Effects of fuel cetane number and aromatics on combustion process and emissions of a direct-injection diesel engine

Abstract

This study investigated the effects of fuel properties on combustion characteristics and emissions such as NO x . THC, smoke and particulate in a direct-injection diesel engine. Cetane number and aromatic content of fuels were varied independently. The results showed that reducing cetane number resulted in the increase of NO x and the decrease of particulate at high load. The aromatic content had little effect on combustion characteristics. However, increasing aromatic content for high cetane number fuel resulted in high NO x and particulate emissions. For low cetane number fuel, increasing aromatic content produced high THC emission at retarded injection timing. In the case of high injection pressure, fuel properties showed little effect on particulate emissions.