Refine Your Search

Search Results

Viewing 1 to 2 of 2
Technical Paper

Cold-Running NOx Emissions Comparison between Conventional and Hybrid Powertrain Configurations Using Real World Driving Data

2016-04-05
2016-01-1010
Internal combustion engine (ICE) cold-start is an issue that occurs either in conventional and hybrid powertrains before the ICE reaches its normal operation temperature, affecting both fuel consumption due to higher heat losses, and pollutant emissions due to low catalytic converter temperatures. The study of cold start emissions on conventional powertrains has been extensively addressed, although typically under laboratorial conditions, however studies addressing the impact of this phenomenon on hybrid powertrains is still reduced. Hybrid electric (HEV) and plug-in hybrid electric (PHEV) vehicles usually incorporate technologies to manage the battery and ICE power supply leading to ICE on/off operation under regular driving, which can result in a decrease on catalytic converter efficiency (due to cooling).
Technical Paper

Comparison of Data Analysis Methods for European Real Driving Emissions Regulation

2017-03-28
2017-01-0997
The gap between regulated emissions from vehicle certification procedures and real-world driving has become increasingly wider, particularly for nitrogen oxides (NOx). Even though stricter emission regulations have been implemented, NOx emissions are dependent on specific, short-duration driving events which are difficult to control, therefore high concentrations of these pollutants are still being measured in European cities. Under certification procedures, vehicle emissions compliance is evaluated through standards, recurring to driving cycles performed on chassis dynamometer under controlled laboratory conditions. Different countries use different standard cycles, with the US basing their certification cycle on FTP-75 and Europe using NEDC (Euro 5/6c)/WLTP (Euro 6d).
X