The low-temperature combustion kinetics of dimethyl ether (DME) were studied by means of stabilized cool flames in a heated stagnation plate burner configuration, using ozone-seeded premixed flows of DME/O 2 . Direct imaging of CH 2 O* chemiluminescence and Laser Induced Fluorescence of CH 2 O were used to determine flame front positions in a wide range of lean and ultra-lean equivalence ratios and ozone concentrations, for two strain rates. Temperature and species mole fraction profiles along the flame were measured coupling thermocouples, gas chromatography, micro-chromatography and quadrupole mass spectrometry analysis. A new kinetic model was built on the basis of the Aramco 1.3 model, coupled with a validated submechanism of O 3 chemistry, and was updated to improve the agreement with the obtained experimental results and experimental data available in the literature. Main results show the efficiency of the tested model to predict the flame front position and temperature in every tested condition, as well as the importance of reactions typical of atmospheric chemistry in the prediction of cool flame occurrence. The agreement on the fuel and major products is overall good, except for methanol, highlighting some missing kinetic pathways for the DME/O 2 /O 3 system, possibly linked to the direct addition of atomic oxygen on the fuel radical, modifying the products distribution after the cool flame.

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