Effects of Ethanol-Gasoline Blends on Exhaust and Noise Emissions from 4-Stroke S.I.Engine

Abstract

Considering pollution problems and energy crisis today, investigationshave been concentrated on lowering the concentration of toxic components incombustion products and decreasing fuel consumption by using renewablealternative fuels. In the present work, the effect of ethanol addition to gasoline onthe exhaust emissions and noise level has been experimentally investigated atvarious engine loads.Results of the engine test indicated that using ethanol-gasoline blended fuelsincreases the power output of the engine dramatically (up to 50 %). While the COand HC emissions decrease as a result of the leaning effect caused by the ethanoladdition; and the CO2 emission increases because of the improvement ofcombustion. Also, it was noted that the noise level emission increases slightly withthe increase of ethanol content. Finally, the results showed that ethanol can be usedas a supplementary fuel to gasoline in modern spark ignition engines without majorchanges, and it can help to save our environment from toxic pollutants and to savea considerable part of the available oil.