The Influence of Fuel Properties on Particulate Number Emissions from a Direct Injection Spark Ignition Engine
The use of direct injection spark ignition (DISI) engines for passenger cars has increased; providing greater specific performance and lower CO₂ emissions. DISI engines, however, produce more particulate matter (PM) emissions than Port-Fuel-Injected (PFI) engines. Forthcoming European exhaust emissions legislation is addressing concerns over health effects of PM emissions. Accordingly, research into PM emission formation has increased. A model developed by Aikawa et al., (2010) for PFI engines correlated PM number emissions with the vapor pressure and the double bond equivalent (DBE) of the components of the fuel. However there was no independent control of these parameters. This study investigates a particulate emissions index for DISI engines.