Effect of molecular additives on ignition of a methane-air mixture

The ignition of a methane-air mixture with additives of $\mathrm{ClF}_5$, $\mathrm{ClF}_3$, $\mathrm{OF}_2$, and $\mathrm{H}_2\mathrm{O}_2$ (additive content in the mixture $\le 1\%$) is studied by numerical simulation. The ignition temperature of the mixture is determined as a function of the initial pressure and additive content. It is shown that the introduction of additives into the mixture leads to a significant decrease in the ignition temperature due to the acceleration of the formation of active particles and intensification of the chain mechanism of the process. Of the additives considered, chlorine pentafluoride is the most effective additive, and hydrogen peroxide is the least effective one.