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Biodiesel (i.e., mono-alkyl esters of long chain fatty acids derived from vegetable oils and animal fats) is a renewable diesel fuel providing life-cycle greenhouse gas emission reductions relative to petroleum-derived diesel. With the expectation that there would be widespread use of biodiesel as a substitute for ultra-low sulfur diesel (ULSD), there have been many studies looking into the effects of biodiesel on engine and aftertreatment, particularly its compatibility to the current aftertreatment technologies. The objective of this study was to generate experimental data to measure the effectiveness of a current technology diesel oxidation catalysts (DOC) to oxidize soy-based biodiesel at various blend levels with ULSD. Biodiesel blends from 0 to 100% were evaluated on an engine using a conventional DOC.

The project objective was to generate experimental data to evaluate the impact of metals doped B20 on DPF ash loading and performance compared to that of conventional petrodiesel. Accelerated ash loading was conducted on two DPFs – one exposed to regular diesel fuel and the other to B20 containing metal dopants equivalent to 4 ppm B100 total metals (currently total metals are limited to 10 ppm in ASTM D6751, the standard for B100). Periodic performance evaluations were conducted on the DPFs at 10 g/L ash loading intervals. After the evaluations at 30 g/L, the DPF was cleaned with a commercial DPF cleaning machine and another round of DPF evaluations were conducted. A comparison of the effect of ash loading with the two fuels and DPF cleaning is presented. The metals doped B20 fuel resulted in ash that was similar to that deposited when exposed to ULSD (lube oil ash) and exhibited similar ash cleaning removal efficiency.

This project’s objective was to generate experimental data to evaluate the impact of metals doped B20 on diesel particle filter (DPF) ash loading and performance compared to that of conventional petrodiesel. The effect of metals doped B20 vs. conventional diesel on a DPF was quantified in a laboratory controlled accelerated ash loading study. The ash loading was conducted on two DPFs – one using ULSD fuel and the other on B20 containing metals dopants equivalent to 4 ppm B100 total metals. Engine oil consumption and B20 metals levels were accelerated by a factor of 5, with DPFs loaded to 30 g/L of ash. Details of the ash loading experiment and on-engine DPF performance evaluations are presented in the companion paper (Part I). The DPFs were cleaned, and ash samples were taken from the cleaned material. X-ray Fluorescence (XRF), X-Ray Photoelectron Spectroscopy (XPS) and X-Ray Diffraction (XRD) were conducted on the ash samples.

Particulate matter (PM) and NOX are two major pollutants generated by diesel engines. Modern diesel aftertreatment systems include selective catalytic reduction (SCR) technology that helps reduce tailpipe NOX emissions when coupled with diesel exhaust fluid (DEF/urea) injection. However, this process also results in the formation of urea derived byproducts that can influence non-volatile particle number (PN) measurement conducted in accordance with the European Union (EU) Particle Measurement Program (PMP) protocol. In this program, an experimental investigation of the impact of DEF injection on tailpipe PN and its implications for PMP compliant measurements was conducted using a 2015 model year 6.7 L diesel engine equipped with a diesel oxidation catalyst, diesel particulate filter and SCR system. Open access to the engine controller was available to manually override select parameters.

Recent legislation enacted for the European Union (EU) and the United States calls for a substantial reduction in particulate mass (and number in the EU) emissions from gasoline spark-ignited vehicles. The most prominent technology being evaluated to reduce particulate emissions from a gasoline vehicle is a wall flow filter known as a gasoline particulate filter (GPF). Similar in nature to a diesel particulate filter (DPF), the GPF will trap and store particulate emissions from the engine, and oxidize said particulate with frequent regeneration events. The GPF will also collect ash particles in the wall flow substrate, which are metallic components that cannot be oxidized into gaseous components. Due to high temperature operation and frequent regeneration of the GPF, the impact of ash on the GPF has the potential to be substantially different from the impact of ash on the DPF.

Gasoline direct injected (GDI) engines are becoming a concern with respect to particulate matter (PM) emissions. The upcoming 2014 Euro 6 regulations may require a drastic reduction in solid particle number emissions from GDI engines and the proposed California Air Resources Board (CARB) LEV III regulations for 2014 and 2017 will also require some PM reduction measures. As a result, it is necessary to characterize PM emissions from GDI engines and investigate strategies that suppress particle formation during combustion. The main focus of this work was on using exhaust gas recirculation (EGR) as a means to reduce engine-out particle emissions from a GDI engine with an overall stoichiometric fuel to air mixture. A small displacement, turbocharged GDI engine was operated at a variety of steady-state conditions with differing levels of EGR to characterize total (solid plus volatile) and solid particle emissions with respect to size, number, and soot or black carbon mass.

A novel urea evaporation and mixing device has been developed to improve the overall performance of a urea-SCR system. The device was tested with a MY2007 Cummins ISB 6.7L diesel engine equipped with an SCR aftertreatment system. Test results show that the device effectively improved the overall NO conversion efficiency of the SCR catalyst over both steady-state and transient engine operating conditions, while NH₃ slip from the catalyst decreased.

Particulate Matter (PM) emissions from gasoline direct injection (GDI) engines are becoming a concern and will be limited by future emissions regulations, such as the upcoming Euro 6 legislation. Therefore, PM control from a GDI engine will be required in addition to effective reduction of HC, CO and NOx emissions. Three different integrated aftertreatment systems were developed to simultaneously reduce PM, HC, CO and NOx emissions from a preproduction Ford 3.5L EcoBoost GTDI engine, with PM reduction as the major focus. PM reduction efficiencies were calculated based on the measurements of PM mass and solid particle number. Test results show that tradeoffs exist in the design of aftertreatment systems to significantly reduce PM emissions from a GDI engine.

Increasing fuel costs and the desire for reduced dependence on foreign oil have brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. One of the obstacles to the increased use of diesel engines in this platform is the Tier 2 emission standards. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies-such as common rail fuel injection systems, low-sulfur diesel fuel, oxides of nitrogen (NOX) adsorber catalysts or NACs, and diesel particle filters (DPFs)-allows for the development of powertrain systems that have the potential to comply with these future requirements. In support of this, the U.S. Department of Energy (DOE) has engaged in several test projects under the Advanced Petroleum Based Fuels-Diesel Emission Control (APBF-DEC) activity [1, 2, 3, 4, 5].

Increasing fuel costs and the desire for reduced dependence on foreign oil has brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. The main obstacle to the increased use of diesel engines in this platform is the upcoming extremely stringent, Tier 2 emission standard. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies such as common rail fuel injection systems, low sulfur diesel fuel, NOX adsorber catalysts (NAC), and diesel particle filters (DPFs) allow the development of powertrain systems that have the potential to comply with these future requirements. In meeting the Tier 2 emissions standards, the heavy light-duty trucks (HLDTs) and medium-duty passenger vehicles (MDPVs) will face the greatest technological challenges. In support of this, the U.S.

Increasing fuel costs and the desire for reduced dependence on foreign oil has brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. The main obstacle to the increased use of diesel engines in this platform is the upcoming extremely stringent, Tier 2 emission standard. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies such as common rail fuel injection systems, low sulfur diesel fuel, NOX adsorber catalysts (NAC), and diesel particle filters (DPFs) allow the development of powertrain systems that have the potential to comply with these future requirements. In meeting the Tier 2 emissions standards, the heavy light-duty trucks (HLDTs) and medium-duty passenger vehicles (MDPVs) will face the greatest technological challenges. In support of this, the U.S.

This paper describes the results of a study that examined the mechanism of phased perturbation as an emissions control technique. Phased perturbation involves independently controlling the fuel delivered to each bank of a dual bank engine (or each cylinder of a single manifold engine), which allows the two banks to have an adjustable, relative Air/Fuel (A/F) perturbation phase-shift from one another. The phase shifted exhaust is then recombined to achieve a near stoichiometric mixture prior to entering a single underbody catalyst. Phase shifting the exhaust Air/Fuel ratio creates a situation in which both rich exhaust constituents (unburnt hydrocarbons and carbon monoxide) and lean exhaust constituents (oxygen and oxides of nitrogen) arrive at the catalyst at the same time. The results of the study showed that phased perturbation produced a significant effect on A/F control and catalyst THC, CO, and NOx efficiency.

A program to demonstrate the performance of advanced emission control systems in light of the California LEV II light-duty vehicle standards and the EPA's consideration of Tier II emission standards was conducted. Two passenger cars and one light-duty pick-up truck were selected for testing, modification, and emission system performance tuning. All vehicles were 1997 Federal Tier I compliant. The advanced emission control technologies evaluated in this program included advanced three-way catalysts, high cell density substrates, and advanced thermally insulated exhaust components. Using these engine-aged advanced emission control technologies and modified stock engine control strategies (control modifications were made using an ERIC computer intercept/control system), each of the three test vehicles demonstrated FTP emission levels below the proposed California LEV II 193,000 km (120,000 mile) ULEV levels.

The emission and flow restriction characteristics of three different ceramic substrates with varying wall thickness and cell density (400 cpsi/6.5 mil, 600/4.3, and 600/3.5) are compared. These 106mm diameter substrates were catalyzed with similar amounts of washcoat and fabricated into catalytic converters having a total volume of 2.0 liters. A Pd/Rh catalyst technology was applied at a concentration of 6.65 g/l and a ratio of 20/1. Three sets of converters (two of each type) were aged for 100 hours on an engine dynamometer stand. After aging, the FTP performance of these converters were evaluated on an auto-driver FTP stand using a 2.4L, four-cylinder prototype engine and on a 2.4L, four-cylinder prototype vehicle. A third set of unaged converters was used for cold flow restriction measurements and vehicle acceleration tests.