For better understanding of diesel emissions in real world, the effects of driving conditions and fuel properties on diesel emissions were studied.
A diesel engine system that is compliant to the Japanese New Short Term Regulation (J-2003 regulation) was used in this study. Major technologies for emission reduction were a common-rail high-pressure fuel injection equipment system, a cooled exhaust gas recirculation (EGR) system and a diesel oxidation catalyst (DOC).
Various driving modes with a wide range of average vehicle speeds and accelerations were selected, including US FTP, US Highway, Japanese JC08, Japanese JE05, Tokyo Metropolitan Government #2, #5 and #8.
Several kinds of test fuels of which characteristics were drastically changed in distillation range, aromatics content and sulfur content were used. A test fuel that complies with the Category-4 Specification of the World-Wide Fuel Charter (WWFC) was included.
Emissions of PM (SOF and soot), NOx, THC, CO, CO2 and fuels economies were examined. Cleanup effect of the DOC was also investigated.