Exact and mean beam length calculations for radiative heat transfer in gases
Abstract
This note examines the validity of the mean length technique, which is an approximate engineering method for calculating radiative heat transfer in furnace gases. Exact and mean beam length results are compared for laminar flow of carbon monoxide between parallel black surfaces. The results show that the mean beam length calculations overestimate the heat transfer by 47 per cent. The approximation gives better results than other approximate techniques used such as the gray gas and optically thin approximations. Further work is needed to determine the validity of the mean beam length technique in more complicated geometries, and when gas mixtures are present.
 Publication:

Combustion Science and Technology
 Pub Date:
 1974
 Bibcode:
 1974CST.....9..273M
 Keywords:

 Beams (Radiation);
 Carbon Monoxide;
 Gas Flow;
 Laminar Flow;
 Radiative Heat Transfer;
 Combustion Products;
 Emissivity;
 Furnaces;
 Parallel Plates;
 Wall Flow;
 Fluid Mechanics and Heat Transfer