Autor/autori: Lect. Ph.D Eng. Alexandru CERNAT, Ph.D student Eng. ?tefan VELESCU

Abstract: The experimental investigation has the goal of determination of the influences on a single cylinder engine performances, mechanical running and pollution level for gasoline-bio-ethanol blends fuelling. The reference is establish for gasoline fuelling, E 0 and two other types of fuel were used E20 and E85. By its physical and chemical properties bio-ethanol influences the combustion process and finally the engine running, performance and pollutant emissions. It’s shows that the increase of bio-ethanol content in gasoline blends leads to the reduction of combustion duration due to a faster burning assured by bio-ethanol high flame velocity and increase in terms of power. Also, the maximum pressure values reached for E20 and E85 are significantly bigger comparative to E0 and the engine efficiency defined by BSFC is improved. On the aspects of chemical structure and combustion improvement, the pollutant emission, as CO and un-burn HC, are decreased for E20 and E85. Only the NOx emissions increase for E20 and E85 comparative to gasoline fuelling, E0, in similar percents with possibilities of decreasing by exhaust gases recirculation and catalytic converter use. All these parameters variation at E20 and E85 fuelling is presented for a wide area of air-fuel ratios from ? =0.85 till ? =1.3. Finally, the main conclusions of the study were formulated as a definition of the dosage values at which the efficiency and pollution level are improved.

Keywords: gasoline-bio-ethanol blends, flame velocity, maximum pressure, efficiency, pollutant emissions