Mechanism of combustion reactions in hydrogen-air premixed flames

Simulation was conducted using a chemical kinetic model built for flat H₂-air premixed flames to study the combustion mechanism occurring in flames through a wide range of equivalence ratio. The data showed that the flame zone of the stoichiometric flame can be considered as having two different regions. The low temperature region had, furthermore, three parts differing in reaction mechanism. Also, since reactions could not proliferate hydrogen atoms by themselves in the low-temperature region, the acceleration of the reactions is necessarily governed by the hydrogen atoms diffused from the flame front. Meanwhile, in the high temperature region, the reactions produced an excess of hydrogen atoms, which activate the reactions in this region or diffuse toward the low temperature region. Leah hydrogen flames possess small burning velocity than that of rich flames since the reactions in the low temperature region have less reproducibility of hydrogen atoms.