Flammability limits of premixed and diffusion flames

Abstract

It is well known that not all fuel/oxidant/diluent mixtures can propagate flame. Normal flame-type combustion cannot be sustained outside certain limits definable in terms of fuel/oxidant/diluent composition. Definition of these limits has received a great deal of attention in premixed combustion conditions, that is, in systems where the fuel and oxidant are mixed prior to combustion. Despite scientific interest in the subject dating back to the nineteenth century, the mechanism responsible for flammable limits is not yet understood. Nonetheless, a great deal has been learned that has practical application