Technical Paper
Autoignition of Dimethyl Ether and Dimethoxy Methane Sprays at High Pressures
1997-05-01
971677
Recent studies suggest that the use of ethers as fuels or fuel additives may be a key to the simultaneous reduction of both particulate and NOx emissions from Diesel engines. The present study is directed towards understanding the chemical kinetics of autoignition of ethers under Diesel-like conditions. Autoignition experiments were performed in a constant volume apparatus (CVA), that allowed independent control of temperature, pressure, and oxidizing gas composition. Hollow cone sprays of methanol, dimethyl ether (DME), CH3OCH3, and dimethoxy methane (DMM), CH3OCH2OCH3, were created in quiescent air with a standard Diesel injector, and autoignition delays were inferred from pressure-time histories. A detailed chemical kinetic mechanism was developed to describe the pyrolysis, oxidation, and autoignition of methanol, DME and DMM at high pressures. The mechanism predicts autoignition delay time under Diesel-like conditions.
