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This paper reports the development of new fuel ignition quality and combustion experiments performed using the Ignition Quality Tester (IQT). Prior SAE papers (961182, 971636, 1999-01-3591, and 2001-01-3527) documented the development of the IQT constant volume combustion chamber experimental apparatus to measure ignition qualities of diesel-type fuels. The ASTM International test method D6890 was developed around the IQT device to allow the rapid determination of derived cetane number (DCN). Interest in chemical kinetic models for the ignition of diesel and biodiesel model compounds is increasing to support the development of advanced engines and fuels. However, rigorous experimental validation of these kinetic models has been limited for a variety of reasons. Shock tubes and rapid compression machines are typically limited to premixed gas-phase studies, for example.

It is estimated that operating continuously on a B20 fuel containing the current allowable ASTM specification limits for metal impurities in biodiesel could result in a doubling of ash exposure relative to lube-oil-derived ash. The purpose of this study was to determine if a fuel containing metals at the ASTM limits could cause adverse impacts on the performance and durability of diesel emission control systems. An accelerated durability test method was developed to determine the potential impact of these biodiesel impurities. The test program included engine testing with multiple DPF substrate types as well as DOC and SCR catalysts. The results showed no significant degradation in the thermo-mechanical properties of cordierite, aluminum titanate, or silicon carbide DPFs after exposure to 150,000 mile equivalent biodiesel ash and thermal aging. However, exposure of a cordierite DPF to 435,000 mile equivalent aging resulted in a 69% decrease in the thermal shock resistance parameter.

The air-conditioning (A/C) compressor load significantly impacts the fuel economy of conventional vehicles and the fuel use/range of plug-in hybrid electric vehicles (PHEV). A National Renewable Energy Laboratory (NREL) vehicle performance analysis shows the operation of the air conditioner reduces the charge depletion range of a 40-mile range PHEV from 18% to 30% in a worst case hot environment. Designing for air conditioning electrical loads impacts PHEV and electric vehicle (EV) energy storage system size and cost. While automobile manufacturers have climate control procedures to assess A/C performance, and the U.S. EPA has the SCO3 drive cycle to measure indirect A/C emissions, there is no automotive industry consensus on a vehicle level A/C fuel use test procedure. With increasing attention on A/C fuel use due to increased regulatory activities and the development of PHEVs and EVs, a test procedure is needed to accurately assess the impact of climate control loads.

Hydrogen fuel cell vehicles (FCVs) appear to be a promising solution for the future of clean and efficient personal transportation. Issues of how to generate the hydrogen and then store it on-board to provide satisfactory driving range must still be resolved before they can compete with conventional vehicles. Alternatively, FCVs could obtain hydrogen from on-board reforming of gasoline or other fuels such as methanol or ethanol. On-board reformers convert fuel into a hydrogen-rich fuel stream through catalytic reactions in several stages. The high temperatures associated with fuel processing present an engineering challenge to warm up the reformer quickly and efficiently in a vehicle environment. Without a special warmup phase or vehicle hybridization, the reformer and fuel cell system must provide all power to move the vehicle, including ¼ power in 30 s, and ½ power in 3 min to satisfy the Federal Test Procedure (FTP) cycle demands.

The National Renewable Energy Laboratory (NREL) collaborated with Millennium Cell and DaimlerChrysler to study heat and water management in a sodium borohydride (NaBH4) storage/processor used to supply hydrogen to a fuel cell in an automotive application. Knowledge of heat and water flows in this system is necessary to maximize the storage concentration of NaBH4, which increases vehicle range. This work helps evaluate the NaBH4 system's potential to meet the FreedomCAR program technical target of 6 wt% hydrogen for hydrogen storage technologies. This paper also illustrates the advantages of integrating the NaBH4 hydrogen processor with the fuel cell.

The exhaust emissions from a single-cylinder version of a heavy-duty diesel engine with exhaust gas recirculation (EGR) were studied using 12 diesel fuels derived from oil sands and conventional sources. The test fuels were blended from 22 refinery streams to produce four fuels (two from each source) at three different total aromatic levels (10, 20, and 30% by mass). The cetane numbers were held constant at 43. Exhaust emissions were measured using the AVL eight-mode steady-state test procedure. PM emissions were accurately modeled by a single regression equation with two predictors, total aromatics and sulphur content. Sulphate emissions were found to be independent of the type of sulphur compound in the fuel. NOx emissions were accurately modeled by a single regression equation with total aromatics and density as predictor variables. PM and NOx emissions were significantly significantly affected by fuel properties, but crude oil source did not play a role.

An ADVISOR model of a large sport utility vehicle with a fuel cell / battery hybrid electric drivetrain is developed using validated component models. The vehicle mass, electric traction drive, and total net power available from fuel cells plus batteries are held fixed. Results are presented for a range of fuel cell size from zero (pure battery EV) up to a pure fuel cell vehicle (no battery storage). The fuel economy results show that some degree of hybridization is beneficial, and that there is a complex interaction between the drive cycle dynamics, component efficiencies, and the control strategy.

The National Renewable Energy Laboratory (NREL) has conducted a series of chassis dynamometer and road tests on the 2000 model-year Honda Insight. This paper will focus on results from the testing, how the results have been applied to NREL's Advanced Vehicle Simulator (ADVISOR), and how test results compare to the model predictions and published data. The chassis dynamometer testing included the FTP-75 emissions certification test procedure, highway fuel economy test, US06 aggressive driving cycle conducted at 0°C, 20°C, and 40°C, and the SC03 test performed at 35°C with the air conditioning on and with the air conditioning off. Data collection included bag and continuously sampled emissions (for the chassis tests), engine and vehicle operating parameters, battery cell temperatures and voltages, motor and auxiliary currents, and cabin temperatures.

The energy used to air condition an automobile has a significant effect on vehicle fuel economy and tailpipe emissions. If a small reduction in energy use can be applied to many vehicles, the impact on national fuel consumption could be significant. The SCO3 is a new emissions test conducted with the air conditioner (A/C) operating that is part of the Supplemental Federal Test Procedure (SFTP). With the 100% phase-in of the SFTP in 2004 for passenger cars and light light-duty trucks, there is additional motivation to reduce the size of the A/C system. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is investigating ways to reduce the amount of energy consumed for automobile climate control. If the peak soak temperature in an automobile can be reduced, the power consumed by the air conditioner may be decreased while passenger comfort is maintained or enhanced. Solar reflective glass is one way to reduce the peak soak temperature.

The impacts of fuel cell system power response capability on optimal hybrid and neat fuel cell vehicle configurations have been explored. Vehicle system optimization was performed with the goal of maximizing fuel economy over a drive cycle. Optimal hybrid vehicle design scenarios were derived for fuel cell systems with 10 to 90% power transient response times of 0, 2, 5, 10, 20, and 40 seconds. Optimal neat fuel cell vehicles where generated for responses times of 0, 2, 5, and 7 seconds. DIRECT, a derivative-free optimization algorithm, was used in conjunction with ADVISOR, a vehicle systems analysis tool, to systematically change both powertrain component sizes and the vehicle energy management strategy parameters to provide optimal vehicle system configurations for the range of response capabilities.

An ADVISOR model of a PNGV-class (80 mpg) vehicle with a fuel cell / battery hybrid electric drivetrain is developed using validated component models. The vehicle mass, electric traction drive, and total net power available from fuel cells plus batteries are held fixed. Results are presented for a range of fuel cell size from zero (pure battery EV) up to a pure fuel cell vehicle (no battery storage). The fuel economy results show that some degree of hybridization is beneficial, and that there is a complex interaction between the drive cycle dynamics, component efficiencies, and the control strategy.

The potential peaking of world conventional oil production and the possible imperative to reduce carbon emissions will put great pressure on vehicle manufacturers to produce more efficient vehicles, on vehicle buyers to seek them out in the marketplace, and on energy suppliers to develop new fuels and delivery systems. Four cases for stabilizing or reducing light vehicle fuel use, oil use, and/or carbon emissions over the next 50 years are presented. Case 1 - Improve mpg so that the fuel use in 2020 is stabilized for the next 30 years. Case 2 - Improve mpg so that by 2030 the fuel use is reduced to the 2000 level and is reduced further in subsequent years. Case 3 - Case 1 plus 50% ethanol use and 50% low-carbon fuel cell vehicles by 2050. Case 4 - Case 2 plus 50% ethanol use and 50% low-carbon fuel cell vehicles by 2050. The mpg targets for new cars and light trucks require that significant advances be made in developing cost-effective and very efficient vehicle technologies.

With the introduction of more fuel cell electric vehicles (FCEVs) on U.S. roadways, especially in California, the need for available hydrogen refueling stations is growing. While funding from the California Energy Commission is helping to solve this problem, solutions need to be developed and implemented to help reduce the time to commission a hydrogen station. The current practice of hydrogen station acceptance can take months because each vehicle manufacturer conducts their own testing and evaluation. This process is not practical or sufficient to support the timely development of a hydrogen fueling station network. To address this issue, as part of the Hydrogen Fueling Infrastructure Research and Station Technology (H2FIRST) Project Sandia National Laboratories and the National Renewable Energy Laboratory along with a team of stakeholders and contractor Powertech Labs has developed the Hydrogen Station Equipment Performance (HyStEP) Device.

An ultra-low sulfur diesel (ULSD) fuel was blended with three different biodiesel samples at 5 and 20 volume percent. The biodiesel fuels were derived from rapeseed and soybean oils, and in addition, a highly oxidized biodiesel was prepared from the soy biodiesel by oxidation under controlled conditions. A set of five elastomers commonly used in automotive fuel systems were examined before and after immersion in the six test blends and base fuel at 60°C for 1000 hours. The elastomers were evaluated for hardness, tensile strength, volume change and compression. Injector wear tests were also conducted on the base petrodiesel fuel and the biodiesel blends using a 500-hour test method developed for this study. Bosch VE (in-line) rotary pumps were evaluated for wear after testing for 500 hours on the base fuel, B5 and B20 test fuels. Additionally, a test procedure was developed to accelerate wear on common rail pumps over 500 hours.

One of the most critical elements in engineering a hydrogen fuel cell vehicle is the design of the on-board hydrogen storage system. Because the current compressed-gas hydrogen storage technology has several key challenges, including cost, volume and capacity, materials-based storage technologies are being evaluated as an alternative approach. These materials-based hydrogen storage technologies include metal hydrides, chemical hydrides, and adsorbent materials, all of which have drawbacks of their own. To optimize the engineering of storage systems based on these materials, it is critical to understand the impacts these systems will have on the overall vehicle system performance and what trade-offs between the hydrogen storage systems and the vehicle systems might exist that allow these alternative storage approaches to be viable.

Currently, several cost-per-mile calculators exist that can provide estimates of acquisition and operating costs for consumers and fleets. However, these calculators are limited in their ability to determine the difference in cost per mile for consumer versus fleet ownership, to calculate the costs beyond one ownership period, to show the sensitivity of the cost per mile to the annual vehicle miles traveled (VMT), and to estimate future increases in operating and ownership costs. Oftentimes, these tools apply a constant percentage increase over the time period of vehicle operation, or in some cases, no increase in direct costs at all over time. A more accurate cost-per-mile calculator has been developed that allows the user to analyze these costs for both consumers and fleets. Operating costs included in the calculation tool include fuel, maintenance, tires, and repairs; ownership costs include insurance, registration, taxes and fees, depreciation, financing, and tax credits.

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].

In this study, a 15-L heavy-duty diesel engine and an emission control system consisting of diesel oxidation catalysts, NOx adsorber catalysts, and diesel particle filters were evaluated over the course of a 2000 hour aging study. The work is a follow-on to a previously documented development effort to establish system regeneration and sulfur management strategies. The study is one of five projects being conducted as part of the U.S. Department of Energy's Advanced Petroleum Based Fuels - Diesel Emission Control (APBF-DEC) activity. The primary objective of the study was to determine if the significant NOx and PM reduction efficiency (>90%) demonstrated in the development work could be maintained over time with a 15-ppm sulfur diesel fuel. The study showed that high NOx reduction efficiency can be restored after 2000 hours of operation and 23 desulfation cycles.

Due to its high efficiency and superior durability the diesel engine is again becoming a prime candidate for future light-duty vehicle applications within the United States. While in Europe the overall diesel share exceeds 40%, the current diesel share in the U.S. is 1%. Despite the current situation and the very stringent Tier 2 emission standards, efforts are being made to introduce the diesel engine back into the U.S. market. In order to succeed, these vehicles have to comply with emissions standards over a 120,000 miles distance while maintaining their excellent fuel economy. The availability of technologies such as high-pressure common-rail fuel 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 the light-duty Tier 2 emission requirements. In support of this, the U.S.

In previous SAE papers, the initial development and testing of a vacuum-insulated catalytic converter was presented. This paper provides an update of the converter development and an analysis of potential off-cycle emissions savings. Hot vibration, cool-down, and 1975 Federal Test Procedure (FTP-75) emissions test results are provided to demonstrate the effectiveness of design improvements in greatly increasing durability while retaining performance. Using standard drive cycles and “real-world” driving statistics with a vehicle simulator (ADVISOR©), catalyst temperature and vehicle exhaust emissions of a sport utility vehicle (SUV) were predicted for 16 days of driving (107 trips, 770 total miles). Compared to the baseline vehicle with a conventional catalytic converter, the SUV with a vacuum-insulated converter produced 66% less non-methane hydrocarbon (NMHC), 65% less carbon monoxide (CO), and 60% less oxides of nitrogen (NOx).