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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.

In order to align with net-zero CO2 ambitions, automotive OEMs have been developing increasingly sophisticated strategies to minimise the impact that combustion engines have on the environment. Intelligent thermal management systems to actively control coolant flow around the engine have a positive impact on friction generated in the power cylinder by improving the warmup rate of cylinder liners and heads. This increase in temperature results in an improved frictional performance and cycle averaged fuel consumption, but also increases the piston to liner clearances due to rapid warm up of the upper part of the cylinder head. These increased clearances can introduce piston slap noise and substantially degrade the NVH quality to unacceptable levels, particularly during warmup after soak at low ambient temperatures. Using analytical techniques, it is possible to model the thermo-structural and NVH response of the power cylinder with different warm up strategies.

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.

The alternator provides power to vehicle electrical loads with the battery, and its maximum current depends on various factors such as electrical load, engine speed, thermal condition, and other variables. Above all, thermal effects make alternator simulations more complicated. For example statically similar conditions may show different results according to the temperature variation for each alternator operation. This paper proposes a two-stage statistically-based model structure which separates dynamic thermal effects from steady state performance. The method was validated by experiments and shows good predictive performance, suitable for use in test reduction.

In-cylinder flows such as tumble and swirl have an important role on the engine combustion efficiencies and emission formations. In particular, the tumble flow which is dominant in current high performance gasoline engines has an important effect on the fuel consumptions and exhaust emissions under part load conditions. Therefore, it is important to understand the effect of the tumble ratio on the part load performance and optimize the tumble ratio for better fuel economy and exhaust emissions. First step in optimizing a tumble flow is to measure a tumble ratio accurately. In this research the tumble ratio was measured, compared, and correlated using three different measurement methods: steady flow rig, 2-Dimensional PIV (Particle Image Velocimetry), and 3-Dimensional PTV (Particle Tracking Velocimetry). Engine dynamometer test was also conducted to find out the effect of the tumble ratio on the part load performance.

Despite the widespread adoption of lithium-ion batteries in various applications such as energy storage, concerns related to thermal management have been persisting, primarily due to the heat generated during their operation and the associated adverse effects on its efficiency, safety, and lifetime. Hence, the thermal characterization of lithium-ion batteries is essential for optimizing the layout of the battery cells for a pack design and the corresponding thermal management system. This study focuses on an experimental investigation of heat generation of Li-ion batteries under different operating conditions, including charge-discharge rates, ambient temperatures, states of charge, and compressive pressure. The experiments were conducted using a custom-designed multifunctional calorimeter, enabling precise measurement of the heat generation rate of the battery and the entropy coefficient. The measured results have shown a good match with the calculated heat generation rate.

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.

Radioactive tracer technology is an important tool for measuring component wear on a real-time basis and is especially useful in measuring engine wear as it is affected by combustion system operation and lubricant performance. Combustion system operation including the use of early and/or late fuel injection and EGR for emissions control can have a profound effect on aftertreatment contamination and engine reliability due to wear. Liner wear caused by localized fuel impingement can lead to excessive oil consumption and fuel dilution can cause excessive wear of rings and bearings. To facilitate typical wear measurement, the engine's compression rings and connecting rod bearings are initially exposed to thermal neutrons in a nuclear reactor to produce artificial radioisotopes that are separately characteristic of the ring and bearing wear surfaces.

Radioactive tracer technology (RAT) is an important tool in measuring component wear in an operating engine on a real-time basis. This paper will discuss the use of RAT to study and evaluate boundary lubricant and surfactant chemistries aimed at providing benefits in wear control. In particular, RAT was employed to study ring and bearing wear as a function of engine operating condition (speed, load, and temperature) and lubricant characteristics. Prior to testing, the engine's compression rings and connecting rod bearings were subjected to bulk thermal neutron bombardment in a nuclear reactor to produce artificial radioisotopes that were separately characteristic of the ring and bearing wear surfaces. The irradiated parts were installed in the test engine, after which testing to a specific test matrix was accomplished.

The market demands for CO2 reduction and fuel economy have led to a variety of new gear set concepts of automatic transmissions with 4 planetary gear sets and 6 shift elements in recent years. Understanding the relationship between the torque of clutch and brake and gear ratio in the design stage is very important to assess new gear set concepts and to set up the control strategy for enhancing shift quality and to reduce the heat generation of clutch and brake. In this paper, a new systematic approach is used to unify the relationship between torque and gear ratio during the gear shift for all multi-step planetary automatic transmissions. This study describes the unified concept model with a lumped inertia regardless of the specific transmission layout and derives the principal unified relationship equations using torque and energy analysis, which prove that the sum of brake torque is always gear ratio -1 in every in-gear.

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.

Various deformation shapes of the vehicle body were investigated for the purpose to establish vehicle body's performance criteria which correlates well to handling performance and ride comfort. Using CAE tool, the dynamic behavior of a structure by its modal parameter can be described instead of by its nodes and elements. Each modal characteristic in a dynamic system is reduced by its modal stiffness, its modal mass and its damping parameter in the model. This technology offers not only computational efficiency but also parametric model enabling easy what-if simulation. This reduced model can be obtained by modal test as well as simulation of full FE model. It was also investigated that which mode is sensitive to ride or handling performance using the parameterized model. The body stiffness of the brand new 2010 SONATA was improved on reference to the sensitivity analysis. The ride and handling performance of the 2010 SONATA were verified by computer simulation and vehicle field test

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.

Dedicated EGR has shown promise for achieving high efficiency with low emissions [1]. For the present study, a 4-cylinder turbocharged GDI engine which was modified to a D-EGR configuration was used to investigate the impact of valve phasing and different injection strategies on the reformate production in the dedicated cylinder. Various levels of positive valve overlap were used in conjunction with different approaches for dedicated cylinder over fueling using PFI and DI fuel systems. Three speed-load combinations were studied, 2000 rpm 4 bar IMEPg, 2000 rpm 12 bar IMEPg, and 4000 rpm 12 bar IMEPg. The primary investigation was conducted to map out the dedicated cylinders' performance at the operating limits of intake and exhaust cam phasing. In this case, the limits were defined as conditions that yielded either no reformate benefit or led to instability in the dedicated cylinder.

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.

With the advent of cars with computerized engines, drivers sometimes suffer discomfort with “check engine” light problem, and as a result, insist on increasing levels of reliability in their cars. Hence, reliability of the wiring harness has become a very important automotive design characteristic. On one hand, the more secure an engine mounting system is, the more stable the engine wiring harness is. In order to enhance their durability, car manufacturers need to perform many validation tests during the development phase which involves a lot of time and cost. In this study, a newly developed lab-simulation test is proposed to qualify the design of engine mounting and engine wiring early in the design cycle and reduce time and expense. The lab-simulation test has contributed to a significant cost and time reduction and has shown good correlation to the original proving ground test.

Transmission error has been well known as the main source of excitation about transmission gear whine noise. To minimize transmission error in the gear system, various analysis methods have been studied and applied for long time. Many researchers were focused on gear micro geometry to achieve the low level of transmission error. But, if the gear is misaligned by several factors such as clearance and manufacturing tolerance error, then the gear noise can rapidly and unexpectedly be increased. To overcome this problem, this new analysis method has been developed and introduced. A transmission system simulation model was constructed, which considers various factors of transmission components such as clearance, stiffness and so on. The deformation and vibration characteristics of finite element models were validated by making comparison with frequency response function experiment.