Dynamical analysis of methanol-dimethyl ether autoignition at engine-relevant conditions

We have computationally investigated the auto-ignition of a methanol-air mixture with the addition of dimethyl ether at a high pressure and low-temperature environment aiming at its utilization to HCCI engines. It is found that the addition of dimethyl ether substantially reduced the ignition delay of the methanol-air mixture. This is caused by the inclusion of a specific chemical species and reaction of the dimethyl ether combustion. Comprehensive understanding of chemical pathways, as well as the important species and reactions, have been identified with the help of tools derived from the computational singular perturbation method.