Autoignition mechanism of dimethyl ether–air mixtures in the presence of atomic iron

The need to find reactive additives capable of reducing the combustibility of dimethyl ether is an important problem in connection with the widening use of ether as an environmentally friendly alternative motor fuel. In this study, the autoignition chemistry of mixtures of dimethyl ether with air in the presence of atomic iron was investigated by numerical methods. Atomic iron, which is an effective inhibitor of premixed laminar hydrocarbon flame was found to shorten the induction period. However, the additive affects only the first stage of the induction period. The mechanism promoting the low-temperature oxidation of dimethyl ether–air mixture by atomic iron involves the formation of hydroxyls in reactions involving iron compounds. Since the additive hardly changes the duration of the second stage of the induction period, it can be suggested that OH radicals play an insignificant role in the low-temperature oxidation of dimethyl ether at this stage.