A WIDE-RANGE MODELING STUDY OF DIMETHYL ETHER OXIDATION

A detailed chemical kinetic model has been used to study dimethyl ethe r (DME) oxidation over a wide range of conditions. Experimental result s obtained in a jet-stirred reactor (JSR) at 1 and 10 atm, 0.2 less th an or equal to phi less than or equal to 2.5, and 800 less than or equ al to T less than or equal to 1300 K were modeled, in addition to thos e generated in a shock tube at 13 and 40 bar, phi = 1.0 and 650 less t han 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 kineti c model severely, as it must be able to predict the correct distributi on and concentrations of intermediate and final products formed in the oxidation process. Additionally, the shock-tube results are very usef ul, as they were taken at low temperatures and at high pressures, and thus undergo negative temperature dependence (NTC) behavior. This beha vior 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 specie s and 336 chemical reactions. The thermodynamic properties of unknown species pertaining to DME oxidation were calculated using THERM. (C) 1 998 John Wiley & Sons, Inc.