Review article: Effect of ethanol-gasoline fuel blends on the exhaust emissions and characteristics of SI engines

Abstract

The stricter worldwide emission legislation and growing demands for lower fuel consumption and anthropogenic CO, NOx and HC emissions require significant efforts to improve combustion efficiency of SI engines while satisfying the emission quality demands. In this review, different volume % of ethanol fuel combined with gasoline provide particularly promising and at the same time, a challenging approach. Ethanol is widely used as an alternative fuel or an effective additive of gasoline due to the advantage of its high-octane number and it self-sustaining concept, which can be supplied regardless of the fossil fuel for the contribution of its faster flame speed, leading to enhanced combustion initiation and stability and improved engine efficiency. As a result, numerous studies have been carried out to study its effects on engine performance and emission. Nearly all published engine experimental results showed a significant improvement in combustion characteristics and enhanced engine performance for the use of ethanol-gasoline blend as fuel. Moreover, carbon monoxide and oxides of nitrogen emissions were also significantly decreased. The objective of this paper is to provide latest fuel blend technique through literature review and their effects on the emission and performance of SI engines.