Research on hazardous effect of PETROL-ETHANOL blends emissions in spark ignition engines

This paper deals with ecological aspects of using alcohol fuels in spark ignition (SI) engines, determining ecological characteristics of SI engine for various fuels. The dependence of the emission of hazardous material-carbon monoxide (CO), hydrocarbons (HC), carbon dioxide (CO2) - on the number of crankshaft revolutions n, engine torque Me and the ignition advance angle teta was determined in the SI engine bench tests. The toxicity of the emission at idle running of the engine had been also measured. The purpose of the bench tests is to work out the characteristics of the partial speed, loading and regulation according to the ignition timing advance. The bench tests of SI engine were performed with the Pb-free petrol A-76 and its mixtures with ethanol ester-aldehyde fraction, using fusels as stabilizers. Aldehyde is a colourless liquid produced by oxidation of alcohol. Fusel is a colourless oily alcohol separated in the rectification of ordinary distilled alcohol. The test bench can estimate the torque Ms, when the revolutions of the crankshaft range from 83 s-1 to 314 s-1 (800-3000 rev/min.), therefore, ecological characteristics of exhaust gases can be determined. The impact of the temperature of the alcohol mixtures' exhaust gases that was lower by 20-30 centigrade C on their toxicity was investigated.