Study On The Combustion And Emission Characteristics Of Gasoline Direction Injection Engine Fueled With Hydrous Ethanol Gasoline Blended Fuel

With the scarcity of fossil fuels and the stringency of emission regulations, humans have to find renewable energy sources to replace fossil energy sources. Ethanol is a common alternative fuels which has a wide variety of sources. Ethanol has high octane and good antiknock, and the compression ratio can be improved to increase the thermal efficiency of gasoline engines. Thus, ethanol is suitable for widespread use in gasoline engines. In this paper, hydrous ethanol instead of gasoline was used, which greatly reduces the production cost especially in dehydration process. Gasoline Direct Injection has good cold starting performance, low fuel consumption, and fast response, which enables lean-burn combustion and other combustion mode. Aiming at emission characteristics related infrastructure issue of GDI gasoline engine fueling with hydrous ethanol gasoline emission characteristics related infrastructure issues, conducted a study of combustion and emission characteristics of gasoline, E10W and E20W blended fuel was studied. To examine the influence of engine control parameters for GDI gasoline engine fueled with gasoline influence of hydrous ethanol, the excess air ratio, ignition timing and fuel injection timing was adjusted. Meanwhile, ethanol gasoline chemical kinetics model was constricted to explore the hydrous ethanol gasoline fuel emissions characteristics, which has provided a theoretical basis for reducing its emissions.The result of combustion and emission characteristics of GDI gasoline engine in different load conditions for low and medium speed showed that heat release rate the pressure rise rate and peak pressure cylinder, equivalence specific fuel consumption, CO emissions, the amount of particulate matter emissions and concentrations of THC emissions with hydrous ethanol gasoline are lower than gasoline.NOx emissions vary with the mean effective pressure is large, at0.2?0.6MPa, the hydrous ethanol fueled with gasoline increased NOx emissions, while at the0.6?1.1MPa, it reduce NOx emissions.The result of emission characteristics of different adjusted control parameters showed that when excess air ratio decreased, the maximum explosion pressure cylinder, the peak heat release rate and maximum cylinder combustion temperature, and combustion rate increased CO, THC, and the total amount of state gathered exhaust particles and particulate matter emissions increased, NOx emissions increased and then decreased. When ignition advance angle increased, the peak cylinder pressure and pressure rise rate decreases, the peak corresponding to the crank angle after the shift, CO, THC, NOx and the total amount of particulate emissions gradually increased. When injection timing advanced, the heat release rate, cylinder pressure and rate of pressure rise peak increased. For each fuel, there are optimum injection timings to reduce the CO, THC, NOx and particulate matter emissions, which was influenced by the amount of the lowest point of the mean effective pressure.Based on the sensitivity analysis method, n-heptane, iso-octane and ethanol as a high temperature and low temperature sensitivity analysis, toluene and toluene precursor substances do sensitivity analysis and by the reaction path analysis, the higher the sensitivity coefficients and the main production and consumption of substances play an important role in the physical and chemical reaction equation reservations construct a reduced chemical kinetics model including134kinds of substances and315kinds of reactions. The results showed that ignition delay of reduced mechanism has good predictive ability.