The oxidation and ignition of dimethylether from low to high temperature (500–1600 K): Experiments and kinetic modeling

The oxidation of dimethylether (DME) has been studied in a fused silica jet-stirred reactor (JSR) at 10 atm, 0.2≤φ≤1, 550–1100 K. Concentration profiles of reactants, intermediates, and products of the oxidation were measured by low-pressure sonic probe sampling and off-line gas chromatography analyses. The results obtained in the cool flame regime are the first to be reported. The ignition delays of DME/O2/Ar mixtures have been measured in a shock tube at 1200 to 1600 K, at 3.5 atm and 0.5≤φ≤2. A numerical model consisting of a detailed kinetic reaction mechanism with 331 reactions (most of them reversible) among 55 species is proposed to describe both the low and high-temperature oxidation of DME in the JSR (550–1275 K, 1–10 atm) and the ignition of DME in shock tubes from low to high temperature (650–1600 K, 3.5–40 bar). A general good agreement between the data and the model was observed. A kinetic analysis involving sensitivity and reaction path analysis is used to interpret the results.

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