Impact of Petrol-Ethanol Blending Ratios on the Performance and Combustion Efficiency of Spark Ignition Engines

Abstract

Alternative fuels are expected to play an important role in future developments of spark ignition engines, the main reason being the need to reduce dependence on fossil fuels due to its harmful environmental impact. This study aims to analyse the performance of gasoline-ethanol fuel blends on a four stroke spark ignition engine test bed and compare the performance with that of pure gasoline. Different blend ratios (by volume); E3 (3% ethanol and 97% gasoline), E6 (6% ethanol and 94% gasoline), E9 (9% ethanol and 91% gasoline) and E12 (12% ethanol and 88% gasoline) were studied in this work. The test was conducted on a TQ small engine test bed located in the University of Benin. Engine performance calculations were used in determining the brake power, torque, specific fuel consumption and efficiencies of the engine when the different fuel blends were used. The various results obtained were compared to that of pure gasoline, E0 (0% ethanol and 100% gasoline) the base/control fuel. The results obtained showed noticeable increase in the break power, torque and thermal efficiency compared to that of pure gasoline. However, there was also a noticeable slight increase in the specific fuel consumption of the engine. Finally, of all the tested samples, E12 blend gave a better overall performance when compared to the control fuel