System Approach for a Vehicle with Gasoline Direct Injection and Particulate Filter for RDE

Authors

Dr. E. Achleitner, Dipl.-Ing. H. Frenzel, Dipl.-Ing. J. Grimm, Dr. O. Maiwald, Dr. G. Rösel, Dipl.-Ing. P. Senft, Dr. H. Zhang, Continental, Regensburg

Year

2018

Print Info

Fortschritt-Berichte VDI, Series 12, No 807

Summary

Modern vehicles must fulfill very ambitious goals regarding fuel consumption and emissions for the Real Driving Emissions (RDE) legislation with the expanded ambient conditions (for example, ambient temperature and altitude). The transition from the New European Drive Cycle (NEDC) to the dynamic Worldwide Harmonized Light Duty Vehicle Test Procedure (WLTP) and now the RDE requires conformance to emission requirements throughout the entire engine operating map and ambient temperature range. In order to assure conformance to the particulate number (PN) emissions limit, a gasoline particulate filter (GPF) will be installed in most all vehicles in the future. Even with the use of a GPF it is a given development goal to reduce particulate number (PN) raw emissions. The mastery of cold engine operation down to -7°C results in significant additional development requirements. Utilizing 350 bar injector technology and designing the injector calibration around the combustion system with careful calibration of engine control unit (ECU) parameters contributes significantly to the reduction of the PN raw emissions.
Highly transient driving conditions presume a precise and robust control of the combustion process throughout the entire engine operating map. The adherence to stoichiometric engine operation is required to comply with the gaseous emission limits and to reduce PN emissions.
GPF regeneration at low vehicle speeds is a big challenge, especially when the GPF is installed in an underfloor position. A system will be presented that enables GPF regeneration at low vehicle speeds while maintaining low gaseous emissions. This GPF regeneration system also serves as a new type of canister purge system. The system exhibits a fast and robust determination of hydrocarbon (HC) concentration of the purge gas and increased purge rate which is required in hybrid vehicles and internal combustion engines that have been optimized for efficiency.
The communication of vehicles with each other and the traffic infrastructure will in the future render an additional contribution to minimizing fuel consumption and emissions while increasing comfort. Traffic flow and topology of the upcoming route can be considered in the future for GPF regeneration strategies reducing emissions and fuel consumption.
This report presents the interaction among low engine raw emissions, a highly efficient aftertreatment system as well as a newly developed canister purge system.