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Dedicated Exhaust Gas Recirculation (D-EGR®) technology provides a novel means for fuel efficiency improvement through efficient, on-board generation of H2 and CO reformate [1, 2]. In the simplest form of the D-EGR configuration, reformate is produced in-cylinder through rich combustion of the gasoline-air charge mixture. It is also possible to produce more H2 by means of a Water Gas Shift (WGS) catalyst, thereby resulting in further combustion improvements and overall fuel consumption reduction. In industrial applications, the WGS reaction has been used successfully for many years. Previous engine applications of this technology, however, have only proven successful to a limited degree. The motivation for this work was to develop and optimize a WGS catalyst which can be employed to a D-EGR configuration of an internal combustion engine. This study consists of two parts.

Results from work focusing on the development of an ultra low emissions, high efficiency, natural gas-fueled heavy- duty engine are discussed in this paper. The engine under development was based on a John Deere 8.1L engine; this engine was significantly modified from its production configuration during the course of an engine optimization program funded by the National Renewable Energy Laboratory. Previous steady-state testing indicated that the modified engine would provide simultaneous reductions in nonmethane hydrocarbon emissions and fuel consumption while maintaining equivalent or lower NOx levels. Federal Test Procedure transient tests confirmed these expectations. Very low NOx emissions, averaging 1.0 g/bhp-hr over hot-start cycles, were attained; at these conditions, reductions in engine-out nonmethane hydro-carbons emissions (NMHC) were approximately 30 percent, and fuel consumption over the cycle was also reduced relative to the baseline.

A project was conducted by Southwest Research Institute on behalf of the California Air Resources Board and the South Coast Air Quality Management District to demonstrate the technical feasibility of utilizing closed-loop three-way catalyst technology in off-road equipment applications. Five representative engines were selected, and baseline emission-tested using both gasoline and LPG. Emission reduction systems, employing three-way catalyst technology with electronic fuel control, were designed and installed on two of the engines. The engines were then installed in a fork lift and a pump system, and limited durability testing was performed. Results showed that low emission levels, easily meeting CARB's newly adopted large spark-ignited engine emission standards, could be achieved.

A new approach to reclaiming the spoil areas produced by area-type mining operations has been developed. This system uses a machine known as a winch-dozer, consisting of a pair of large back-to-back buckets which are drawn by cable across spoil piles, moving back and forth between a “tailblock” anchor and a “drawworks” winch unit developed as an attachment to a large crawler tractor. The system is expected to reduce the cost of reclamation leveling by 40-50%. The system permits more effective power utilization due to the blade system's light weight, induces caving of spoil banks, and permits moving spoil in both directions of blade travel.

The Texas Department of Transportation (TxDOT) began using an ultra-low-sulfur, low aromatic, high cetane number diesel fuel (TxLED, Texas Low Emission Diesel) in June 2003. They initiated a simultaneous study of the effectiveness to reduce emissions and influence fuel economy of this fuel in comparison to 2D on-road diesel fuel used in both their on-road and off-road equipment. The study incorporated analyses for the fleet operated by the Association of General Contractors (AGC) in the Houston area. Some members of AGC use 2D off-road diesel in their equipment. One off-road engine, two single-axle dump trucks, and two tandem-axle dump trucks were tested. The equipment tested included newer electronically-controlled diesels. The off-road engine was tested over the TxDOT Telescoping Boom Excavator Cycle. The dump trucks were tested using the “route” technique over the TxDOT Single-Axle Dump Truck Cycle or the TxDOT Tandem-Axle Dump Truck Cycle.

The Texas Department of Transportation began using an emulsified diesel fuel in 2002. They initiated a simultaneous study of the effectiveness of this fuel in comparison to 2D on-road diesel fuel and 2D off-road diesel. The study included comparisons of fuel economy and emissions for the emulsion, Lubrizol PuriNOx®, relative to conventional diesel fuels. Two engines and eight trucks, four single-axle dump trucks, and four tandem-axle dump trucks were tested. The equipment tested included both older mechanically-controlled diesels and newer electronically-controlled diesels. The two engines were tested over two different cycles that were developed specifically for this project. The dump trucks were tested using the “route” technique over one or the other of two chassis dynamometer cycles that were developed for this project In addition to fuel efficiency, emissions of NOx, PM, CO, and HCs were measured. Additionally, second-by-second results were obtained for NOx and HCs.

The Texas Department of Transportation (TxDOT) began using an emulsified diesel fuel in July 2002. They initiated a simultaneous study of the effectiveness of this fuel in comparison to 2D on-road diesel fuel, which they use in both their on-road and off-road equipment. The study also incorporated analyses for the fleet operated by the Associated General Contractors (AGC) in the Houston area. Some members of AGC use 2D off-road diesel fuel in their equipment. The study included comparisons of fuel economy and emissions for the emulsified fuel relative to the conventional diesel fuels. Cycles that are known to be representative of the typical operations for TxDOT and AGC equipment were required for use in this study. Four test cycles were developed from data logged on equipment during normal service: 1) the TxDOT Telescoping Boom Excavator Cycle, 2) the AGC Wheeled Loader Cycle, 3) the TxDOT Single-Axle Dump Truck Cycle, and 4) the TxDOT Tandem-Axle Dump Truck Cycle.

The new Beijing Automotive Industry Corporation (BAIC) engine, an evolution of the 2.3L 4-cylinder turbocharged gasoline engine from Saab, was designed, built, and tested with close collaboration between BAIC Motor Powertrain Co., Ltd. and Southwest Research Institute (SwRI®). The upgraded engine was intended to achieve low fuel consumption and a good balance of high performance and compliance with Euro 6 emissions regulations. Low fuel consumption was achieved primarily through utilizing cooled low pressure loop exhaust gas recirculation (LPL-EGR) and dual independent cam phasers. Cooled LPL-EGR helped suppress engine knock and consequently allowed for increased compression ratio and improved thermal efficiency of the new engine. Dual independent cam phasers reduced engine pumping losses and helped increase low-speed torque. Additionally, the intake and exhaust systems were improved along with optimization of the combustion chamber design.

Diesel Cylinder Deactivation (CDA) has been shown in previous work to increase exhaust temperatures, improve fuel efficiency, and reduce engine-out NOx for engine loads up to 3 bar BMEP. The purpose of this study is to determine whether or not the turbocharger needs to be altered when implementing CDA on a diesel engine. This study investigates the effect of CDA on exhaust temperature, fuel efficiency, and turbocharger performance in a 15L heavy-duty diesel engine under low-load (0-3 bar BMEP) steady-state operating conditions. Two calibration strategies were evaluated. First, a “stay-hot” thermal management strategy in which CDA was used to increase exhaust temperature and reduce fuel consumption. Next, a “get-hot” strategy where CDA and elevated idle speed was used to increase exhaust temperature and exhaust enthalpy for rapid aftertreatment warm-up.

The use of biodiesel fuels derived from vegetable oils or animal fats as a substitute for conventional petroleum fuel in diesel engines has received increased attention. This interest is based on a number of properties of biodiesel including the fact that it is produced from a renewable resource, its biodegradability, and its potential beneficial effects on exhaust emissions. Transient exhaust emissions from three modern diesel engines were measured during this study, both with and without an oxidation catalyst. Emissions were characterized with neat biodiesel and with a blend of biodiesel and conventional diesel fuel. Regulated emissions and performance data are presented in this paper, while the results of a detailed chemical characterization of exhaust emissions are presented in a companion paper. The use of biodiesel resulted in lower emissions of unburned hydrocarbons, carbon monoxide, and particulate matter, with some increase in emissions of oxides of nitrogen on some engines.

The major events in the development of a “pumpless” gas engine concept are related. The immediate objective of the subject program was to develop a combustion system for natural gas fueled engines which, when compared with conventional gas engines, would be operationally simpler and easier to maintain with no appreciable penalty in specific fuel consumption. The pumpless gas principle was successfully demonstrated on a single-cylinder, 2-cycle engine. The concept was then extended, with the aid of combustion photography, to a single-cylinder, 4-cycle laboratory engine. The feasibility of the concept was further demonstrated by the conversion of a commercially available 4-cycle, 4-cyl diesel engine.

Over twenty prototype hybrid buses and other commercial vehicles are currently being completed and deployed. These vehicles are primarily “series” hybrid vehicles which use electric motors for primary traction while internal combustion engines, or high-speed turbine engines connected to generators, supply some portion of the electric propulsion and battery recharge energy. Hybrid-electric vehicles have an electric energy storage system on board that influences the operation of the heat engine. The storage system design and level affect the vehicle emissions, electricity consumption, and fuel economy. Existing heavy-duty emissions test procedures require that the engine be tested over a transient cycle before it can be used in vehicles (over 26,000 lbs GVW). This paper describes current test procedures for assessing engine and vehicle emissions, and proposes techniques for evaluating engines used with hybrid-electric vehicle propulsion systems.

A technology demonstration program was conducted by the U.S. Army to verify the feasibility of using aviation turbine fuel JP-8 in all military diesel fuel-consuming ground vehicles and equipment (V/E). Over 2,800 pieces of military equipment participated in a two and one-half year program accumulating over 2,621,000 total miles (4,219,810 km) using JP-8 in combat/tracked, tactical/wheeled, and transportation motor pool vehicles. Over 71,000 hours of operation were accumulated in diesel/turbine engine-driven generator sets using JP-8 fuel. Comparisons of various performance areas with baseline diesel fuel (DF-2) operation were made.

A gasoline direct injection engine was operated at elevated EGR levels over a significant portion of the performance map. The engine was modified to use both cooled and un-cooled EGR in high pressure loop and low pressure loop configurations. The addition of EGR at low and part load was shown to decrease NO and CO emissions and to reduce fuel consumption by up to 4%, primarily through the reduction in pumping losses. At high loads, the addition of EGR resulted in higher fuel consumption benefits of 10-20% as well as the expected NO and CO reductions. The fuel economy benefit at high loads resulted from a decrease in knock tendency and a subsequent improvement in combustion phasing as well as reductions in exhaust temperatures that eliminated the requirement for over-fuelling.

This paper discusses the techniques and diagnostic significance of atomic absorption, atomic emission, and infrared spectrometric analysis of crankcase lubricants, with the use of supplementary data where pertinent. The parameters affecting used oil analytical data are discussed in terms of examples from Army general purpose vehicle test engines. Wear metals in used gear oils are also discussed and examples are given. Analytical methods and their applications are fully described, and the equipment and procedures for infrared spectroscopy and gas chromatography techniques are outlined.

Five light-duty vehicles were used to investigate HC, CO, and NOx emissions and fuel economy sensitivity to changes in the length of soak period preceding the EPA Urban Dynamometer Driving Schedule (UDDS). Emission tests were conducted following soak periods 10 minutes to 36 hours in length. Each of the first 8 minutes of the driving cycle was studied separately to observe vehicle warm-up. Several engine and fuel system temperatures were monitored during soak and run periods and example trends are illustrated. The extent to which emission rates and fuel consumption are affected by soak period length is discussed.

The optical spark plug probe and ionization head gasket probe developed at Sandia Laboratories were applied to one cylinder of a production multicylinder automotive gasoline engine. The purpose of this application is to eventually study combustion phenomena leading to high emissions under cold start and cold idle conditions. As a first step in studying cold start combustion and emissions issues, diagnostic instrumentation was simultaneously applied to a production engine under steady state idle, road load and an intermediate load-speed condition. The preliminary application of such instrumentation is the subject of the present paper. The spark plug probe was redesigned for ease of use in production engines and to provide a more robust design. The two probes were geometrically oriented to obtain radial line-up between the optical windows and ionization probes. Data were taken simultaneously with both probes at the three load-speed conditions mentioned above.

The Scuderi engine is a split cycle design that divides the four strokes of a conventional combustion cycle over two paired cylinders, one intake/compression cylinder and one power/exhaust cylinder, connected by a crossover port. This configuration provides potential benefits to the combustion process, as well as presenting some challenges; it also creates the possibility for pneumatic hybridization of the engine. This paper presents the methodology and results of a comprehensive study to investigate the benefits of air hybrid operation with the Scuderi Split Cycle (SSC) engine. Four air hybrid operating modes are made possible by the Split Cycle configuration, namely air compressor, air expander, air expander & firing and firing & charging. The predicted operating requirements for each individual operating mode are established. The air and fuel flow of the individual modes are fully mapped throughout the engine operating speed and load range and air tank pressure operating range.

The U.S. Army's National Automotive Center has contracted with Illinois Institute of Technology Research Institute (IITRI), Southwest Research Institute (SwRI), and Advanced Propulsion, LLC, to evaluate the effects on fuel consumption and logistics that would result from hybridizing the powertrains of the Army's tactical wheeled vehicle fleet. This paper will outline the approach taken to perform that evaluation and present a synopsis of results achieved to date.

The process of developing, parameterizing, validating, and maintaining models occurs within a wide variety of tools, and requires significant time and resources. To maximize model utilization, models are often shared between various toolsets and experts. One common example is sharing aircraft engine models with airframers. The functionality of a given model may be utilized and shared with a secondary model, or multiple models may run collaboratively through co-simulation. There are many technical challenges associated with model sharing and co-simulation. For example, data communication between models and tools must be accurate and reliable, and the model usage must be well-documented and perspicuous for a user. This requires clear communication and understanding between computer scientists and engineers. Most often, models are developed by engineers, whereas the tools used to share the models are developed by computer scientists.