Zeldovich mechanism
Zel'dovich mechanism is a chemical mechanism that describes the oxidation of nitrogen and NOx formation, first proposed by the Russian physicist Yakov Borisovich Zel'dovich in 1946. The reaction mechanisms read as
where and are the reaction rate constants in Arrhenius law. The overall global reaction is given by
The overall reaction rate is mostly governed by the first reaction, since the second reaction is much faster than the first reaction and occurs immediately following the first reaction. At fuel-rich conditions, due to lack of oxygen, reaction 2 becomes weak, hence, a third reaction is included in the mechanism, also known as extended Zel'dovich mechanism,
The forward rate constants of the reactions are given by
where the pre-exponential factor is measured in units of cm, mol, s and K, temperature in kelvins, and the activation energy in cal/mol; R is the universal gas constant.NO formation
The rate of NO concentration increase is given byN formation
Similarly, the rate of N concentration increase is
