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Historically, fuel cost conscious customers have tended to purchase diesel passenger cars. However, with increasing competition from alternative fuels and lean burn and direct injection gasoline fuelled engines, diesel engined vehicles currently face tough challenges from the point of fuel economy and emissions. In gasoline engines, low viscosity friction modified oils have demonstrated their potential for reducing internal engine friction and thus improving fuel economy, without adversely effecting engine durability. These fuel economy improvements have led to the introduction of such a low viscosity friction modified 5W-30 oil as the initial and service fill for the majority of Ford products sold in Europe. The trend towards even lower viscosities continues. To assess the potential benefits and issues of moving to 5W-20 in diesel engines, a short pilot study has been conducted using a Ford 1.8l direct injection diesel engine.

The effect of sampling conditions on the diesel exhaust aerosol characteristics has been studied so far with the application of Electrostatic Classifiers under steady state conditions. This paper aims at examining the same effects with application of an Electrical Low Pressure Impactor under transient engine operating conditions. Explanation of the results obtained takes into account the different operational characteristics of this new technique (recorded magnitude, size range and resolution). The study confirms particle formation in the dilution tunnel and downstream of a DPF and also coagulation of liquid particles in the tunnel. However, separation of the liquid particle phase has led to modification of the aerosol properties in a direction which may be conversely recorded by instruments based on different operation principles.

Measurements of exhaust emissions were conducted for six alternative diesel fuels in a 2.2L, direct-injection diesel engine. Triplicate 13-mode, steady-state test sequences were performed for each fuel, as well as an ASTM D975 low sulfur No. 2 diesel (2DLS) control fuel, which served as the baseline. The alternative fuels include California Reference fuel, a low-sulfur diesel, a Fischer-Tropsch diesel, and three blends: 20 percent Fischer-Tropsch/80 percent low-sulfur diesel; 20 percent biodiesel/80 percent low-sulfur diesel; and 15 percent DMM/85 percent low-sulfur diesel. All six alternative fuel formulations demonstrated benefits by reducing particulate matter (PM) emissions without significant increases in oxides of nitrogen (NOx). The largest decrease in PM emissions was achieved with the 15 percent DMM blend. On average, over the 13 test points, the DMM blend reduced PM emissions by 52 percent in comparison to the baseline diesel fuel.

The paper highlights the use of a light duty axle efficiency test for evaluating the fuel economy performance of automotive gear lubricants. Both final peak axle temperatures and torque efficiencies are recorded for several multigrade automotive gear lubricants. The dependence of temperature on torque efficiencies for the gear lubricants tested are discussed for a variety of driving conditions: city, highway and severe service. Temperature and torque efficiency data show strong dependence on additive system and viscosity- temperature characteristics of the gear lubricants under different driving conditions. A discussion of lubricant rheology and its importance to maintaining film strength for adequate bearing and gear lubrication as related to optimum torque efficiency and axle temperature under varying loads and pinion speeds is also provided.

The Office of Heavy Vehicle Technologies supports research to enable high-efficiency diesel engines to meet future emissions regulations, thus clearing the way for their use in light trucks as well as continuing as the most efficient powerplant for freight-haulers. Compliance with Tier 2 rules and expected heavy duty engine standards will require effective exhaust emission controls (aftertreatment) for diesels in these applications. DOE laboratories are working with industry to improve emission control technologies in projects ranging from application of new diagnostics for elucidating key mechanisms, to development and tests of prototype devices. This paper provides an overview of these R&D efforts, with examples of key findings and developments.

Detroit Diesel Corporation (DDC) is developing the DELTA 4.0L V6 engine, specifically for the North American light truck market. This market poses unique requirements for a diesel engine, necessitating a clean sheet engine design. DELTA was developed from a clean sheet of paper, with the first engine firing just 228 days later. The process began with a Quality Function Deployment (QFD) analysis, which prioritized the development criteria. The development process integrated a co-located, fully cross-functional team. Suppl iers were fully integrated and maintained on-site representation. The first demonstration vehicle moved under its own power 12 weeks after the first engine fired. It was demonstrated to the automotive press 18 days later. DELTA has repeatedly demonstrated its ability to disprove historical North American diesel perceptions and compete directly with gasoline engines. This paper outlines the Generation 0.0 development process and briefly defines the engine.

The Heavy Vehicle Propulsion Materials Program was begun in 1997 to support the enabling materials needs of the DOE Office of Heavy Vehicle Technologies (OHVT). The technical agenda for the program grew out of the technology roadmap for the OHVT and includes efforts in materials for: fuel systems, exhaust aftertreatment, valve train, air handling, structural components, electrochemical propulsion, natural gas storage, and thermal management. A five-year program plan was written in early 2000, following a stakeholders workshop. The technical issues and planned and ongoing projects are discussed. Brief summaries of several technical highlights are given.

The objectives of this paper are to describe the research efforts in diesel engine combustion at Sandia National Laboratories' Combustion Research Facility and to provide recent experimental results. We have four diesel engine experiments supported by the Department of Energy, Office of Heavy Vehicle Technologies: a one-cylinder version of a Cummins heavy-duty engine, a diesel simulation facility, a one-cylinder Caterpillar engine to evaluate combustion of alternative fuels, and a homogeneous-charge, compression-ignition (HCCI) engine facility is under development. Recent experimental results to be discussed are: the effects of injection timing and diluent addition on late-combustion soot burnout, diesel-spray ignition and premixed-burn behavior, a comparison of the combustion characteristics of M85 (a mixture of 85% methanol and 15% gasoline) and DF2 (#2 diesel reference fuel), and a description of our HCCI experimental program and modeling work.

The development of the Advanced Restraint System has lead to an innovative way in which we evaluate the systems effect on the occupant. This paper presents some initial investigation into the driver airbag system that consists of an inflator, cushion fold, tear seam pattern, and offset of the airbag cover to steering wheel rim plane. An initial DOE is reviewed to establish significant parameters and to identify equations for further investigation.

Natural gas is an attractive fuel for vehicles because it is a relatively clean-burning fuel compared with gasoline. Moreover, methane can be stored in the physically adsorbed state [at a pressure of 3.5 MPa (500 psi)] at energy densities comparable to methane compressed at 24.8 MPa (3600 psi). Here we report the development of natural gas storage monoliths [1]. The monolith manufacture and activation methods are reported along with pore structure characterization data. The storage capacities of these monoliths are measured gravimetrically at a pressure of 3.5 MPa (500 psi) and ambient temperature, and storage capacities of >150 V/V have been demonstrated and are reported.

It is well known that hydrogen addition to spark-ignited (SI) engines can reduce exhaust emissions and increase efficiency. Micro plasmatron fuel converters can be used for onboard generation of hydrogen-rich gas by partial oxidation of a wide range of fuels. These plasma-boosted microreformers are compact, rugged, and provide rapid response. With hydrogen supplement to the main fuel, SI engines can run very lean resulting in a large reduction in nitrogen oxides (NOx) emissions relative to stoichiometric combustion without a catalytic converter. This paper presents experimental results from a microplasmatron fuel converter operating under variable oxygen to carbon ratios. Tests have also been carried out to evaluate the effect of the addition of a microplasmatron fuel converter generated gas in a 1995 2.3-L four-cylinder SI production engine. The tests were performed with and without hydrogen-rich gas produced by the plasma boosted fuel converter with gasoline.

The WorldSID project is a global effort to design a new generation side impact crash test dummy under the direction of the International Organization for Standardization (ISO). The first WorldSID crash dummy will represent a world-harmonized mid-size adult male. This paper discusses the research and rationale undertaken to define the anthropometry of a world standard midsize male in the typical automotive seated posture. Various anthropometry databases are compared region by region and in terms of the key dimensions needed for crash dummy design. The Anthropometry for Motor Vehicle Occupants (AMVO) dataset, as established by the University of Michigan Transportation Research Institute (UMTRI), is selected as the basis for the WorldSID mid-size male, updated to include revisions to the pelvis bone location. The proposed mass of the dummy is 77.3kg with full arms. The rationale for the selected mass is discussed. The joint location and surface landmark database is appended to this paper.

The Automotive Market in the United States is moving in the direction of more Light Trucks and fewer Small Cars. The customers for these vehicles have not changed, only their purchase decisions. Cummins has studied the requirements of this emerging market. Design and development of an engine system that will meet these customer needs has started. The engine system is a difficult one, since the combined requirements of a very fuel-efficient commercial diesel, and the performance and sociability requirements of a gasoline engine are needed. Results of early testing are presented which show that the diesel is possibly a good solution.

The U.S. Environmental Protection Agency initiated a program to demonstrate feasibility of the Tier 2 emissions standards for the largest vehicles regulated under the new standards. Advanced emission control systems were developed and evaluated using a large 1999 sport utility vehicle and a large 1999 light-duty pickup truck. The trucks were originally certified to California LEV-I or Federal Tier 1 emission standards. Advanced, high-cell density, ceramic and metallic substrate three-way catalysts were thermally aged to the equivalent of 80,000 km (50,000 miles) and integrated into the exhaust systems for evaluation. Low mass, thermally insulated exhaust system components were fabricated and evaluated. Engine control strategies were modified via ROM-emulation and powertrain control module (PCM) flash reprogramming. Both of the tested trucks demonstrated FTP emissions at levels below 2004 U.S Federal Tier 2 emissions standards.

The Diesel Emission Control - Sulfur Effects (DECSE) program is a joint U.S. government/industry program that studies the impact of diesel sulfur levels on four types of emission control systems. One type of system, Diesel Particulate Filters (DPF), removes particulate matter (PM) from the exhaust stream by collection on a filter. The critical operating issue for DPF technology is the cleaning or regeneration of the control device (by oxidation of the collected PM) to prevent plugging. However, oxidation of sulfur in the exhaust forms sulfates, which are measured as PM. Two types of tests are conducted to evaluate the impacts of fuel sulfur on DPF performance: (1) emissions tests for PM components and gases, and (2) experiments to measure the effect of fuel sulfur on the regeneration temperature required by the filter devices.

With the ever-increasing stringency of emissions regulations, automotive three-way catalysts (TWCs) require much faster light-off performance and higher warmed-up activity than before. Most automotive manufacturers are considering the adoption of close-coupled catalyst systems as a means of dealing with cold start emissions and need the catalyst to have improved thermal durability. In this paper, a new Pd/Rh is reported to be suitable for high temperature application. Due to the recent increasing Pd metal cost, a Pt/Rh with equivalent or better TWC performance needs be developed to balance the PGM usage. A current Pt/Rh catalyst seems to possess comparable TWC performance to the new Pd/Rh catalyst when the catalysts are aged at 900°C. However, aging at a temperature higher than 900°C significantly deactivated the activity of the Pt/Rh catalyst to a point that is much worse than the Pd/Rh catalyst.

A study of statistical optimization of engine operating parameters was conducted. The objective of the study was to develop a strategy to efficiently optimize operating parameters of diesel engines with multiple injection and EGR capabilities. Previous studies have indicated that multiple injections with EGR can provide substantial simultaneous reductions in emissions of particulate and NOx from heavy-duty diesel engines, but careful optimization of the operating parameters is necessary in order to receive the full benefit of these combustion control techniques. The goal of the present study was to optimize the control parameters to reduce emissions and brake specific fuel consumption. An instrumented single-cylinder heavy-duty diesel engine was used with a prototype mechanically actuated (cam driven) fuel injection system.

An alternative approach is presented for the regression of response data on predictor variables that are not logically or physically separable. The methodology is demonstrated by its application to a data set of heavy-duty diesel emissions. Because of the covariance of fuel properties, it is found advantageous to redefine the predictor variables as vectors, in which the original fuel properties are components, rather than as scalars each involving only a single fuel property. The fuel property vectors are defined in such a way that they are mathematically independent and statistically uncorrelated. The available data set is not considered adequate for the development of a full-fledged emission model. Nevertheless, the data clearly show that only a few basic patterns of fuel-property variation affect emissions and that the number of these patterns is considerably less than the number of variables initially thought to be involved.

This study compares emissions test results among seven compressed natural gas and seven standard gasoline 1996 Ford Crown Victoria taxi cabs. The study applies a mixed-effects analysis of covariance (ANCOVA) model on data from three rounds of high-mileage emissions tests performed at target odometer readings of 60,000, 90,000, and 120,000 miles (i.e., 96,540, 144,810, and 193,080 km). The ANCOVA model describes emissions deterioration within each vehicle sample, while also accounting for individual vehicle variability within the sample. The model was used to determine whether there are statistically significant differences between each fuel's emissions profiles and deterioration rates over the mileage range studied. Results are reported for non-methane hydrocarbons, carbon monoxide, oxides of nitrogen, carbon dioxide, formaldehyde, and fuel economy.