Comparison of Experimental and Computed Species Concentration and Temperature Profiles in Laminar, Two-Dimensional Methane/Air Diffusion Flames.
Comparison of Experimental and Computed Species
Concentration and Temperature Profiles in Laminar,
Two-Dimensional Methane/Air Diffusion Flames.
(2223 K)
Norton, T. S.; Smyth, K. C.; Miller, J. H.; Smooke, M.
D.
Combustion Science and Technology, Vol. 90, No. 1-4,
1-34, 1993.
Keywords:
laminar flames; diffusion flames; species
concentrations; temperature profiles; flame structure;
radicals; scalar dissipation
Abstract:
Experimental concentration measurements of the major
stable species and five radical species (OH, H atom, O
atom CH, and CH3) obtained on a rectangular
Wolfhard-Parker slot burner are compared with a detailed
computation of the chemical structure of an axisymmetric
laminar, CH4/air diffusion flame burning at atmospheric
pressure. In order to examine these CH4/air flames with
different geometries and different sizes, the species
profiles are plotted as functions of the local mixture
fraction, and the scalar dissipation rate has been
matched in a region around the stoichiometric surface.
The overall agreement in the absolute concentrations,
the shape of the profiles, and their location in terms
of the local mixture fraction is good to excellent for
the stable species (except for O2) and for the most
abundant radicals OH, H atom, and O atom. For example,
the calculated OH maximum concentration is in much
better agreement with the experimental results than are
full equilibrium and partial equilibrium estimates.
Less satisfactory agreement is found for the CH and CH3
radicals. In addition, significant discrepancies are
observed in the temperature field and in the degree of
O2 penetration into rich flame regions.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899