The effects of using ethanol as additive on the combustion and emissions of a direct injection diesel engine fuelled with neat lemongrass oil-diesel fuel blend

In this experimental work, ethanol was mixed with neat lemongrass oil (LGO) - diesel fuel blend and the effect of ethanol concentration on combustion, emission, and performance of direct injection diesel engine was investigated. Low concentrations of ethanol (2.5% and 5%) were studied in the blend of neat lemongrass oil-diesel blend. The test results obtained with these blends were compared with those obtained with diesel fuel. The tested blends yielded different performance, emission and combustion characteristics compared to diesel fuel. The ethanol blends resulted in a higher combustion pressure and heat release rate, brake specific fuel consumption and brake thermal efficiency than diesel and LGO25(75% neat diesel + 25% neat lemongrass oil) while they resulted in a higher NOx emission, CO2 emission and lower smoke, HC emissions. Further, it is observed that higher combustion duration and ignition delay period for LGO25-ethanol blends than neat diesel and LGO25 fuels.