Combustion characteristics and hydrocarbon emissions of a spark ignition engine fuelled with gasoline-oxygenate blends

Combustion characteristics and hydrocarbon emissions in a spark ignition en gine operating on oxygenated fuel blends are studied, and the mass fraction burned and engine hydrocarbon emissions are analysed. Calculation results, based on the recorded pressure diagram, show that the flame development an d rapid burn angles of gasoline-ether blends generally decrease and the max imum cylinder pressure increases as compared with those of gasoline. The fl ame development angle and rapid burn angle decrease when the fraction of al cohol fuels in gasoline is small, whereas they increase when the fraction o f alcohol fuels is large. The experimental results show that engine exhaust hydrocarbon emissions can be reduced by blending oxygenated fuels in gasol ine rather than operating on neat gasoline. Operating on gasoline-ether ble nds rather than on gasoline-alcohol fuel blends and neat gasoline greatly r educes hydrocarbon emissions.