Diesel emission improvements by the use of oxygenated DME/diesel blend fuels

摘要

A kind of oxygenate fuel, DME, has been proposed and tested for use with diesel fuel as a means of reducing exhaust emissions. The addition of DME to diesel fuel results in the decrease of the lower calorific value, aromatics fraction and kinematic viscosity of blend fuels. Simultaneously, cetane number, C/H ratio and oxygen content of the blends are enhanced, which has some favorable effects on the combustion and emission of the blends with 10%, 20% and 30% DME by mass. The study on the performance and emissions of the diesel/DME blend is conducted in a DI engine. The emission characteristics of four fuels are determined in a diesel engine. At high loads, the blends reduce smoke significantly with a little penalty on CO and HC emissions compared to diesel fuel. NO_x and CO_2 emissions of the blends are decreased somewhat. At low loads, the blends have slight effects on smoke reduction due to overall leaner mixture. The results indicate the potential of diesel reformation for clean combustion in diesel engines.