Performance of Microemulsion Fuels As an Alternative for Diesel Engine

Microemulsions are sustainable alternatives to fos sil fuels, which could possibly be used without any modifications in current engines and storage-transportation-supply infrastructure. Our current work attempts to examine the usability of butanol-diesel-water microemulsion fuels in a diesel engine. A small percentage of water is desirable, as it reduces the NOx and smoke emissions. The microemulsion regions were mapped out in ternary phase diagrams, and the fuel was characterized as per ASTM D975, and further examined for its performance in a diesel engine. The formulated microemulsions satisfied the ASTM standards, and had properties (density, viscosity, flash points, cloud points, copper strip corrosion rating, sulfur content, and ash percent) close to those of neat diesel. The percentage change in property ε was calculated as [|(εdiesel − εmicroemulsion)|/εdiesel] × 100. The calorific values for the microemulsion fuels showed a maximum reduction of 8.31% as compared to that of neat diesel. The brake thermal efficiency, however, increased by 15.38% for the same, with respect to the value for neat diesel (2% higher overall efficiency of the engine). The brake specific fuel consumption was also lowered by 5.04%, and the maximum reduction in emissions of CO, unburnt HC, CO2, and NOx were observed to be 53.48%, 67.40%, 30.82%, and 41.72%, respectively, relative to those of neat diesel. The present experimental investigations thus suggest that the microemulsions could be used as a sustainable cleaner alternative to diesel.