Theoretical and Experimental Researches Regard the Use of Bioethanol at the Supercharged Spark Ignition Engine

Abstract

The use of bioethanol as alternative fuel for automotive supercharged spark ignition engines is required especially for to respect the pollutant norms which become more and more severe, especially for NOx emissions.The general objective of the researches is improving of a automotive supercharged spark ignition engine efficiency, improving performance of power and torque and decreasing of the emissions level by the use of bioethanol. Bioethanol is so a very good alternative fuel for SI engines because of its better combustion proprieties comparative to the gasoline as a good cooling agent of the intake air due to its high vaporization heat.The paper presents results of some theoretical and experimental investigations on a 1.5 L supercharged SI engine fuelled with gasoline-bioethanol blends. The investigations show that the improvement of the combustion process by use the bioethanol at the supercharged spark ignition engine leads to the reduction of BSFC, to the accentuated reduction CO and HC due to a lower C content and better combustion properties of the bioethanol. In same time, the NOx emissions level significantly decreases because of the local cooling effect produced by bioethanol vaporization.