Effect of ethanol-gasoline blends on SI engine performance and emissions

Negative effects of using traditional engine fuels on climate change and global warning have produced a scenario of high competition to find an alternative fuel more friendly and unharmful to the environment. Alcohol fuel was found very practical to be mixed with engine designed fuel. In the present work, ethanol was mixed with gasoline in different proportions (10% ethanol + 90% gasoline, 20% ethanol + 80% gasoline, 30% ethanol +70% gasoline, 40% ethanol + 60% gasoline) by utilizing ultrasonic bath to ensure perfect mixing which in turn will increase the fuel energy content. A one-cylinder, four-stroke and spark ignition engine was used to study and analyze the effect of ethanol's/gasoline blend on power, efficiency and exhaust gases. Results showed that power, brake specific fuel consumption and thermal efficiency are improved with the increase of ethanol concentration. On the other hand, ethanol was found to have negative effect on volumetric efficiency. Furthermore, adding ethanol reduce harmful exhaust gasses. It is found that more ethanol is an accompanied with less exhaust gasses. Finally, research octane number and motor octane number are found to be much with ethanol blends. Although lower heating value was found to be higher for pure gasoline, it's found that all other parameters are enhanced with adding ethanol to the engine fuel.