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Gaseous compounds, particle number and size distribution measurements on a gasoline direct injection (GDI) vehicle and a port fuel injection (PFI) vehicle were conducted over the U.S. Federal Test Procedure 75 (FTP-75) and US06 Supplemental Federal Test Procedure (US06) on Tier 2 certification gasoline (E0) and a 10% by volume ethanol (E10). Overall the GDI test vehicle was observed to have lower fuel consumption than the PFI test vehicle by 6% and 3% for the FTP-75 and US06 drive cycles, respectively. When using E10, this GDI vehicle had a better fuel consumption than the PFI vehicle by 7% and 5% for the FTP-75 and US06 drive cycles, respectively. For particle emissions, the solid particle number emission rates for the GDI, equipped with a 3-way catalyst in its original equipment manufacturer configuration (i.e., stock GDI), were 10 and 31 times higher than the PFI vehicle for the FTP-75 and US06 drive cycles, respectively.

Gaseous and particle emissions from a gasoline direct injection (GDI) and a port fuel injection (PFI) vehicle were measured at various ambient temperatures (22°C, -7°C, -18°C). These vehicles were driven over the U.S. Federal Test Procedure 75 (FTP-75) and US06 Supplemental Federal Test Procedure (US06) on Tier 2 certification gasoline (E0) and 10% by volume ethanol (E10). Emissions were analyzed to determine the impact of ambient temperature on exhaust emissions over different driving conditions. Measurements on the GDI vehicle with a gasoline particulate filter (GPF) installed were also made to evaluate the GPF particle filtration efficiency at cold ambient temperatures. The GDI vehicle was found to have better fuel economy than the PFI vehicle at all test conditions. Reduction in ambient temperature increased the fuel consumption for both vehicles, with a much larger impact on the cold-start FTP-75 drive cycle observed than for the hot-start US06 drive cycle.

Two large, heavy light-duty gasoline vehicles (2004 model year Ford F-150 with a 5.4 liter V8 and GMC Yukon Denali with a 6.0 liter V8) were baselined for emission performance over the FTP driving cycle in their stock configurations. Advanced emission systems were designed for both vehicles employing advanced three-way catalysts, high cell density ceramic substrates, and advanced exhaust system components. These advanced emission systems were integrated on the test vehicles and characterized for low mileage emission performance on the FTP cycle using the vehicle's stock engine calibration and, in the case of the Denali, after modifying the vehicle's stock engine calibration for improved cold-start and hot-start emission performance.

Original equipment (OE) catalytic converters are designed to last the life of properly tuned and maintained vehicles. Many high mileage vehicles require a replacement converter because the original catalyst was damaged, destroyed, or removed, and the cost of a new OE converter on an older vehicle is difficult to justify. In the U.S., a federal aftermarket converter program has been in place since 1986 (California in 1988) and it has resulted in the replacement of over 50 million converters. Both Federal and California programs have required aftermarket converters to meet minimum performance and durability standards. Increasingly tighter emission standards and durability requirements for new light-duty vehicles have resulted in significant technology improvements in three-way automotive catalysts, however these advancements have not always made their way into aftermarket converters.

The U.S. Tier 2 emission regulations require sophisticated exhaust aftertreatment technologies for diesel engines. One of the projects under the U.S. Department of Energy's (DOE's) Advanced Petroleum Based Fuels - Diesel Emission Controls (APBF-DEC) activity focused on the development of a light-duty passenger car with an integrated NOx (oxides of nitrogen) adsorber catalyst (NAC) and diesel particle filter (DPF) technology. Vehicle emissions tests on this platform showed the great potential of the system, achieving the Tier 2 Bin 5 emission standards with new, but degreened emission control systems. The platform development and control strategies for this project were presented in 2004-01-0581 [1]. The main disadvantage of the NOx adsorber technology is its susceptibility to sulfur poisoning. The fuel- and lubrication oil-borne sulfur is converted into sulfur dioxide (SO2) in the combustion process and is adsorbed by the active sites of the NAC.

In this study, a 15-L heavy-duty diesel engine and an emission control system consisting of diesel oxidation catalysts, NOx adsorber catalysts, and diesel particle filters were evaluated over the course of a 2000 hour aging study. The work is a follow-on to a previously documented development effort to establish system regeneration and sulfur management strategies. The study is one of five projects being conducted as part of the U.S. Department of Energy's Advanced Petroleum Based Fuels - Diesel Emission Control (APBF-DEC) activity. The primary objective of the study was to determine if the significant NOx and PM reduction efficiency (>90%) demonstrated in the development work could be maintained over time with a 15-ppm sulfur diesel fuel. The study showed that high NOx reduction efficiency can be restored after 2000 hours of operation and 23 desulfation cycles.

The 51 SAE technical papers included in this volume touch on all aspects of the significant systems engineering effort that has occurred within the broad automobile catalytic emission control technology base during the past fifteen years. Dr. Joseph Kubsh, Deputy Director of the Manufacturers of Emission Controls Association, hand-selected the publications for this volume from hundreds of technical papers published by SAE that address catalytic emission control technologies for light-duty gasoline vehicles. These papers include efforts to improve the performance, durability, and cost effectiveness of the catalytic converter systems used on gasoline stoichiometric engines and the integration of these three-way catalysts into sophisticated powertrains capable of operating at near-zero tailpipe emission levels.