Flame radiation

Flame radiation is generally recognized as an important factor in fire phenomena and many combustion systems. Accurate prediction of flame radiation requires a good understanding of the radiative transport theory as well as detailed information on the radiative properties of the combustion products which generally consist of a mixture of gases plus soot particles. In this article the physics of gas radiation and its application to non-luminous flame calculations are first introduced. Subsequent formulation of luminous flame radiation incorporates properly the continuous soot emission. Effects of non-homogeneous distributions of temperature and gas partial pressures along the pathlength are discussed for both luminous and non-luminous flames. For engineering applications, useful radiation quantities such as the total emissivity, the mean absorption coefficient, and the radiation conductivity are expressed in simple analytical representations in terms of pertinent flame parameters.