The gas composition was devived using the theory of gas ionization after hydrogen-air mixed gas ionization. The catalysis effect of active group on combustion rate and intensity was found out with the theoretical analysis

and the influences on deflagration to detonation transition (DDT) process in different ignition energies and different concentrations of active group were analyzed. Fully considering the hydrogen-air combustion reaction 23-step kinetics mechanism

the the numerical simulation method was used to study DDT process in different cases by FLUENT

and the theoretical analysis was verified. Results show that when the ignition temperature is in the range of 2000-2500K

the reactive group in the process of ignition can increase the combustion rate; DDT time can be shortened by 9.91%-21.08%

and DDT distance can be shortened by 3.32%-8.08%. With increase of the ignition temperature

DDT time and DDT distance increase. Gas ionization effect should be considered if ignition energy is high.