Abstract：The mechanism of methane/dimethyl ether chemical reaction was reduced by genetic algorithm, which could effectively enhance the calculation speed and decrease the calculation cost meanwhile ensuring the calculation accuracy. Twenty-four target conditions were selected to guide the homogeneous ignition calculation, and the ignition delay time and steady-state temperature were used as the optimization indexes to guide the genetic algorithm to ensure that the final simplified mechanism can comprehensively and reliably describe the combustion characteristics of the methane/dimethyl ether fuel mixture. The simplified mechanism consists of 45 species and 119 reaction steps, and its ignition delay time has a maximum error of no more than 4.5% with respect to the original mechanism. The validity of the simplified mechanism was also verified by the measured data using surge tubes and laminar flow flames. Meanwhile, in the methane/dimethyl ether high-pressure turbulent combustion numerical calculation, the simplified mechanism maintains good agreement with the detailed mechanism in terms of temperature field, free radicals, end product trends and numerical magnitude, while reducing the computation time by nearly 30%. The simplified mechanism achieves a good balance between computational accuracy and computational cost, and facilitates numerical simulation of large-scale batch combustion.
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