4. Glossary

The following definitions are taken from the Groupement Français de Combustion (GFC).

Flame; flame

In the broadest sense, the space-time structure in which live combustion takes place, generally with a high concentration of radicals, an excited fraction of which may emit radiation (chemiluminescence). Some radicals with low recombination rates (OH) may persist by diffusion beyond the flame front into the burnt gases. A flame is a gaseous reaction medium (liquids and solids generally need to be gasified before burning) of limited volume and high energy, where chemical reactions, diffusion of chemical species and heat, and light emissions occur and mutually support each other.

Flame structure; flame structure

Distribution of flame parameter values: shape, thickness, orientation, composition,...