Effect Of Gasoline Property On The Emission Characteristics Of Gasoline Engine

The quality of gasoline is the guarantee of the high-quality emission of gasoline engines.It is important to understand the influence of fuel components on gasoline engines emission for the upgrading of oil quality and the development of gasoline standards.In order to explore the influence of gasoline composition on gasoline engine emissions,fuels with different components and characteristics were configured in this study.The experimental researches were conducted on a GDI &PFI engine under cold(35?)and hot(85?)conditions respectively including different speeds and loads of engines.And the effects of distillation characteristics and ethanol blending ratio gasoline on particle and gas emissions of gasoline engines were studied.Study indicated that:1.There is an obvious effect of gasoline distillation on the particle emissions of engines.The research shows that under the idle and cold conditions,the worse the volatility of the fuel,the higher the concentration of particle numbers.This is because the bad performance of fuel distillation results in a decrease in the concentration of the mixed gas under the same working conditions and the combustion quality deteriorated.Under hot condition,particle numbers becomes larger as the fuel distillation performance deteriorates except for the low-speed and large-load tested points.2.The effect of gasoline distillation characteristics on the gas emission of GDI+PFI engine is not obvious as the effect on particles.Under cold condition,the THC emission increases slightly with the increase of the fuel drive index,but the NOx emission tends to increase and then decrease with that.Moreover,the CO and NOx emissions showed a slight increase with the deterioration of the fuel distillation characteristics under medium and high loads when the engine is hot.3.Gasoline blended with can affect the engine emission level to some degree.There is an obvious reduction emission of particle,CO and THC when the engine runs with ethanol gasoline,but the NOx emission will increase at some conditions.Under hot conditions,particle emission increases gradually as the volume percent of ethanol increases at low-speed and small-load points.And there is a small decrease of CO and THC with the increase of ethanol when the coolant temperature is 35?.Under hot condition,ethanol gasoline has a significant effect on CO emission reduction at highspeed and large-load,and the larger the ethanol volume fraction,the lower the THC and the higher the NOx emission.