Investigation on the gaseous and particulate emissions of a compression ignition engine fueled with diesel–dimethyl carbonate blends

The effect of dimethyl carbonate (DMC) on the gaseous and particulate emissions of a diesel engine was investigated using Euro V diesel fuel blended with different proportions of DMC. Combustion analysis shows that, with the blended fuel, the ignition delay and the heat release rate in the premixed combustion phase increase, while the total combustion duration and the fuel consumed in the diffusion combustion phase decrease. Compared with diesel fuel, with an increase of DMC in the blended fuel, the brake thermal efficiency is slightly improved but the brake specific fuel consumption increases. On the emission side, CO increases significantly at low engine load but decreases at high engine load while HC decreases slightly. NOx reduces slightly but the reduction is not statistically significant, while NO2 increases slightly. Particulate mass and number concentrations decrease upon using the blended fuel while the geometric mean diameter of the particles shifts towards smaller size. Overall speaking, diesel–DMC blends lead to significant improvement in particulate emissions while the impact on CO, HC and NOx emissions is small.

Research Highlights
► DMC could cause longer ignition delay and increase the fraction of fuel burned in the premixed combustion period whereas decrease slightly the total combustion duration and the amount of fuel consumed in the diffusion combustion period.
► DMC–diesel blends lead to slight increase in the brake thermal efficiency.
► DMC–diesel blends lead to significant improvement in particulate emissions.
► In general, DMC could increase CO and NO2 emissions, decrease HC emission while has small impact on NOx emission.