Study On Combustion And Emission Characteristics Of Diesel Engine Fueled With Microemulsified Biodiesel

The biodiesel is close in the physics and chemistry characteristic with the diesel, non-toxic and can be degraded and also is one kind of green renewable energy. At present it has already served as alternate fuel for crude oil automobile's in many countries. However, because biodiesel contains 10% oxygen, it may cause the automobile NOx emissions increasing. To face more and stricter emissions laws and regulations, the people carry on many attempts and the research to reduce the biodiesel NOx emissions. Based on the biodiesel as well as in the micro emulsified technology full understanding, this article conducts the research to the biodiesel micro-emulsification. On the base of obtaining different recipe micro emulsified biodiesel to determine final two kinds of micro emulsified biodiesel, and carried on the power, fuel efficiency, the combustion and the emissions characteristic comparative experiment on the engine.The research result indicated: the maximum quality of water dissolving to the micro emulsified biodiesel and the stability were affected by the surface active agent types and the quality. The maximum quality of water dissolving and the stability of same formula's micro emulsified biodiesel were not affected by the emulsified method. Compared with the pure biodiesel, when the engine burns with the micro emulsified biodiesel, the external characteristic power and the torque reduce slightly, specific fuel consumption increases, specific energy consumption reduces; When the engine burns with the micro emulsified biodiesel, smoke and the NOx emissions reduce effectively, HC and the CO emissions increase slightly, but the absolute value is small. Compared with the pure biodiesel, when the engine bums with the micro emulsified biodiesel, the curve of cylinder pressure, pressure rise rate, heat release rate as well as cumulative fuel burned appear obviously back moving trend. The ignition delay period lengthens, and the combustion lags, but the combustion duration is short, the combustion and the heat release centralize, the peak pressure elevation rate and the peak instantaneous combustion heat release rate increase.In the situation that power reduces not too much, the engine fueled with the micro emulsified biodiesel can reduce the emissions effectively and the effective energy consumption rate, under two big subjects of energy saving and environmental protection , studying and developing the micro emulsified biodiesel has become one of the automobile new energy research subjects .