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Mechanisms of NH₃ generation using LNT-like catalysts have been studied in a bench reactor over a wide range of temperatures, flow rates, reformer catalyst types and synthetic exhaust-gas compositions. The experiments showed that the on board production of sufficient quantities of ammonia on board for SCR operation appeared feasible, and the results identified the range of conditions for the efficient generation of ammonia. In addition, the effects of reformer catalysts using the water-gas-shift reaction as an in-situ source of the required hydrogen for the reactions are also illustrated. Computations of the NH₃ and NOx kinetics have also been carried out and are presented. Design and impregnation of the SCR catalyst in proximity to the ammonia source is the next logical step. A heated synthetic-exhaust gas flow bench was used for the experiments under carefully controlled simulated exhaust compositions.

To manage the function of a vehicle's engine, transmission, and related subsystems, almost all modern vehicles make use of one or more electronic controllers running embedded software, henceforth referred to as a Powertrain Controller System or PCS. Fully validating this PCS is a necessary step of vehicle development, and the validation process requires extensive amounts of testing. Within the automotive industry, more and more of this validation testing is being performed using Hardware-in-the-Loop (HIL) simulators to automate the extensive test sequences. A HIL simulation typically mates the physical PCS to a closed-loop real time computer simulation of a powertrain. Interfacing the physical PCS hardware to a powertrain simulation requires the HIL simulator to have extensive signal input/output (I/O) electronics and simulated actuator electrical loading.

This paper presents a numerical model of the rotational and lateral dynamics of the piston (secondary motion) and piston slap in mixed lubrication. Piston dynamic behavior, frictional and impact forces are predicted as functions of crank angle. The model considers piston skirt surface waviness, roughness, skirt profile, thermal and mechanical deformations. The model considers partially-flooded skirt and calculates the pressure distributions and friction in the piston skirt region for both hydrodynamic and boundary lubrication. Model predictions are compared with measurements of piston position using gap sensors in a single-cylinder engine and the comparison between theory and measurement shows remarkable agreement.

Cranking and startup fuel control has become increasingly important due to ever tightening emission requirements. Additionally, engine-off strategies during idle will require substantially more engine startup events with the associated need for very clean starts. Thus, knowledge of an engine's Air-Fuel Ratio (AFR) during its early cycles is necessary in order to optimize cranking and startup fueling. This paper examines and compares two methods of measuring an engine's AFR during engine startup (approximately the first second of operation); an in-cylinder technique using a Fast Flame Ionization Detector (FFID) and the conventional exhaust based Universal Exhaust Gas Oxygen (UEGO) sensor method. Engine starts using a Ford Zetec engine were performed at three different temperatures (0, 20 and 90 C) as well as different initial engine starting positions.

Three fuels with cetane numbers of 45, 36 and 29 have been run at four load levels at each of three speeds in a Detroit: Diesel 3–71 engine with standard injectors. Measurements of temperatures, pressures, Load, fuel flow, cylinder pressure in one cylinder, strain gauge measurements from the rocker arm operating one injector and exhaust emissions were all recorded. Comparisons show little change in operation except for increases in ignition delay and rate of cylinder pressure rise with the low cetane fuels. It was concluded, on the basis of these short runs, that the intermediate fuel probably would not cause major difficulties but the lowest cetane fuel could possibly present problems with noise and engine durability.

The present day measure of the ignition quality of a diesel fuel is the cetane number. Cetane number determination is carried out using a special single cylinder engine with reproducible operating conditions and variable compression ratio. The importance of the carbon skeletal structure of the fuel on the ignition quality is qualitatively well known, but the practice of defining the ignition quality of diesel fuels by a term, whose physical and/or chemical meaning is not well understood, has not been abandoned yet. The correlations that have been proposed recently, which relate the total fuel aromaticity or mid-boiling point, hydrogen content and density to the cetane number, suffer from the lack of representation of the fuel's compositional structure, and of well defined relationship, if any, between boiling point, hydrogen content, density and ignition quality.

Six experimental fuels representative of Canadian future fuel options were tested against a reference fuel in a Bombardier 12 cylinder, 4 stroke, 3000 hp, medium speed diesel. The reference fuel was a straight run ASTM #2-D. The first test fuel blend consisted of heavy atmospheric gas oil that extended the distillation range (higher end point) of the other blend component ASTM #2-D. The second fuel was a blend of a distillate cut from a mixture of conventional and tar sands crude with hydrogen treated cracked stock. This provided a fuel with substantial levels of aromatic and cracked components. The third fuel was gas oil side stream: a low cetane number, high aromatics level tar sands distillate. The fourth fuel was an equal portion blend of tar sands crude components, gas oil side-stream and heavy unifined gas oil. The fifth fuel was a blend of ASTM #2-D heating oil and a substantial portion of stabilized cracked stock.

A critical evaluation of the current ASTM method of rating diesel fuels, and of the available non-engine techniques for the estimation of cetane nunbers of diesel fuels is presented. The relationship between ignition quality and fuel composition is reviewed and it is shown that each member of an homologous series of hydrocarbons does not have the same ignition characteristics as the other members of the series. It is emphasized that the belief that paraffins have relatively high cetane ratings as compared to aromatics and cycloparaffins is not always correct. The basic flaw in the cetane index correlations, which use the easily measurable physical properties of the fuels as independent parameters, is explained. A fuel data base has been used to compare the different correlations.

Four experimental diesel fuels with cetane numbers (CN) of 40, 37, 35 and 27 have been tested in a Detroit Diesel Allison 3-71 engine using the standard N65 injectors. The 35 CN fuel was a blend of distillates from conventional and tar sands crude with hydrogen treated cat-cracked stock. This provided a fuel typical of the 1990's and beyond, with substantial levels of aromatic and cracked components. The 27 CN fuel was a blend of the same components as the 35 CN fuel only with a larger portion of the hydrogen treated cat-cracked component. The 40 CN fuel was identical to the 35 CN fuel with a .2% DII-3 Diesel Ignition Improver. The 37 CN fuel was a blend of Canadian winter diesel fuel oil and 24% Light Cycle Oil (LCO), The four experimental fuels and one reference fuel were tested at four load levels at each of three engine speeds. The performance and combustion characteristics were compared with the physical and chemical fuel properties.

Two Canadian tar sands derived experimental diesel fuels with cetane numbers of 26 and 36 and a reference fuel with a cetane number of 47 were tested in a Deutz (F1L511D), single cylinder, A stroke, naturally aspirated research engine. The fuels were tested at intake and cooling air temperatures of 30 and 0°C. The 36 cetane number fuel was tested with advanced, rated and retarded injection timings. Poor engine speed stability at light loads and excessive rates of combustion pressure rise were experienced with the lowest cetane number fuel. Detailed performance/combustion behavior is presented and a correlation with fuel structural composition is made. The analytical techniques used to characterize the fuels included liquid chromatography, gas chromatography mass spectrometry (GC-MS) and proton nuclear magnetic resonance spectrometry (PNMR).

The Enhanced/Synthetic Vision System (E/SVS) is a Technology Demonstrator (TD) project supported by the Chief, Research and Development of the Canadian Department of National Defence. E/SVS displays an augmented visual scene to the pilot that includes three separate image sources: a synthetic computer - generated terrain image; an enhanced visual image from an electro-optical sensor (fused as an inset); and aircraft instrument symbology, all displayed to the pilot on a Helmet Mounted Display (HMD). The synthetic component of the system provides a 40 degree vertical by 80 degree horizontal image of terrain and local features. The enhanced component digitizes imagery from electro-optic sensors and fuses the sensor image as an inset (20 degrees by 25 degrees) within the synthetic image. Symbology can be overlaid in any location within the synthetic field-of-view and may be head, aircraft, target or terrain referenced.

Reliable means for on-board detection of particulate filter failures or malfunctions are needed to meet diagnostics (OBD) requirements. Detecting these failures, which result in tailpipe particulate matter (PM) emissions exceeding the OBD limit, over all operating conditions is challenging. Current approaches employ differential pressure sensors and downstream PM sensors, in combination with particulate filter and engine-out soot models. These conventional monitors typically operate over narrowly-defined time windows and do not provide a direct measure of the filter’s state of health. In contrast, radio frequency (RF) sensors, which transmit a wireless signal through the filter substrate provide a direct means for interrogating the condition of the filter itself.

With the recent advancement in sensing and controller technologies architecture design of an autonomous driving system becomes an important issue. Researchers have been developing different sensors and data processing technologies to solve the issues associated with fast processing, diverse weather, reliability, long distance recognition performance, etc. Necessary considerations of diverse traffic situations and safety factors of autonomous driving have also increased the complexity of embedded software as well as architecture of autonomous driving. In these circumstances, there are almost countless numbers of possible architecture designs. However, these design considerations have significant impacts on cost, controllability, and system reliability. Thus, it is crucial for the designers to make a challenging and critical design decision under several uncertainties during the conceptual design phase.

We report on a feasibility study of an optical micro-electro-mechanical systems (MEMS) flow sensor to measure flow rate using Moiré fringe displacement of a floating element. Due to constraints on weight, power, and size for space environmental systems, the development of sensor components that minimize the equivalent systems mass (ESM) while maintaining or exceeding required specifications is highly desirable. A feature of the optical detection method is a physical separation of electrical components from the flow stream. The geometric Moiré fringe shift optically amplifies small displacements by the ratio of the fringe pitch to the movable grating pitch that is detected using an external CCD imager, providing an electrically isolated, robust, direct scheme for detecting flow from shear stress induced displacement.