Abstract
Generally, the NO_x (Nitrogen Oxides) density rises and the PM (Particulate matters) emission decreases when the combustion of the diesel engine is promoted. On the other hand, BDF (Bio Diesel Fuel) containing a lot of oxygen promotes the combustion of diesel engines, hence the improvement in thermal efficiency can be expected. However, the previous researches found out that the PM emission of the diesel engine using BDF increased compared with using gas oil. In this research, by using gas oil and BDF, the relationship between the fuel injection pressure and the operating characteristics was examined by testing the performance of the diesel engine with a common rail fuel injection system. As a result, it was clarified that the combustion characteristic of BDF was inferior to gas oil due to high kinematic viscosity, but the NO_x exhaust characteristic and other operating characteristics of the diesel engine could be improved by injecting BDF with high pressure.
