A wide range modeling study of dimethyl ether oxidation

A detailed chemical kinetic model has been used to study dimethyl ether (DME) oxidation over a wide range of conditions. Experimental results obtained in a jet-stirred reactor (JSR) at 1 and 10 atm, 0.2 less than or equal to phi less than or equal to 2.5, and 800 less than or equal to T less than or equal to 1300 K were modeled, in addition to those generated in a shock tube at 13 and 40 bar, phi = 1.0 and 650 less than or equal to T 1300 K. The JSR results are particularly valuable as they include concentration profiles of reactants, intermediates, and products pertinent to the oxidation of DME. These data test the kinetic model severely, as it must be able to predict the correct distribution and concentrations of intermediate and final products formed in the oxidation process. Additionally, the shock-tube results are very useful, as they were taken at low temperatures and at high pressures, and thus undergo negative temperature dependence (NTC) behavior. This behavior is characteristic of the oxidation of saturated hydrocarbon fuels, (e.g., the primary reference fuels, n-heptane and iso-octane) under similar conditions. The numerical model consists of 78 chemical species and 336 chemical reactions. The thermodynamic properties of unknown species pertaining to DME oxidation were calculated using THERM. (C) 1998 John Wiley & Sons, Inc.