Experimental investigation of fusel oil (isoamyl alcohol) and diesel blends in a CI engine

•Combustion, performance and emission characteristics of fusel oil-diesel blends.•Higher CPmax and HRRmax with the presence of fusel oil.•The lowest BSFC and the highest BTE were found for F0 test fuel.•CO and NOx emissions significantly reduced but HC increased with the addition of fusel oil.•Probably high moisture content of fusel oil absorbed the combustion temperature and provided low NOx emission. The present paper details an experimental investigation of the combustion behaviours, exhaust emission and performance characteristics of a single-cylinder diesel engine fueled with fusel oil-diesel blends of volumetrically 10%, 15% and 20% into neat diesel fuel (F0) separately. Under steady-state conditions, the tests were performed at constant engine speed (2000 rpm), and four different engine loads (2.5, 5, 7.5 and 10 Nm). The results showed that CO and NOx emissions significantly reduced down to 52% and 20%, respectively with an increasing percentage of the fusel oil in the fusel oil-diesel blends. However, HC gradually increased up to 40% with the addition of fusel oil. With respect to the performance of the engine, the lowest BSFC and the highest BTE were seen in F0 test fuel owing to the higher heating value of F0. On the other hand, duration in ignition delay (ID) of fusel oil-diesel blends was longer than that of F0 due to the lower cetane number of the fusel oil. The maximum in-cylinder pressure (CPmax) and maximum heat release rates (HRRmax) of fusel oil containing fuels is higher in comparison with diesel fuel owing to the longer ID and oxygen atoms of excessive fusel oil. The combustion characteristics of fusel oil-diesel blends closely followed those of neat diesel fuel.