Experimental assessment of the potential to decrease diesel NO_X emissions beyond minimum requirements for Euro 6 Real Drive Emissions (RDE) compliance

摘要

Highlights•Study confirms high on-road NOxlevels of a typical diesel Euro 6 car.•New regulations have potential to significantly control on-road NOx.•SCR based emission control achieved conformity factor of 0.53.•Limited side effects of new technology observed for CO2and NH3emissions.Graphical abstractDisplay OmittedAbstractThe objective of this study was to test the potential for NOxemissions improvements on a typical Euro 6 diesel vehicle, following modifications to its emissions control system, under Real Drive Emissions (RDE) testing conditions. A commercially available car was selected and was first measured in its original configuration according to RDE on the road and an initial conformity factor (CF) of 5.4 was determined. Subsequent engine calibration and installation of a Selective Catalytic Reduction (SCR) device were conducted and tested on a fully transient engine dyno setup, which precisely reproduced the engine operation under the on-road RDE test. The NOxreduction achieved with those upgrades was 90%, leading to a CF of 0.53, with no CO2or fuel consumption penalty. These findings demonstrate that diesel vehicles can reach low NOxlevels under real world driving conditions, when well-designed modern exhaust aftertreatment components are installed and properly calibrated.