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Video

Dynamometer Evaluation of Five Electric Vehicles Designed for Urban Deliver Route Services ?

2011-11-21
With nearly 220,000 vehicles, the United States Postal Service (USPS) has the largest non-military vehicle fleet in the world. This fleet requires over a billion dollars of fuel annually, and this figure does not include contracted vehicles. As a part of the business strategy, the USPS has embraced and invested in alternative fueled vehicles since 1899, when the first recorded use of an electric vehicle for USPS service was performed as a technology evaluation in Cleveland, OH. As part of a technology evaluation of advanced vehicle systems, the USPS has partnered with the DOE?s Vehicle Technology Program (VTP) to benchmark and quantify the capabilities of five vehicles in meeting specific Urban Route Delivery requirements, both with dynamometer and in-service testing. The all electric vehicle conversions have been developed by established electric vehicle systems manufacturers representing various perspectives on meeting the vehicle specific operation objectives.
Video

Consumer Behavior and Risk Aversion

2011-11-04
Auto manufacturers have known and surveys confirm that consumers require short payback periods (2-4 years) for investments in fuel economy. Using societal discount rates, engineering-economic generally find substantial potential to increase fuel economy, cost-effectively. This phenomenon, often referred to as the ?energy paradox?, has been observed in nearly all consumers? choices of energy-using durable goods. Loss aversion, perhaps the most well established theory of behavioral economics, provides a compelling explanation. Engineering economic analyses generally overlook the fact that consumers? investments in fuel economy are not sure things but rather risky bets. Future energy prices, real world on-road fuel economy, and many other factors are uncertain. Loss aversion describes a fundamental human tendency to exaggerate the potential for loss relative to gain when faced with a risky bet. It provides a sufficient explanation for consumers?
Video

Hydrocarbon Fouling of SCR During PCCI Combustion

2012-06-18
The combination of advanced combustion with advanced selective catalytic reduction (SCR) catalyst formulations was studied in the work presented here to determine the impact of the unique hydrocarbon (HC) emissions from premixed charge compression ignition (PCCI) combustion on SCR performance. Catalyst core samples cut from full size commercial Fe- and Cu-zeolite SCR catalysts were exposed to a slipstream of raw engine exhaust from a 1.9-liter 4-cylinder diesel engine operating in conventional and PCCI combustion modes. The zeolites which form the basis of these catalysts are different with the Cu-based catalyst made on a chabazite zeolite which las smaller pore structures relative to the Fe-based catalyst. Subsequent to exposure, bench flow reactor characterization of performance and hydrocarbon release and oxidation enabled evaluation of overall impacts from the engine exhaust.
Video

Ionic Liquids as Novel Lubricants or Lubricant Additives

2012-05-10
For internal combustion engines and industrial machinery, it is well recognized that the most cost-effective way of reducing energy consumption and extending service life is through lubricant development. This presentation summarizes our recent R&D achievements on developing a new class of candidate lubricants or oil additives ionic liquids (ILs). Features of ILs making them attractive for lubrication include high thermal stability, low vapor pressure, non-flammability, and intrinsic high polarity. When used as neat lubricants, selected ILs demonstrated lower friction under elastohydrodynamic lubrication and less wear at boundary lubrication benchmarked against fully-formulated engine oils in our bench tests. More encouragingly, a group of non-corrosive, oil-miscible ILs has recently been developed and demonstrated multiple additive functionalities including anti-wear and friction modifier when blended into hydrocarbon base oils.
Technical Paper

A Life-Cycle-Based Environmental Evaluation: Materials in New Generation Vehicles

2000-03-06
2000-01-0595
This project team conducted a life-cycle-based environmental evaluation of new, lightweight materials (e.g., titanium, magnesium) used in two concept 3XVs -- i.e., automobiles that are three times more fuel efficient than today's automobiles -- that are being designed and developed in support of the Partnership for a New Generation of Vehicles (PNGV) program. The two concept vehicles studied were the DaimlerChrysler ESX2 and the Ford P2000. Data for this research were drawn from a wide range of sources, including: the two automobile manufacturers; automobile industry reports; government and proprietary databases; past life-cycle assessments; interviews with industry experts; and models.
Technical Paper

Graphitic Foam Thermal Management Materials for Electronic Packaging

2000-04-02
2000-01-1576
The goal of this program is to utilize the recently developed high conductivity carbon foam for thermal management in electronics (heat exchangers and heat sinks). The technique used to fabricate the foam produces mesophase pitch-based graphitic foam with extremely high thermal conductivity and an open-celled structure. The thermal properties of the foam have been increased by 79% from 106 to 187 W/m·K at a density of 0.56 g/cm3 through process optimization. It has been demonstrated that when the high-thermal-conductivity graphitic foam is utilized as the core material for the heat exchanger, the effective heat transfer can be increased by at least an order of magnitude compared to traditional designs. A once-through-foam core/aluminum-plated heat exchanger has been fabricated for testing in electronic modules for power inverters.
Technical Paper

Test Methodologies for Determining Energy Absorbing Mechanisms of Automotive Composite Material Systems

2000-04-02
2000-01-1575
Composite materials have the potential to reduce the overall cost and weight of automotive structures with the added benefit of being able to dissipate large amounts of impact energy by progressive crushing. To identify and quantify the energy absorbing mechanisms in composite materials, test methodologies were developed for conducting progressive crush tests on composite specimens that have simplified test geometries. The test method development focused on isolating the damage modes associated with the frond formation that occurs in dynamic testing of composite tubes. A new test fixture was designed to progressively crush composite plate specimens under quasi-static test conditions. Preliminary results are presented under a sufficient set of test conditions to validate the operation of the test fixture.
Technical Paper

A Machine Approach for Field Weakening of Permanent-Magnet Motors

2000-04-02
2000-01-1549
The commonly known technology of field weakening for permanent-magnet (PM) motors is achieved by controlling the direct-axis current component through an inverter. Without using mechanical variation of the air gap, a new machine approach for field weakening of PM machines by direct control of air-gap fluxes is introduced. The demagnetization situation due to field weakening is not an issue with this new method. In fact, the PMs are strengthened at field weakening. The field-weakening ratio can reach 10:1 or higher. This technology is particularly useful for the PM generators and electric vehicle drives.
Technical Paper

Life-Cycle Cost Sensitivity to Battery-Pack Voltage of an HEV

2000-04-02
2000-01-1556
A detailed component performance, ratings, and cost study was conducted on series and parallel hybrid electric vehicle (HEV) configurations for several battery pack and main electric traction motor voltages while meeting stringent Partnership for a New Generation of Vehicles (PNGV) power delivery requirements. A computer simulation calculated maximum current and voltage for each component as well as power and fuel consumption. These values defined the peak power ratings for each HEV drive system's electric components: batteries, battery cables, boost converter, generator, rectifier, motor, and inverter. To identify a superior configuration or voltage level, life cycle costs were calculated based on the components required to execute simulated drive schedules. These life cycle costs include the initial manufacturing cost of components, fuel cost, and battery replacement cost over the vehicle life.
Technical Paper

Model-based Generation of Scaling Laws for Radial-Gap Permanent Magnet Motors

2000-04-02
2000-01-1570
Oak Ridge National Laboratory's (ORNL) computer code PMM_IDT (Permanent Magnet Motor Interactive Design Tool) was used to study the sensitivity to changes in design parameters at constant power output and scaling laws for similar designs with different rated power outputs. The base design used was a radial-gap motor with 30 kW of net output characteristic of the PNGV “Series” vehicles. Sensitivity parameters studied were active length, magnet and air gap thicknesses, and number of magnets. Power output variation approaches considered were active length, stator external diameter, and rotor external diameter. The impact on efficiency, cost, weight, specific power, cooling requirements, drive current and voltage requirements, and demagnetization margins are presented. Common constraints in this study are: Hollow rotor, trapezoidal back emf - 212 V maximum - and double layer winding leading to an even number of turns per slot
Technical Paper

Manufacturing of Carbon Fibers Using Microwave-Assisted Plasma Technology

2000-04-02
2000-01-1527
The most significant obstacle to the widespread use of carbon-fiber-based composites by the automotive industry is the high cost of carbon fibers in comparison to other potential structural materials. Carbon fibers are currently produced by thermal pyrolysis of a polyacrylonitrile (PAN) precursor to obtain the desired properties. The most significant cost factors in the process are the high cost of precursors and the high capital equipment and energy costs in conversion to carbon fiber. The Department of Energy is supporting developmental efforts to reduce costs in both precursor production and conversion areas. This paper describes developments in the conversion process. Because of the unsuccessful results of manufacturing carbon fibers through their direct heating with microwave radiation (variable frequency microwave [VFM] and single frequency microwave [SFM] energy), new avenues were explored for this processing.
Technical Paper

Evaluation of Large Tow-Size Carbon Fiber for Reducing the Cost of CNG Storage Tanks

2000-04-02
2000-01-1526
The performance of large tow-size carbon fiber was evaluated to determine any design impacts that would prohibit their introduction into the fabrication process of compressed natural gas (CNG) storage tanks. The evaluation was based on manufacturing process trials and mechanical property tests. The tests consisted of impregnated strand, composite ring, and composite subscale cylinder tests for static strength, fatigue, and stress rupture. Modifications required in the wet-filament winding process are documented as well as the development of test methodologies required for testing large tow-size impregnated strands.
Technical Paper

In-Situ Mechanical Property Evaluation of Dielectric Ceramics in Multilayer Capacitors

2000-04-02
2000-01-1535
The Young's modulus, hardness, and fracture toughness of barium titanate dielectric ceramics in three commercially available multilayer capacitors (MLCs) were measured in-situ using indentation and a mechanical properties microprobe. The three MLCs were equivalent in size (0805), capacitance (0.1 μF) and dielectric type (X7R). The Young's modulus and hardness of the dielectric ceramics in the three MLCs were similar, while there were statistically significant differences in their fracture toughnesses. The results provide insight into the assessment of MLC mechanical reliability, and show that equivalent electrical MLC rating is not necessarily a guarantee that the dielectric ceramics in them will exhibit equivalent mechanical performance.
Technical Paper

Time Irreversibility and Comparison of Cyclic-Variability Models

1999-03-01
1999-01-0221
We describe a method for detecting and quantifying time irreversibility in experimental engine data. We apply this method to experimental heat-release measurements from four spark-ignited engines under leaning fueling conditions. We demonstrate that the observed behavior is inconsistent with a linear Gaussian random process and is more appropriately described as a noisy nonlinear dynamical process.
Technical Paper

Mode I Fracture Testing of Adhesively Bonded Joints

1999-03-01
1999-01-1253
Several standard methods exist for testing composites, metals and plastics in Mode I fracture. However, these standard test methods have limitations that disqualify them as candidates for testing certain automotive materials. In order to conduct successful fracture toughness tests with these automotive materials, a modified double cantilever beam testing geometry and associated new procedure have been developed. Both the test procedure and the data analysis have been fully documented in a draft standard. Representative SRIM composite, e-coat steel and epoxy were selected to develop and validate the testing procedure.
Technical Paper

Exhaust Chemistry of Low-NOX, Low-PM Diesel Combustion

2004-03-08
2004-01-0114
The exhaust chemistry of combustion regimes characterized by simultaneous low-NOX and low-PM emissions were investigated on a Mercedes 1.7-L diesel engine. Two approaches for entering low-NOX low-PM regimes were explored using a California specification low aromatic certification diesel fuel. Detailed characterizations of gas-phase hydrocarbons, particulate soluble organics, and aldehydes are presented for both approaches. Results indicate significant formation of partially oxygenated hydrocarbons and fuel reformation products during periods of low-NOX, low-PM combustion.
Technical Paper

Selective Catalytic Reduction of NOx Emissions from a 5.9 Liter Diesel Engine Using Ethanol as a Reductant

2003-10-27
2003-01-3244
NOx emissions from a heavy-duty diesel engine were reduced by more than 90% and 80% utilizing a full-scale ethanol-SCR system for space velocities of 21000/h and 57000/h respectively. These results were achieved for catalyst temperatures between 360 and 400°C and for C1:NOx ratios of 4-6. The SCR process appears to rapidly convert ethanol to acetaldehyde, which subsequently slipped past the catalyst at appreciable levels at a space velocity of 57000/h. Ammonia and N2O were produced during conversion; the concentrations of each were higher for the low space velocity condition. However, the concentration of N2O did not exceed 10 ppm. In contrast to other catalyst technologies, NOx reduction appeared to be enhanced by initial catalyst aging, with the presumed mechanism being sulfate accumulation within the catalyst. A concept for utilizing ethanol (distilled from an E-diesel fuel) as the SCR reductant was demonstrated.
Technical Paper

A Comparative Assessment of Alternative Powertrains and Body-in-White Materials for Advanced Technology Vehicles

2004-03-08
2004-01-0573
The affordability of today's and future advanced technology vehicles (i.e., diesel, hybrid, and fuel cell) developed for improved fuel economy remains a concern with respect to final consumer acceptance. The automotive system cost model (ASCM) developed for the production cost estimates at a level of five major subsystems and 35+ components, has been used here to address the affordability issue of advanced technology vehicles. Scenarios encompassing five alternative powertrain and three body options for a mid-size vehicle under two different timeframes (i.e., 2002 and 2010) were considered to determine the cost-effectiveness of among the competing technology options within the same timeframe and between the two timeframes.
Technical Paper

Modeling of Strain Rate Effects in Automotive Impact

2003-03-03
2003-01-1383
This paper deals with the effects of various approaches for modeling of strain rate effects for mild and high strength steels (HSS) on impact simulations. The material modeling is discussed in the context of the finite element method (FEM) modeling of progressive crush of energy absorbing automotive components. The characteristics of piecewise linear plasticity strain rate dependent material model are analyzed and various submodels for modeling of impact response of steel structures are investigated. The paper reports on the ranges of strains and strain rates that are calculated in typical FEM models for tube crush and their dependence on the material modeling approaches employed. The models are compared to the experimental results from drop tower tests.
Technical Paper

Emission Performance of Selected Biodiesel Fuels

2003-05-19
2003-01-1866
Because of the great interest in biodiesel fuels around the world, the International Energy Agency's Committee on Advanced Motor Fuels sponsored this project to determine emissions and performance of a number of biodiesel fuels with a special emphasis on unregulated emissions. Oak Ridge National Laboratory (ORNL) and Technical Research Centre in Finland (VTT) carried out the project with complementary work plans. Several different engines were used between the two sites, and in some cases emissions control catalysts were used, both at ORNL and at VTT. ORNL concentrated on light and medium duty engines, while VTT emphasized a heavy-duty engine and also used a light duty car as a test bed. Common fuels between the two sites for these tests were rape methyl ester in 30% blend and neat, soy methyl ester in 30% blend and neat, used vegetable oil methyl ester (UVOME) in 30% blend, and the Swedish environmental class 1 reformulated diesel (RFD).
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