectral emissivity
Abstract:
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.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899