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Industries related to automotive manufacturing and its supply chain play a key role in leaving a carbon footprint during an automobile's life cycle. Per the report from Lawrence Berkeley National Laboratory (LBNL) in March, 2008 [1], “motor vehicle industry in the U.S. spends about $3.6 billion on energy annually.” The proposed research will focus on energy savings opportunities in automotive manufacturing and its supplier network. The US Department of Energy (DOE) funds 24 Industrial Assessment Centers (IAC) throughout the U.S. that conduct energy assessments at many of these facilities. The results of these assessments are summarized in a database maintained by Rutgers University which acts as the central management body for all the IACs. This research will present key concepts summarized from this database.

Emissions from light duty vehicles have traditionally been measured using a chassis dynamometer, while heavy duty testing has been based on engine dynamometers. However, the need for in-use vehicle emissions data has led to the development of two transportable heavy duty chassis dynamometers capable of testing buses and heavy trucks. A test cycle has been developed for Class 8 trucks, which typically have unsyncronized transmissions. This test cycle has five peaks, each consisting of an acceleration, cruise period, and deceleration, with speeds and acceleration requirements that can be met by virtually all vehicles in common service. Termed the “WVU 5 peak truck test”, this 8 km (5 mile) cycle has been used to evaluate the emissions from diesel and ethanol powered over-the-road tractors and from diesel and ethanol powered snow plows, all with Detroit Diesel 6V92 engines.

The use of a soy-based diesel fuel (biodiesel) has potential advantages over the use of a conventional petroleum diesel fuel including: Reduced dependence on foreign petroleum Lowering of greenhouse gas emissions Less air pollution and related public health risks in urban areas A life cycle study performed by the U.S. Department of Energy's National Renewable Energy Laboratory, the U.S. Department of Agriculture's Office of Energy and Ecobalance (completed in May 1998) helped to quantify the environmental benefits of the “cradle-to-grave” production and use of biodiesel. The study showed, for example, that substituting 100% biodiesel for petroleum diesel in urban buses reduced the life cycle emissions of carbon dioxide (CO2) by 78%. The study also pointed out some trade-offs of using biodiesel including increased life cycle hydrocarbon and NOx emissions.

A bi-fuel engine capable of operating either on compressed natural gas (CNG) or gasoline is being developed for the transition to alternative fuel usage. A Saturn 1.9 liter 4-cylinder engine was selected as a base powerplant. A control system that allows closed-loop optimization of both fuel delivery and spark timing was developed. Stock performance and emissions of the engine, as well as performance and emissions with the new controller on gasoline and CNG, have been documented. CNG operation in an engine designed for gasoline results in power loss because of the lower volumetric efficiency with gaseous fuel use, yet such an engine does not take advantage of the higher knock resistance of CNG. It is the goal of this research to use the knock resistance of CNG to recover the associated power loss. The two methods considered for this include turbocharging with a variable boost wastegate and raising the compression ratio while employing variable valve timing.

A heavy-duty engine testing project involving Cummins Engine Company, Southwest Research Institute (SwRI), and West Virginia University (WVU) has been completed. This project evaluated the transient exhaust gas emissions rate of Cummins N-14 heavy-duty diesel engines converted to natural gas. Three heavy-duty N-14 diesel engines were converted to run on natural gas using a lean burn strategy by SwRI and are in field service in Santa Barbara Air Pollution Control District (SBAPCD). Two of the engines were tested under a steady-state cycle that simulates the U.S. heavy-duty transient cycle. The third engine was tested at the WVU Engine Research Laboratory following the U.S. Federal Test Procedure (FTP). However, at WVU, lean burn combustion strategy was shifted rich of stoichiometric during idling time of the FTP test. This may have caused the engine to produce more total hydrocarbons (THC) and carbon monoxide (CO).

The paper captures the recent events in relation with the Volkswagen (VW) Emissions Scandal and addresses the impact of this event on the future of power train development. The paper analyses the impact on the perspectives of the internal combustion engine, the battery based electric car and the hydrogen based technology. The operation of the United States Environmental Protection Agency (EPA), VW and the United States prosecutor, sparked by the action of the International Council on Clean Transportation (ICCT) is forcing the Original Equipment Manufacturers (OEM) towards everything but rationale immediate transition to the battery based electric mobility. This transition voids the value of any improvement of the internal combustion engine (ICE), especially in the lean burn, compression ignition (CI) technology, and of a better hybridization of powertrains, both options that have much better short term perspectives than the battery based electric car.

Regulated emissions (THC, CO, NOx, and PM) and particulate SOF and sulfate fractions were determined for a 1995 Detroit Diesel Series 50 urban bus engine at varying fuel sulfur levels, with and without catalytic converters. When tested on EPA certification fuel without an oxidation catalyst this engine does not appear to meet the 1994 emissions standards for heavy duty trucks, when operating at high altitude. An ultra-low (5 ppm) sulfur diesel base stock with 23% aromatics and 42.4 cetane number was used to examine the effect of fuel sulfur. Sulfur was adjusted above the 5 ppm level to 50, 100, 200, 315 and 500 ppm using tert-butyl disulfide. Current EPA regulations limit the sulfur content to 500 ppm for on highway fuel. A low Pt diesel oxidation catalyst (DOC) was tested with all fuels and a high Pt diesel oxidation catalyst was tested with the 5 and 50 ppm sulfur fuels.

Heavy-duty diesel engines (HDDE), because of their widespread use and reputation of expelling excessive soot, have frequently been held responsible for excessive amounts of overall environmental particulate matter (PM). PM is a considerable contributor to air pollution, and a subject of primary concern to health and regulatory agencies worldwide. The U.S. Environmental Protection Agency (EPA) has provided PM emissions regulations and standards of measurement techniques since the 1980's. PM standards set forth by the EPA for HDDEs are based only on total mass, instead of size and/or concentration. The European Union adopted a particle number emission limit, and it may influence the U.S. EPA to adopt particle number or size limits in the future. The purpose of this research was to study the effects biodiesel blended fuel and cetane improvers have on particle size and number.

An alternative fuel that has demonstrated considerable potential in reducing emissions and crude oil dependence is compressed natural gas (CNG). A dedicated CNG vehicle suffers from the lack of an adequate number of fueling stations and the poor range limited by CNG storage technology. A vehicle capable of operating on either gasoline or natural gas allows alternative fuel usage without sacrificing vehicle range and mobility. Although many such bi-fuel vehicles are in existence, historically they have employed older engine designs and made compromises in engine control parameters that can degrade performance relative to gasoline and increase emissions. A modern production engine, a 1992 Saturn 1.9 liter 16 valve powerplant, is being optimized for operation on each fuel to realize the full potential of CNG in a bi-fuel system. CNG operation in an engine designed for gasoline typically suffers from reduced power, due in part to displacement of air by gaseous fuel.

Growing concern over ground-level ozone and its role in smog formation has resulted in extensive investigation into identifying ozone sources. Motor vehicle exhaust, specifically oxides of nitrogen and hydrocarbons, have been identified as major ozone precursors in urban areas. Past research has concentrated on assessing the impact of emissions from gasoline fueled light duty vehicles. However, little work has been done on identifying ozone precursors from medium and heavy duty diesel fueled vehicles. This paper presents the results of testing performed on a Navistar T 444E 190 horsepower diesel engine which is certified as a light/heavy-duty emissions classification and is used in medium duty trucks up to 11,800 kg (26,000 lb) GVW. Regulated emissions and speciated hydrocarbon emissions were collected using a filter, bag and Tenax adsorption cartridges for both steady state and transient engine operation.

An electrochemical cell is presented which reduces NOx emissions from a vehicle fueled by dedicated natural gas. The cell is comprised of a honeycomb shaped ceramic which is chemically coated with an electrically conductive material in two distinct regions which serve as electrodes such that, with the application of a voltage potential, a cathode and anode are formed. As the exhaust gas flows through the inner channels of the cell, the electrochemical reduction of NOx at the cathode yields nitrogen gas and oxide ions. The nitrogen continues to flow through the cell while the oxide ions dissolve in the solid electrolyte. At the anodic zone, oxide ions are converted to oxygen gas. The pressure drop across the cell was experimentally measured to insure that the back pressure created by the cell does not create a significant reduction in the efficiency of the engine.

Techniques have been developed to sample and speciate dilute heavy duty diesel exhaust to determine the specific reactivities and the ozone forming potential. While the Auto/Oil Air Quality Improvement Research Program (AQIRP) has conducted a comprehensive investigation to develop data on potential improvements in vehicle emissions and air quality from reformulated gasoline and various other alternative fuels. However, the development of sampling protocols and speciation of heavy duty diesel exhaust is still in its infancy [1, 2, 3, 4, 5 and 6]. This paper focuses on the first phase of the heavy duty diesel speciation program, that involves the development of a unique set of sampling protocols for the gas phase, semi-volatile and particulate matter from the exhaust of engines operating on different types of diesel fuel. Effects of sampling trains, sampling temperatures, semi-volatile adsorbents and driving cycles are being investigated.

The influences of laboratory-induced hydrogen on the tensile deformation and fracture behavior of selected sheet steels including conventional DQSK and HSLA steels as well as newer DP and TRIP grades were evaluated. The effects of cold work, simulated paint baking, and natural aging were considered. Hydrogen effects were observable by increased flow stress, decreased ductility, altered neck geometry, and altered fracture mechanisms. Differences among the steels and conditions were observed and interpreted on the basis of microstructure, fracture behavior, and theories of hydrogen embrittlement.

Relationships between diesel particulate matter (PM) mass and gaseous emissions mass produced by engines have been explored to determine whether any gaseous species may be used as surrogates to infer PM quantitatively. It was recognized that sulfur content of fuel might independently influence PM mass, since PM historically is composed of elemental carbon, organic carbon, sulfuric acid, ash and wear particles. Previous research has suggested that PM may be correlated with carbon monoxide (CO) for an engine that is exercised through a variety of speed and load cycles, but that the correlation does not extend to a group of engines. Large databases from the E-55/59 and Gasoline/Diesel PM Split programs were employed, along with the IBIS bus emissions database and several additional data sets for on- and off-road engines to examine possible relationships.

Methane emissions from lean-burn natural gas engines can be relatively high. As natural gas fueled vehicles become more prevalent, future regulations may restrict these emissions. Preliminary reports indicated that conventional, precious metal oxidation catalysts rapidly deactivate (in less than 50 hours) in lean-burn natural gas engine exhaust. This investigation is directed at quantifying this catalyst deactivation and understanding its cause. The results may also be relevant to oxidation of lean-burn propane and gasoline engine exhaust. A platinum/palladium on alumina catalyst and a palladium on alumina catalyst were aged in the exhaust of a lean-burn natural gas engine (Cummins B5.9G). The engine was fueled with compressed natural gas. Catalyst aging was accomplished through a series of steady state cycles and heavy-duty transient tests (CFR 40 Part 86 Subpart N) lasting 10 hours. Hydrocarbons in the exhaust were speciated by gas chromatography.

Racing continues to be the singular, preeminent source of powertrain development for automakers worldwide. Engineering teams rely on motorsports for the latest prototype testing and research. Endurance racing provides the harshest and most illuminating stage for system design validation of any motorsport competition. While advancements throughout the 20th Century brought about dramatic increases in engine power output, the latest developments from endurance racing may be more impactful for fuel efficiency improvements. Hybrid powertrains are a critical area of research for automakers and are being tested on the toughest of scales. Prototype Powertrain in Motorsport Endurance Racing brings together ten vital SAE technical papers and SAE Automotive Engineering magazine articles surrounding the advancements of hybrid powertrains in motorsports.

Concern over dwindling oil supplies has led to the adoption of alternate fuels to power fleet vehicles. However, during the interim period when alternate fuel supply stations are few and far between, dual fuel engines prove a necessity. In the light duty arena, these engines are typically gasoline engines modified to accommodate compressed natural gas (CNG) as an alternate fuel, but they are seldom optimized with both fuels in mind. A Saturn 1.9 liter 4 cylinder dual overhead cam engine was selected as a base for developing an optimized gasoline/CNG powerplant. Baseline data on power and steady state emissions (CO2, CO, NOx, HC) were found using the standard Saturn controller. In addition to monitoring standard sensor measurements, real-time pressure traces were taken for up to 256 cycles using a modified head with embedded PCB piezoelectric pressure transducers.

Natural Gas engines are viewed as an alternative to diesel power in the quest to reduce heavy duty vehicle emissions in polluted urban areas. In particular, it is acknowledged that natural gas has the potential to reduce the inventory of particulate matter, and this has encouraged the use of natural gas engines in transit bus applications. Extensive data on natural gas and diesel bus emissions have been gathered using two Transportable Heavy Duty Vehicle Emissions Testing Laboratories, that employ chassis dynamometers to simulate bus inertia and road load. Most of the natural gas buses tested prior to 1997 were powered by Cummins L-10 engines, which were lean-burn and employed a mechanical mixer for fuel introduction. The Central Business District (CBD) cycle was used as the test schedule.

Further growth of diesel engines in the light-duty and heavy-duty vehicular market is closely linked to the potential health risks of diesel exhaust. The California Air Resources Board and the Office of Environmental Health Hazard Assessment have identified diesel exhaust as a toxic air contaminant. The International Agency for Research on Cancer concluded that diesel particulate is a probable human carcinogen [1]. Cleaner burning liquid fuels, such as those derived from natural gas via the Fischer-Tropsch (FT) process, offer a potentially economically viable alternative to standard diesel fuel while providing reduced particulate emissions. Further understanding of FT operation may be realized by investigating the differences in toxicity and potential health effects between particulate matter(PM) derived from FT fuel and that derived from standard Federal diesel No. 2 (DF).

The goal of this project is the development and characterization of synthetic membranes for the separation and purification of CO2 from the Martian atmosphere for in-situ resource utilization (ISRU) applications such as in-situ propellant production. Candidate materials should have high selectivity for carbon dioxide over nitrogen and argon, and a glass transition temperature of -40 °C or less to remain in rubbery state at low temperature for high permeance (flux/driving force). Membrane materials we identified include the rubbery polymers poly(dimethyl siloxane) (PDMS) and the copolymer poly(dimethyl, methylphenyl siloxane) (PMPS). Pure and mixed gas permeation experiments with CO2, N2 and Ar were performed with these membrane materials in the temperature range -25 to 21 °C. In experiments with the commercially available PDMS membranes, the pure gas CO2 permeability increases from 1932 Barrers to 2755 Barrers as the temperature decreases from 22 to -30 °C.