Performance and emissions of DI compression ignition engines fueled with dimethyl ether (Performance and emissions in retrofitted engines)

Engine performance and exhaust gas characteristics of a direct injection CI engine were investigated with neat dimethyl-ether (DME), an alternative fu el being considered for attaining low emissions. The study was conducted by comparing the new fuel with the conventional diesel fuel. Results from the present work include: ( 1) It was necessary to add a small amount of lubri cating additives to DME in order to achieve satisfactory engine operation, to minimize excessive wear in the injection nozzle. (2) Engine performance for both fuels was mutually comparable. (3) Although negligible amounts of soot and very low THC emissions were measured, NOx emission was about the s ame as in diesel fuel operation. (4) The reduction of NOx emission by retar ding the injection timing was highly significant with DME. (5) The NOx emis sion from the retrofitted engine could be further reduced by dissolving CO2 in DME.