Hydrous Ethanol-gasoline Blends as Alternative Fuels for Spark Ignition Engine: Fuel Properties and Engine Performance

The fuel characteristics of hydrous ethanol (HE) and gasoline blends (HE10, HE15 and HE20) were investigated as an alternative fuel for spark-ignition (SI) engines and test their performance. The densities of the blends (754.4-769.1 kg m-3) were higher than that of gasoline (739.7 kg m-3); however, their API gravity (55.88-52.3) was lower than that of gasoline (59.53). The kinematic viscosity of the blends (0.588 to 0.670 mm2 s-1) indicated that the blends were more viscous than gasoline (0.4872 mm2 s-1). Flashpoint values of the blends varied from 28.4 to 29.2?, which were higher than that of gasoline flashpoint value (25.0?); however, the calorific value of the blends (ranging between 45.21 and 45.08 MJ kg-1) was lower compared to that of gasoline (45.27 MJ kg-1). The Octane number of the blends varied from 92.9 to 95.8, which was higher compared to that of gasoline (90.5). At low engine speed (1500 rpm) and high load (2.5 kg), the engine torque obtained with gasoline was 10.7% higher than that obtained with the blends. However, at high engine speed (2500 rpm) and high load (3.2 kg), the torque with gasoline was only 2.7% higher than with the blends. Overall, HE15 blend showed the best results among the examined blends.