AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Physicochemical Assessment of Exhaust Emissions from a Light-duty Gasoline Direct Injection Engine Operated with Conventional and Ethanol-blended Fuels
NAOMI ZIMMERMAN, Manuel Ramos, Cheol-Heon Jeong, Krystal J. Godri-Pollitt, James S. Wallace, Greg J. Evans, SOCAAR, University of Toronto
Abstract Number: 99 Working Group: Combustion
Abstract Gasoline vehicles are increasingly being equipped with direct injection (GDI) engines in lieu of traditional port fuel injection engines to meet regulatory limits on fuel economy and carbon dioxide emissions in North America and Europe, respectively. Analogous to diesel engines, GDI engines emit large quantities of particles; however, unlike diesel, there are currently no regulatory limits on GDI particulate matter (PM) emissions. Accordingly, future legislation of PM emissions from GDI vehicles requires a comprehensive understanding of GDI exhaust emissions, including the impact of ethanol-blended fuels, which are expected to reduce PM exhaust concentrations.
In this ongoing study, a light-duty GDI engine (2012 Ford Focus) was operated with an engine dynamometer under five driving conditions: cold start, hot start, simulated urban driving, simulated highway cruise, and a simulated passing maneuver. Emissions were generated using ethanol-gasoline blends of commercially available gasoline and anhydrous ethyl alcohol ranging from E0 (0% ethanol) to E85 (85% ethanol).
Exhaust emissions were characterized along three sampling lines: 1) real-time measurement of gaseous regulated (NOx, THC, CO) and unregulated pollutants with an MKS MultiGas 2030-HS FTIR; 2) collection of PM on filters for gravimetric analysis and offline measurement of metal species and elemental and organic carbon concentrations; and 3) dilution in a rotary disk diluter (TSI 379020A) for real-time measurement of particle number concentration and size distribution (TSI 3090), and black carbon concentration (DMT PASS-3). Exhaust concentrations were normalized to fuel-based emission factors for a direct comparison to on-road emission factors measured from GDI-equipped vehicles. This study aims to help forecast the impact of increasing GDI and biofuel integration on traffic-related air pollution levels.