Numerical analysis of combustion kinetics for hydrogen–air mixtures with NH$_3$, CH$_4$, and C$_2$Н$_6$

The possibility of reducing the concentration of nitrogen oxides and HNO$_x$-group components with simultaneous shortening of the reaction-zone length during combustion of hydrogen-air mixtures in a supersonic flow behind an oblique shock wave by introducing NH$_3$, CH$_4$, and C$_2$Н$_6$ additives into the mixture is analyzed. A numerical study shows that a small (up to 5%) amount of these additives substantially changes the combustion kinetics behind the shock-wave front, shortens the flame length, and diminishes the NO and NO$_2$ content in the combustion products.