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Viewing 1 to 30 of 261
2015-04-14
Technical Paper
2015-01-0972
Alexander Pawlowski, Derek Splitter
It is well known that spark ignited engine performance and efficiency is closely coupled to fuel octane number. The present work combines historical and recent trends in spark ignition engines to build a database of engine design, performance, and fuel octane requirements over the past 70 years. The database consists of engine compression ratio, required fuel octane number, peak mean effective pressure, specific output, and combined fuel economy for passenger vehicles and light trucks. Recent trends in engine performance, efficiency, and fuel octane number requirement were used to develop correlations of fuel octane number utilization, performance, specific output, and theoretical Otto cycle engine efficiency. The results show that historically, engine compression ratio, performance, and efficiency have been strongly coupled to fuel octane number.
2015-04-14
Technical Paper
2015-01-1008
Vitaly Y. Prikhodko, Josh A. Pihl, Todd J. Toops, John F. Thomas, James E. Parks, Brian H. West
Ethanol is a very effective reductant for nitrogen oxides (NOX) over silver/alumina (Ag/Al2O3) catalysts in lean exhaust environments. With the widespread availability of ethanol/gasoline-blended fuel in the U.S., lean gasoline engines equipped with Ag/Al2O3 catalysts have the potential to deliver higher fuel economy than stoichiometric gasoline engines and to increase biofuel utilization while meeting exhaust emissions regulations. In this work a pre-commercial 2 wt% Ag/Al2O3 catalyst was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine for the selective catalytic reduction (SCR) of NOX with ethanol/gasoline blends. The ethanol/gasoline blends were delivered via in-pipe injection upstream of the Ag/Al2O3 catalyst with the engine operating under lean conditions. A number of engine conditions were chosen to provide a range of temperatures and space velocities for evaluation of catalyst performance.
2015-04-14
Technical Paper
2015-01-0741
Derek Splitter, Barry Burrows, Sam Lewis
The present study consists of proof of concept level experiments of direct measurements and detailed chemical speciation of the liquid from the top ring zone of a running engine. The work uses a naturally aspirated single cylinder air-cooled utility engine that has been modified to allow direct liquid sample extraction from behind the top ring. Acquired samples were analyzed and spectated using gas chromatography analysis. Results show that the liquid mixture in the top ring zone is neither neat lubricant nor fuel but a combination of the two with unique chemical properties. At the tested steady state no load operating condition, the chemical species of the unique top ring zone liquid are shown to be species dependent, where both low reactivity higher boiling point aromatic fuel species and lubricant are observed to be the dominant constituents.
2015-04-14
Journal Article
2015-01-0855
Adam B. Dempsey, Scott Curran, Rolf D. Reitz
The focus of the present study was to characterize Reactivity Controlled Compression Ignition (RCCI) using a single-fuel approach of gasoline and gasoline mixed with a commercially available cetane improver on a multi-cylinder engine. RCCI was achieved by port injecting a certification grade 96 research octane gasoline and direct injecting the same gasoline mixed with various levels of the cetane improver, 2-ethylhexyl nitrate (EHN). The EHN volume percentage in the direct injected fuel was 10%, 5%, and 2.5%. The engine performance and emissions of the different fueling combinations was characterized at 2300 rpm and 4.2 bar BMEP over a various parametric investigations. Comparisons were made to gasoline/diesel operation on the same engine platform. The experiments were conducted on a four cylinder General Motors 1.9L ZDTH engine that has been modified with a port-fuel injection system while maintaining the stock direct injection fuel system.
2015-04-14
Journal Article
2015-01-0860
Michael Bergin, Adam Dempsey, Scott Curran, Rolf D. Reitz, Christopher Rutland
Abstract A novel 2-zone combustion system was examined at medium load operation consistent with loads in the light duty vehicle drive cycle (7.6 bar BMEP and 2600 rev/min). Pressure rise rate and noise can limit the part of the engine map where pre-mixed combustion strategies such as HCCI or RCCI can be used. The present 2-zone pistons have an axial projection that divides the near TDC volume into two regions (inner and outer) joined by a narrow communication channel defined by the squish height. Dividing the near TDC volume provides a means to prepare two fuel-air mixtures with different ignition characteristics. Depending on the fuel injection timing, the reactivity of the inner or outer volume can be raised to provide an ignition source for the fuel-air mixture in the other, less reactive volume. Multi-dimensional CFD modeling was used to design the 2-zone piston geometry examined in this study.
2015-04-14
Journal Article
2015-01-1022
Jinyong Luo, Hongmei An, Krishna Kamasamudram, Neal Currier, Aleksey Yezerets, Thomas Watkins, Larry Allard
Abstract In this contribution, nuanced changes of a commercial Cu-SSZ-13 catalyst with hydrothermal aging, which have not been previously reported, as well as their corresponding impact on SCR functions, are described. In particular, a sample of Cu-SSZ-13 was progressively aged between 550 to 900°C and the changes of performance in NH3 storage, oxidation functionality and NOx conversion of the catalyst were measured after hydrothermal exposure at each temperature. The catalysts thus aged were further characterized by NH3-TPD, XRD and DRIFTS techniques for structural changes. Based on the corresponding performance and structural characteristics, three different regimes of hydrothermal aging were identified, and tentatively as assigned to “mild”, “severe” and “extreme” aging. Progressive hydrothermal aging up to 750°C decreased NOx conversion to a small degree, as well as NH3 storage and oxidation functions.
2015-04-14
Technical Paper
2015-01-0837
Reed Hanson, Shawn Spannbauer, Christopher Gross, Rolf D. Reitz, Scott Curran, John Storey, Shean Huff
In the current work, a series hybrid vehicle has been constructed that utilizes a dual-fuel, Reactivity Controlled Compression Ignition (RCCI) engine. The series hybrid vehicle used a 2009 Saturn Vue chassis and a 1.9 L turbo-diesel engine converted to operate with RCCI combustion. The engine was coupled to a 90 kW AC motor to act as an electrical generator to charge a 14.1 kW-hr lithium-ion traction battery pack which powered a 75 kW drive motor. Full vehicle testing was conducted on a chassis dynamometer at the Vehicle Emissions Research Laboratory at Ford Motor Company and the Vehicle Research Laboratory at Oak Ridge National Laboratory. For this work, the Environmental Protection Agency Highway Fuel Economy Test was performed using RCCI combustion with commercially available gasoline and ultra-low sulfur diesel. Fuel economy and emissions were recorded over the specified test cycle and calculated based on the fuel properties and high-voltage battery energy usage.
2015-04-14
Journal Article
2015-01-0888
Michael D. Kass, Chris Janke, Raynella Connatser, Sam Lewis, James Keiser, Timothy Theiss
Biologically derived fuel oil is being considered as a drop-in fuel to partially displace heavy fuels, especially diesel fuel. A matrix of polymer specimens representing those used in both fueling infrastructure and vehicle fuel delivery systems was exposed to neat No. 2 diesel fuel and a blend containing 20% bio-oil. Polymer types included both elastomer and plastic. Four specimens were evaluated for each material type (three immersed in the test fuel liquid and one placed exposed to the vapor phase only). For each specimen exposed to the liquid fuel, the mass and volume change and hardness were measured for both wetted and dried conditions. The specimens exposed to the vapor phase were measured for hardness only. Dynamic mechanical analysis was also performed for each material to determine the onset of the glass to rubber transition temperature. The results showed that the addition of bio-oil expanded the volume of the fluoroelastomers by up to 60%, which was dramatic.
2015-04-14
Journal Article
2015-01-0894
Michael D. Kass, Chris Janke, Timothy Theiss, James Baustian, Leslie Wolf, Wolf Koch
Plastic materials are used ubiquitously in fuel infrastructure systems. A matrix of plastic specimens including thermoplastics and thermosetting resins were exposed to test fuels representing neat gasoline and E10. Previously the research team had evaluated plastic materials in test fuels representing E0, E25, E50, and E85. The lack of information for a 10 percent ethanol blend has prevented accurate interpolation of performance of these materials at low blend levels. The test fuel was an aggressive formulation derived following the SAE J1681 protocol. Four specimens were evaluated for each material type (three immersed in the test fuel liquid and one placed exposed to the vapor phase only). For each specimen exposed to the liquid fuel, the mass and volume change and hardness were measured for both wetted and dried conditions. The specimens exposed to the vapor phase were measured for hardness only.
2015-04-14
Journal Article
2015-01-0893
Michael D. Kass, Chris Janke, Raynella Connatser, Sam Lewis, James Keiser, Timothy Theiss
Plastic materials are used ubiquitously in fuel infrastructure systems. A matrix of plastic specimens including thermoplastics and thermosetting resins were exposed to No. 2 diesel fuel and a blend containing 20% bio-oil. Material types included permeation barriers, (PET, PPS, PVDF, and PTFE), Nylon, acetals, polyethylene and several types of fiberglass resin, Four specimens were evaluated for each material type (three immersed in the test fuel liquid and one placed exposed to the vapor phase only). The exposure time for each material was 16 weeks at 60oC For each specimen exposed to the liquid fuel, the mass and volume change and hardness were measured for both wetted and dried conditions. The specimens exposed to the vapor phase were measured for hardness only. Dynamic mechanical analysis was also performed for each material to determine the onset of the glass to rubber transition temperature.
2015-01-15
Article
Oak Ridge National Laboratory (ORNL) had its latest 3-D printing technology at the North American International Auto Show in Detroit, showing off a replica of a classic Shelby Cobra made via the rapidly propagating technology.
2014-12-23
Article
The potential impact to public health from GDI engine particulates is driving new developments in fuel delivery, controls, and combustion strategies.
2014-12-17
Article
Claus Daniel, Ph.D., is Deputy Director for the Sustainable Transportation Program at Oak Ridge National Laboratory (ORNL), Founding Director of the U.S. Department of Energy Battery Manufacturing R&D Facility at ORNL.
2014-10-20
Article
Automakers are racing to cut the cost of lightweight materials that help boost fuel efficiency. In this week's SAE Eye on Engineering, Senior Editor Lindsay Brooke looks at the U.S. and German automakers' push for low-cost carbon fiber.
2014-10-13
Technical Paper
2014-01-2707
Brian C. Kaul, Benjamin J. Lawler, Charles E.A. Finney, Michelle L. Edwards, Robert M. Wagner
Abstract Advances in engine controls and sensor technology are making advanced, direct, high-speed control of engine combustion more feasible. Control of combustion rate and phasing in low-temperature combustion regimes and active control of cyclic variability in dilute SI combustion are being pursued in laboratory environments with high-quality data acquisition systems, using metrics calculated from in-cylinder pressure. In order to implement these advanced combustion controls in production, lower-quality data will need to be tolerated even if indicated pressure sensors become available. This paper examines the effects of several data quality issues, including phase shifting (incorrect TDC location), reduced data resolution, pressure pegging errors, and random noise on calculated combustion metrics that are used for control feedback.
2014-10-13
Journal Article
2014-01-2562
John Thomas
Abstract Vehicle manufacturers among others are putting great emphasis on improving fuel economy (FE) of light-duty vehicles in the U.S. market, with significant FE gains being realized in recent years. The U.S. Environmental Protection Agency (EPA) data indicates that the aggregate FE of vehicles produced for the U.S. market has improved by over 20% from model year (MY) 2005 to 2013. This steep climb in FE includes changes in vehicle choice, improvements in engine and transmission technology, and reducing aerodynamic drag, rolling resistance, and parasitic losses. The powertrain related improvements focus on optimizing in-use efficiency of the transmission and engine as a system, and may make use of what is termed downsizing and/or downspeeding. This study quantifies recent improvements in powertrain efficiency, viewed separately from other vehicle alterations and attributes (noting that most vehicle changes are not completely independent).
2014-09-30
Journal Article
2014-01-2326
Zhiming Gao, Charles Finney, Charles Daw, Tim J. LaClair, David Smith
Two hybrid powertrain configurations, including parallel and series hybrids, were simulated for fuel economy, component energy loss, and emissions control in Class 8 trucks over both city and highway driving conditions. A comprehensive set of component models describing engine fuel consumption, emissions control, battery energy, and accessory power demand interactions was developed and integrated with the simulated hybrid trucks to identify heavy-duty (HD) hybrid technology barriers. The results show that series hybrid is absolutely negative for fuel-economy improvement of long-haul trucks due to an efficiency penalty associated with the dual-step conversions of energy (i.e. mechanical to electric to mechanical).
2014-06-26
Article
The Department of Energy’s Oak Ridge National Laboratory (ORNL) has launched its new Institute for Functional Imaging of Materials, which aims to accelerate discovery, design, and deployment of new materials, according to a release from the laboratory.
2014-05-04
Article
A new electrolyte developed the U.S. Department of Energy's Oak Ridge National Laboratory (ORNL) serves not only as an ion conductor, but also as a cathode supplement in batteries. Potential uses of the technology include remote keyless entry systems, cardiac pacemakers, sensors, and other applications "where replacing or recharging a battery is not possible or desirable."
2014-04-01
Technical Paper
2014-01-1542
Krishna Kamasamudram, Ashok Kumar, Jinyong Luo, Neal Currier, Aleksey Yezerets, Thomas Watkins, Larry Allard
Abstract An operational challenge associated with SCR catalysts is the NH3 slip control, particularly for commercial small pore Cu-zeolite formulations as a consequence of their significant ammonia storage capacity. The desorption of NH3 during increasing temperature transients is one example of this challenge. Ammonia slipping from SCR catalyst typically passes through a platinum based ammonia oxidation catalyst (AMOx), leading to the formation of the undesired byproducts NOx and N2O. We have discovered a distinctive characteristic, an overlapping NH3 desorption and oxidation, in a state-of-the-art Cu-zeolite SCR catalyst that can minimize NH3 slip during temperature transients encountered in real-world operation of a vehicle.
2014-04-01
Technical Paper
2014-01-1673
Michael D. Kass, Mark W. Noakes, Brian Kaul, Dean Edwards, Timothy Theiss, Lonnie Love, Ryan Dehoff, John Thomas
Abstract The performance of a 4cc two-stroke single cylinder glow plug engine was assessed at wide open throttle for speeds ranging from 2000 to 7000RPM. The engine performance was mapped for the stock aluminum head and one composed of titanium, which was printed using additive manufacturing. The engine was mounted to a motoring dynamometer and the maximum torque was determined by adjusting the fuel flow. Maximum torque occurred around 3000 to 3500RPM and tended to be higher when using the aluminum head. At slower speeds, the titanium head produced slightly higher torque. For each test condition, maximum torque occurred at leaner conditions for the titanium head compared to the stock aluminum one. Higher efficiencies were observed with the aluminum head for speeds greater than 3000RPM, but the titanium heads provided better efficiency at the lower speed points.
2014-04-01
Technical Paper
2014-01-1965
Zhenhong Lin, Jan-Mou Li, Jing Dong
Abstract This study attempts to establish a quantitative linkage between deployment of dynamic wireless power transfer (DWPT) and the market adoption of plug-in electric vehicles (PEV). This linkage can be useful for analyzing the societal benefits of DWPT and justifying investments in its research, development, demonstration and deployment. Spatial relationships between charging opportunity and DWPT availability are estimated for four metropolitan areas. The consumer value of DWPT is formulated as a function of key DWPT deployment parameters and then integrated into an existing validated consumer choice model, where sales of PEVs are endogenous. Results indicate significant impacts on PEV sales of DWPT deployment, even only at 0.5% of road length by 2050. Significant impact heterogeneity is observed.
2014-04-01
Technical Paper
2014-01-0879
Jan-Mou Li, David Smith
Abstract Driver is a key component in vehicle simulation. An ideal driver model simulates driving patterns a human driver may perform to negotiate road profiles. There are simulation packages having the capability to simulate driver behavior. However, it is rarely documented how they work with road profiles. This paper proposes a new truck driver model for vehicle simulation to imitate actual driving behavior in negotiating road grade and curvature. The proposed model is developed based upon Gipps' car-following model. Road grade and curvature were not considered in the original Gipps' model although it is based directly on driver behavior and expectancy for vehicles in a stream of traffic. New parameters are introduced to capture drivers' choice of desired speeds that they intend to use in order to negotiating road grade and curvature simultaneously. With the new parameters, the proposed model can emulate behaviors like uphill preparation for different truck drivers.
2014-04-01
Technical Paper
2014-01-0343
Jing Dong, Zhenhong Lin, Changzheng Liu, Yanghe Liu
Abstract This paper utilizes GPS tracked multiday travel activities to estimate the temporal distribution of electricity loads and assess battery electric vehicle (BEV) grid impacts at a significant market penetration level. The BEV load and non-PEV load vary by time of the day and day of the week. We consider two charging preferences: home priority assumes BEV drivers prefer charging at home and would not charge at public charging stations unless the state of charge (SOC) of the battery is not sufficient to cover the way back to home; and charging priority does not require drivers to defer charging to home and assumes drivers will utilize the first available charging opportunity. Both home and charging priority scenarios show an evening peak demand. Charging priority scenario also shows a morning peak on weekdays, possibly due to workplace charging.
2014-04-01
Journal Article
2014-01-1562
Zhiming Gao, Tim J. LaClair, C. Stuart Daw, David E. Smith, Oscar Franzese
We present simulated fuel economy and emissions of city transit buses powered by conventional diesel engines and diesel-hybrid electric powertrains of varying size. Six representative city drive cycles were included in the study. In addition, we included previously published aftertreatment device models for control of CO, HC, NOx, and particulate matter (PM) emissions. Our results reveal that bus hybridization can significantly enhance fuel economy by reducing engine idling time, reducing demands for accessory loads, exploiting regenerative braking, and shifting engine operation to speeds and loads with higher fuel efficiency. Increased hybridization also tends to monotonically reduce engine-out emissions, but tailpipe (post-aftertreatment) emissions are affected by complex interactions between engine load and the transient catalyst temperatures, and the emissions results were found to depend significantly on motor size and details of each drive cycle.
2014-04-01
Journal Article
2014-01-1505
Vitaly Y. Prikhodko, James E. Parks, Josh A. Pihl, Todd J. Toops
A commercial three-way catalyst (TWC) was evaluated for ammonia (NH3) generation on a 2.0-liter BMW lean burn gasoline direct injection engine as a component in a passive ammonia selective catalytic reduction (SCR) system. The passive NH3 SCR system is a potential low cost approach for controlling nitrogen oxides (NOX) emissions from lean burn gasoline engines. In this system, NH3 is generated over a close-coupled TWC during periodic slightly rich engine operation and subsequently stored on an underfloor SCR catalyst. Upon switching to lean, NOX passes through the TWC and is reduced by the stored NH3 on the SCR catalyst. NH3 generation was evaluated at different air-fuel equivalence ratios at multiple engine speed and load conditions. Near complete conversion of NOX to NH3 was achieved at λ=0.96 for nearly all conditions studied. At the λ=0.96 condition, HC emissions were relatively minimal, but CO emissions were significant.
2014-04-01
Journal Article
2014-01-1614
John Thomas, Shean Huff, Brian West
To quantify the fuel economy (FE) effect of some common vehicle accessories or alterations, a compact passenger sedan and a sport utility vehicle (SUV) were subjected to SAE J2263 coastdown procedures. Coastdowns were conducted with low tire pressure, all windows open, with a roof top or hitch-mounted cargo carrier, and with the SUV pulling an enclosed cargo trailer. From these coastdowns, vehicle dynamometer coefficients were developed which enabled the execution of vehicle dynamometer experiments to determine the effect of these changes on vehicle FE and emissions over standard drive cycles and at steady highway speeds. In addition, two minivans were subjected to coastdowns to examine the similarity in derived coefficients for two duplicate vehicles of the same model. The FE penalty associated with the rooftop cargo box mounted on the compact sedan was as high as 25-27% at higher speeds, where the aerodynamic drag is most pronounced.
2014-04-01
Journal Article
2014-01-0818
Forrest Jehlik, Tim Laclair
Response surface methodology (RSM) techniques were applied to develop a predictive model of electric vehicle (EV) energy consumption over the Environmental Protection Agency's (EPA) standardized drive cycles. The model is based on measurements from a synthetic composite drive cycle. The synthetic drive cycle is a minimized statistical composite of the standardized urban (UDDS), highway (HWFET), and US06 cycles. The composite synthetic drive cycle is 20 minutes in length thereby reducing testing time of the three standard EPA cycles by over 55%. Vehicle speed and acceleration were used as model inputs for a third order least squared regression model predicting vehicle battery power output as a function of the drive cycle. The approach reduced three cycles and 46 minutes of drive time to a single test of 20 minutes.
2014-04-01
Journal Article
2014-01-1004
Sujit Das
Advanced lightweight materials are increasingly being incorporated into new vehicle designs by automakers to enhance performance and assist in complying with increasing requirements of corporate average fuel economy standards. To assess the primary energy and carbon dioxide equivalent (CO2e) implications of vehicle designs utilizing these materials, this study examines the potential life cycle impacts of two lightweight material alternative vehicle designs, i.e., steel and aluminum of a typical passenger vehicle operated today in North America. LCA for three common alternative lightweight vehicle designs are evaluated: current production (“Baseline”), an advanced high strength steel and aluminum design (“LWSV”), and an aluminum-intensive design (AIV). This study focuses on body-in-white and closures since these are the largest automotive systems by weight accounting for approximately 40% of total curb weight of a typical passenger vehicle.
2014-04-01
Journal Article
2014-01-1465
Michael D. Kass, Chris Janke, Timothy Theiss, Steve Pawel, James Baustian, Les Wolf, Wolf Koch
The compatibility of plastic materials used in gasoline storage and dispensing applications was determined for test fuels representing neat gasoline (Fuel C), and blends containing 25% ethanol (CE25a), 16% isobutanol (CiBu16a), and 24% isobutanol (CiBu24a). A solubility analysis was also performed and compared to the volume swell results obtained from the test fuel exposures. The plastic specimens were exposed to each test fuel for16 weeks at 60°C. After measuring the wetted volume and hardness, the specimens were dried for 65 hours at 60°C and then remeasured for volume and hardness. Dynamic mechanical analysis (DMA), which measures the storage modulus as a function of temperature, was also performed on the dried specimens to determine the temperature associated with the onset of the glass-to-rubber transition (Tg). For many of the plastic materials, the solubility analysis was able to predict the relative volume swell for each test fuel.
Viewing 1 to 30 of 261

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