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A three-dimensional (3-D) computational fluid dynamics (CFD) code has been developed to predict flow dynamics and pressure drop characteristics in geometry-modified filters in which the normalized distance of the outlet channel plugs from the inlet has been varied at 0.25, 0.50, and 0.75. In clean filter simulations, the pressure drop in geometry-modified filters showed higher values than for conventional filters because of the significant change in the pressure field formed inside the channel that determines the amount of flow entering the modified channel. This flow through the modified channel depends on plug position initially but has a maximum limit when pressure difference and geometrical change are compromised. For soot loading simulations, a Lagrangian multiphase flow model was used to interpret the hydrodynamics of particle-laden flow with realistic inputs.

The purpose of this study was to determine the effect of injector nozzle hole size, shape, and finish on performance and emissions in a light-duty diesel engine. Two sets of six-hole valve covered orifice (VCO) nozzles were tested with nearly identical volumetric flow rates but varying geometry and finish. The 17% hydro-erosion (HE) nozzles had a 22% larger discharge coefficient (CD), compared to the 7% HE nozzles. In order to maintain similar volumetric flow rates, the orifice diameter of the 17% HE nozzles were reduced by almost 10%.The nozzles were tested in a 1.7L, four-cylinder, common rail diesel engine, operating on conventional D2 diesel fuel. The 17% HE, conical-shaped nozzles reduced fuel specific particulate matter (PM) and increased fuel specific oxides of nitrogen (NOx) emissions, over the 7% HE, straight-shaped nozzle.

Detailed characteristics of particulate matter (PM) from a gasoline-direct-injection (GDI) engine were analyzed in terms of primary and aggregate particle sizes, morphology, and nanostructures. For the work, PM was collected from exhaust streams of the engine on transmission electron microscope (TEM) grids by using a thermophoretic sampler. To evaluate the effects of engine load and speed on the properties of PM, the engine was operated at loads of 25, 50, and 75% at 1500 and 3000 rpm. In addition, the effects of fuel injection timing on the PM were examined for samples subjected to injection timings of 190, 230, 260, 300 and 330° bTDC at the constant engine load (50% load) and speed (1500 rpm). The results showed that with advancing injection timing, average primary and aggregate particle sizes gradually increased, which implies that fuel-air mixing is a crucial factor influencing particle size.

SunDiesel fuel is a biomass-to-liquid (BTL) fuel that may have certain attributes different from conventional diesel. In this investigation, 100% SunDiesel was tested both in a Mercedes A-Class (MY1999) diesel vehicle and a single-cylinder heavy-duty compression-ignition direct-injection engine. The SunDiesel's emissions and fuel consumption were significantly better than conventional diesel fuel, especially in nitrogen oxides (NOx) reduction. In the vehicle U.S. Environmental Protection Agency (EPA), Federal Test Procedure 75 (FTP-75), and New European Drive Cycle (NEDC) tests, the carbon dioxide emissions on a mile basis (g/mile) from SunDiesel fuel were almost 10% lower than the conventional diesel fuel. Similarly, in the single-cylinder engine steady-state tests, the reductions in brake specific NOx, carbon monoxide (CO), and particulate matter (PM) are equally significant. Combustion analysis, though not conclusive, indicates that there are differences deserving further research.

Detailed soot deposition and oxidation characteristics in a diesel particulate filter (DPF) have been experimentally examined on a unique bench-scale DPF test system that has a visualization window. The filtration and regeneration processes were visualized to examine soot deposition and oxidation behaviors on the filter channel surfaces, along with measurements of pressure drop across the filter. The pressure drop caused by trapped soot was separated from the measured total pressure drop by subtracting the pressure drop caused by the clean filter itself. Then, the soot-derived pressure-drop data, normalized (non-dimensionalized) by the volumetric flow rate, exhaust gas viscosity, and DPF volume, were used to compare filtration and regeneration characteristics at different experimental conditions, independently of flow conditions.

The objective of this paper is to present the results of diesel exhaust aftertreatment testing and analysis done under the FreedomCAR program. Nitrogen Oxides (NOx) adsorber technology was selected based on a previous investigation of various NOx aftertreatment technologies including non-thermal plasma, NOx adsorber and active lean NOx. Particulate Matter (PM) emissions were addressed by developing a catalyzed particulate filter. After various iterations of the catalyst formulation, the aftertreatment components were integrated and optimized for a light duty vehicle application. This compact exhaust aftertreatment system is dual leg and consists of a sulfur trap, NOx adsorbers, and catalyzed particulate filters (CPF). During regeneration, supplementary ARCO ECD low-sulfur diesel fuel is injected upstream of the adsorber and CPF in the exhaust. Steady state and transient emission test results with and without the exhaust aftertreatment system (EAS) are presented.

EcoCAR 2: Plugging In to the Future (EcoCAR) is North America's premier collegiate automotive engineering competition, challenging students with systems-level advanced powertrain design and integration. The three-year Advanced Vehicle Technology Competition (AVTC) series is organized by Argonne National Laboratory, headline sponsored by the U. S. Department of Energy (DOE) and General Motors (GM), and sponsored by more than 28 industry and government leaders. Fifteen university teams from across North America are challenged to reduce the environmental impact of a 2013 Chevrolet Malibu by redesigning the vehicle powertrain without compromising performance, safety, or consumer acceptability. During the three-year program, EcoCAR teams follow a real-world Vehicle Development Process (VDP) modeled after GM's own VDP. The VDP serves as a roadmap for the engineering process of designing, building and refining advanced technology vehicles.

At 70 miles per hour, overcoming aerodynamic drag represents about 65% of the total energy expenditure for a typical heavy truck vehicle. The goal of this US Department of Energy supported consortium is to establish a clear understanding of the drag producing flow phenomena. This is being accomplished through joint experiments and computations, leading to the intelligent design of drag reducing devices. This paper will describe our objective and approach, provide an overview of our efforts and accomplishments related to drag reduction devices, and offer a brief discussion of our future direction.

SunDiesel™ is an alternative bio-fuel derived from wood chips that has certain properties that are superior to those of conventional diesel (D2). In this investigation, 100% SunDiesel was tested in a Mercedes A-Class (model year 1999), 1.7L, turbocharged, direct-injection diesel engine (EURO II) equipped with a common-rail injection system. By using an endoscope system, Argonne researchers collected in-cylinder visualization data to compare the engine combustion characteristics of the SunDiesel with those of D2. Measurements were made at one engine speed and load condition (2,500 rpm, 50% load) and four start-of-injection (SOI) points, because of a limited source of SunDiesel fuel. Significant differences in soot concentration, as measured by two-color optical pyrometry, were observed. The optical and cylinder pressure data clearly show significant differences in combustion duration and ignition delay between the two fuels.

The particulate matter (PM) produced from a diesel engine-simulating combustor was characterized in its morphology, microstructure, and fractal geometry by using a unique thermophoretic sampling and Transmission Electron Microscopy (TEM) system. These results revealed that diesel PM produced from the laboratory-scale burner showed similar morphological characteristics to the particulates produced from diesel engines. The flame air/fuel ratio and the particulate temperature history have significant influences on both particle size and fractal geometry. The primary particle sizes were measured to be 14.7 nm and 14.8 nm under stoichiometric and fuel-rich flame conditions, respectively. These primary particle sizes are smaller than those produced from diesel engines. The radii of gyration for the aggregate particles were 83.8 nm and 47.5 nm under these two flame conditions.

Exhaust gas recirculation (EGR) is a commonly used technique for the reduction of Nitrogen oxide (NOx) emissions from internal combustion engines. However, it is generally known that the use of EGR will cause an increase in emissions of particulate matter (PM). The effects of EGR operating mode on particulate morphology were investigated for a 1.7-liter light-duty diesel engine. This engine was equipped with a turbocharged and inter-cooled air induction system, a common-rail direct fuel injection system, and an EGR system. A rapid prototyping electronic control system (RPECS) was developed to operate this engine at various EGR rates under different conditions (i.e. constant boost pressure, constant oxygen-to-fuel ratio (OFR)). A unique thermophoretic sampling system was employed to collect particulates directly from exhaust manifold after exhaust valves.

The detailed morphological properties of diesel particulate matter were analyzed along the exhaust system at various engine operating conditions (in a range of 1000 - 2500 rpm and 10 - 75 % loads of maximum torques). A 1.7-L turbocharged light-duty diesel engine was powered with California low-sulfur diesel fuel injected by a common-rail injection system, of which particulate emissions were controlled by an exhaust gas recirculation (EGR) system and two oxidation catalysts. A unique thermophoretic sampling system first developed for internal combustion engine research, a high-resolution transmission electron microscope (TEM), and a customized image processing/data acquisition system were key instruments that were used for the collection of particulate matter, subsequent imaging of particle morphology, and detailed analysis of particle dimensions and fractal geometry, respectively.

The Center for Transportation Research (CTR) Vehicle Systems team modified a Nissan CK-2 Continuously Variable Transmission (CVT) for a diesel hybrid powertrain application. Mechanical and electrical modifications were made to the CVT, both internal and external to the transmission. The goal of this experiment was to investigate and demonstrate the potential of CVT for diesel engines hybrid electric vehicles (HEVs) in fuel economy and emissions. The test set-up consisted of a diesel engine coupled to an electric motor driving a Continuously Variable Transmission (CVT). This hybrid drive is connected to a dynamometer and a DC electrical power source creating a vehicle context by combining advanced computer models and emulation techniques. The experiment focuses on the impact particular transmission control strategies have on measured fuel economy and emissions specifically, nitrogen oxides (NOx) and particulate matter (PM).

Alternative fuels for internal combustion engines have been the subject of numerous studies. The new U.S. Renewable Fuel Standard has made it a requirement to increase the production of ethanol and advanced biofuels to 36 billion gallons by 2022. Because corn-based ethanol will be capped at 15 billion gallons, 21 billion gallons must come from the advanced biofuels category. A potential source to fill the gap may be butanol and its isomers as they possess fuel properties superior to ethanol. Recently, concerns have been raised about emission of currently non-regulated constituents, aldehydes in particular, from alcohol-based fuels. In an effort to assess the relative impact of the U.S. Renewable Fuel Standards on emissions from a modern gasoline engine, both regulated and non-regulated gas constituents were measured from the combustion of three different alcohol isomers in a modern direct-injected (DI) spark ignition (SI) gasoline engine.

Over the past couple of years, Argonne National Laboratory has tested, analyzed, and validated automobile models for the light duty vehicle class, including several types of powertrains including conventional, hybrid electric, plug-in hybrid electric and battery electric vehicles. Argonne’s previous works focused on the light duty vehicle models, but no work has been done on medium and heavy-duty vehicles. This study focuses on the validation of shifting control in advanced automatic transmission technologies for medium duty vehicles by using Argonne’s model-based high-fidelity, forward-looking, vehicle simulation tool, Autonomie. Different medium duty vehicles, from Argonne’s own fleet, including the Ram 2500, Ford F-250 and Ford F-350, were tested with the equipment for OBD (on-board diagnostics) signal data record. For the medium duty vehicles, a workflow process was used to import test data.

Particulate and gaseous emissions from a Mitsubishi Legnum GDI™ wagon were measured for FTP-75, HWFET, SC03, and US06 cycles. The vehicle has a 1.8-L spark-ignition direct-injection engine. Such an engine is considered a potential alternative to the compression-ignition direct-injection engine for the PNGV program. Both engine-out and tailpipe emissions were measured. The fuels used were Phase-2 reformulated gasoline and Indolene. In addition to the emissions, exhaust oxygen content and exhaust-gas temperature at the converter inlet were measured. Results show that the particulate emissions are measurable and are significantly affected by the type of fuel used and the presence of an oxidation catalyst. Whether the vehicle can meet the PNGV goal of 0.01 g/mi for particulates depends on the type of fuel used. Both NMHC and NOx emissions exceed the PNGV goals of 0.125 g/mi and 0.2 g/mi, respectively. Meeting the NOx goal will be especially challenging.

A 1998 Toyota Corona passenger car with a direct injection spark ignition (DISI) engine was tested via a variety of driving cycles using California Phase 2 reformulated gasoline. A comparable PFI vehicle was also evaluated. The standard driving cycles examined were the Federal Test Procedure (FTP), Highway Fuel Economy Test, US06, simulated SC03, Japanese 10-15, New York City Cycle, and European ECE+EDU. Engine-out and tailpipe emissions of gas phase species were measured each second. Hydrocarbon speciations were performed for each phase of the FTP for both the engine-out and tailpipe emissions. Tailpipe particulate mass emissions were also measured. The results are analyzed to identify the emissions challenges facing the DISI engine and the factors that contribute to the particulates, NOx, and hydrocarbon emissions problems of the DISI engine.

While sulfur in diesel fuels helps reduce friction and prevents wear and galling in fuel pump and injector systems, it also creates environmental pollution in the form of hazardous particulates and SO2 emissions. The environmental concern is the driving force behind industry's efforts to come up with new alternative approaches to this problem. One such approach is to replace sulfur in diesel fuels with other chemicals that would maintain the antifriction and antiwear properties provided by sulfur in diesel fuels while at the same time reducing particulate emissions. A second alternative might be to surface-treat fuel injection parts (i.e., nitriding, carburizing, or coating the surfaces) to reduce or eliminate failures associated with the use of low-sulfur diesel fuels. Our research explores the potential usefulness of a near-frictionless carbon (NFC) film developed at Argonne National Laboratory in alleviating the aforementioned problems.

Indoor laboratory tire testing on flat belt machines and tire testing on the actual road yield different results. Testing on the machine offers the advantage of repeatability of test conditions, control of the environmental condition, and performance evaluation at extreme conditions. However, certain aspects of the road cannot be reproduced in the laboratory. It is thus essential to understand the connection between the machine and the road, as tires spend all their life on the road. This research, investigates the reasons for differences in tire performance on the test machine and the road. The first part of the paper presents a review on the differences between tire testing in the lab and on the road, and existing methods to account for differences in test surfaces.

Numerical simulations of soot formation were performed for n-dodecane spray using the transported probability density function (TPDF) method. Liquid n-dodecane was injected with 1500 bar fuel pressure into a constant-volume vessel with an ambient temperature, oxygen volume fraction and density of 900 K, 15% and 22.8 kg/m3, respectively. The interaction by exchange with the mean (IEM) model was employed to close the micro-mixing term. The unsteady Reynolds-averaged Navier-Stokes (RANS) equations coupled with the realizable k-ε turbulence model were used to provide turbulence information to the TPDF solver. A 53-species reduced n-dodecane chemical mechanism was employed to evaluate the reaction rates. Soot formation was modelled with an acetylene-based two-equation model which accounts for simultaneous soot particle inception, surface growth, coagulation and oxidation by O2 and OH.