Effects of Multiple Injections on Diesel Emission and Combustion Characteristics

This study has experimentally clarified the effects the pilot injection fuel quantity and pilot injection timing have on the mode of combustion of the pilot spray and exhaust emissions. The result shows that one of the points to effectively reduce exhaust emissions by pilot injection is to reduce the emissions produced by the pilot combustion itself. For that purpose it is effective to advance the pilot injection timing and to increase of pilot quantity. In this case, dividing the pilot injection into multiple small-quantity shots is a solution to avoid cylinder wall wetting.