Role of atomic hydrogen diffusion in a hydrogen flame
A numerical modeling study of the propagation of a laminar flat homogeneous gas flame has shown that in a hydrogen-air flame,
a rapid increase in the concentration of OH radicals begins in the range of low temperatures and the concentration profile
has two maxima. The first maximum in the low-temperature region of the front is related to the diffusion of H atoms, formation
of HO2 radicals, and the quadratic branching reaction H + HO2 → OH + OH. The second maximum in the OH concentration profile is due to the classical high-temperature branching reactions
H + O2 → OH + O and O + H2 → OH + H.