DefinePK

Abstract

The use of oxygenated bio-fuels like bio diesel and ethanol in combination with diesel is an effective measure to substitute renewable fuels and reduce particulate matter (PM) from in-use diesel vehicles. To study the fuel performance, three oxygenated blend fuel designs containing volumes of 15% ethanol with cetane improver additive, 10% ethanol with 10% bio diesel and 15% ethanol with 20% bio diesel were formed. The physical stability of ethanol diesel blend is studied and phase separation is prevented by adding co solvents like Tetrahydrafuran and bio diesel. To meet stricter emission norms, now diesel engines are fitted with after treatment devices. This paper describes the engine and emission characteristics of the above blend fuels on a 4 cylinder, naturally aspirated light duty diesel engine fitted with diesel oxidation catalyst. The engine test results show that it is feasible to use these blends in diesel engines: the thermal efficiencies of the engine fueled by the blends are comparable with that fueled by diesel, with small increase in fuel consumption, due to the lower heating value of ethanol and bio diesel. The smoke emissions from the engine fueled by the blends are lower than that fueled by diesel owing to the increased oxygen content. The reduction is more at higher loads. The HC and CO emissions are found to be higher at lower loads due to the lower cetane number of ethanol. However, NO emissions depend on load conditions and blend contents.