Inhibition of various hydrogen combustion regimes in air by propylene and isopropanol

This paper studies the effects of small additives of propylene and isopropanol on the hydrogen-air flame speed in the predetonation regime, deflagration-to-detonation transition, and burning rate. It is shown that the difference in the effects of these additives on the combustion is determined primarily by their ability to terminate reaction chains. In hydrogen flames, the additives are consumed as a result of their reactions with the active intermediate products of H$_2$ combustion in which these species are replaced by inactive radicals.