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Currently, 80% of European diesel passenger cars are turbocharged and as emission standards become more stringent exhaust gas recirculation (EGR) will be the primary means of suppressing oxides of nitrogen (NOx). The lighter the load the greater will be the combustion tolerance to increased EGR flow rates and hence increased NOx suppression. Automotive diesel engines using wastegated turbochargers cannot recirculate above 50% EGR without some sort of “added” device or system, which is able to displace the inlet fresh air charge. This has been demonstrated by throttling the diesel intake to reduce the fresh air inlet manifold pressure so allowing more EGR flow by virtue of a higher exhaust-side pressure due the effects of the turbocharger. The method reported here investigates a different approach to increasing the EGR rates by replacing a fixed geometry turbocharger (FGT) with a variable geometry turbocharger, (VGT).

As part of an ongoing programme of Exhaust Gas Recirculation (EGR) wear investigations, this paper reports a study into the effect of Exhaust Gas Recirculation, and a variety of interacting factors, on the wear rate of the top piston ring and the liner top ring reversal point on a 1.0 litre/cylinder medium duty four cylinder diesel engine. Thin Layer Activation (TLA - also known as Surface Layer Activation in the US) has been used to provide individual wear rates for these components when engine operating conditions have been varied. The effects of oil condition, EGR level, fuel sulphur content and engine coolant temperature have been investigated at one engine speed at full load. The effects of engine load and uncooled EGR have also been assessed. The effects of these parameters on engine wear are presented and discussed. When EGR was applied a significant increase in wear was observed at EGR levels of between 10% and 15%.

Different systems for achieving short-route cooled EGR on turbocharged and aftercooled heavy-duty diesel engines have been tested on a 12 litre 315 kW engine with 4 valves per cylinder and an electronically controlled unit pump fuel injection system. In all of these systems the exhaust gas was tapped off before the turbine, cooled and mixed with the intake air after the compressor and aftercooler. The systems differed (mainly) in the method used to set up a positive pressure difference across the EGR circuit. This was done either by the use of an exhaust back pressure valve in the exhaust, or by using a turbocharger with variable nozzle turbine (VNT) geometry, or by combining such a VNT turbocharger with a venturi-mixer that was positioned in the intake manifold such as to provide extra suction power to the EGR gas.

The dual-fuel diesel engine (D.F.D.E) is a conventional diesel engine in which much of the energy released, hence power, comes from the combustion of gaseous fuel such as natural gas. The exhaust emission characteristics of the D.F.D.E needs further refinements, particularly in terms of reduction of Unburnt Hydrocarbons (UHC) and Carbon Monoxide (CO) emission, because the concentration of these pollutants are higher than the baseline diesel engine. Furthermore, the combustion process in a typical D.F.D.E tends to be complex, showing combination of the problems encountered both in diesel and spark ignition (S.I.) engines. In this work, a computer code has been modified for simulation of D.F.D.E combustion process. This model simulates D.F.D.E combustion by using a Multi-Zone Combustion Model (MZCM) for diesel pilot jet combustion and a conventional S.I. combustion model for modelling of combustion of premixed gas/air charge.

An electronically controlled Caterpillar single-cylinder oil test engine (SCOTE) was used to study diesel combustion. The SCOTE retains the port, combustion chamber, and injection geometry of the production six cylinder, 373 kW (500 hp) 3406E heavy-duty truck engine. The engine was equipped with an electronic unit injector and an electronically controlled common rail injector that is capable of multiple injections. An emissions investigation was carried out using a six-mode cycle simulation of the EPA Federal Transient Test Procedure. The results show that the SCOTE meets current EPA mandated emissions levels, despite the higher internal friction imposed by the single-cylinder configuration. NOx versus particulate trade-off curves were generated over a range of injection timings for each mode and results of heat release calculations were examined, giving insight into combustion phenomena in current “state of the art” heavy-duty diesel engines.

The goal of the Omnium System Car (OSCAR) research project is to redesign the front compartment of the car using modular systems. These modules integrate new functionality, can carry various equipment and can optimize their positioning around the engine compartment. The modules developed in OSCAR are: 1 cooling module 2 front quarter modules 3 plenum cover module The functionality of these modules are described as well as the way they can be assembled on the car. Gains in terms of weight, cost and investments have also been investigated.

Computational fluid dynamics (CFD) has been used to investigate the influence of the injected fuel temperature on diesel combustion and emissions. A series of three dimensional, moving piston simulations were performed for four different fuel temperature scenarios involving the fuel injection rate and period. The predictions of specific fuel consumption, NOx and soot indicated that fuel temperature effects were significant only for scenario I, where the injection period was fixed and the injection rate change was in proportion to the relative change in fuel density due to the temperature change. Under these conditions it was predicted that NOx can be reduced by 10% with a 2% penalty in BSFC, for a 100K reduction in the injected fuel temperature.

The Means Industries one-way clutch is a planar ratcheting device offering technical advantages to the more conventional roller and sprag clutches which are widely used in today's automatic transmissions. The intricate shape of the notch and pocket plates would require costly milling and broaching if produced from wrought steel or a forging. These components are now being designed and manufactured with conventional powdered metal technology. Typical designs include materials such as FN-0205, FN-0208 and FN-0408. They are single pressed to a 7.0 g/cm3 density range, then sintered and heat treated to obtain the required strength and wear resistance. This paper discusses the basic design concept, design stress limits, PM material selection and processing for these one-way clutch plates.

The authors have developed a steering entropy method to easily and accurately quantify the workload imposed on drivers who are engaged in activities apart from the normal driving operations of longitudinal and lateral control. A driver's steering behavior tends to become more discontinuous while performing an activity in addition to driving. To quantify these discontinuities, steering entropy values are obtained from a time-series history of steering angle data. A special-purpose driving simulator and a test procedure have been developed that allow workload evaluations to be conducted efficiently. The simulator and test procedure were used to evaluate the additional workload incurred by 14 different types of activities. The steering entropy results were compared with a dual task method as well as a subjective evaluation method.

Aluminum metal foams are a newly developed ultra-light weight material with the ability to count for tremendous weight savings, especially in automotive applications. The P/M foaming process allows the production of two different types of components: complex shaped parts and metal foam sandwich panels. Foaming inside a mold can produce complex net-shaped parts. Examples are inserts for bumpers, pillars, or others. The metal foam sandwich process has the main advantage of enabling not only flat panels, but also true 3-dimensional shapes by e.g. deep drawing or other forming processes prior to the foaming. Valuable properties of metal foams for automotive applications are the crush energy absorption behavior and the high stiffness. The presentation reviews the properties of metal foams with respect to automotive applications.

The successful integration of P/M into a large number of subassemblies can depend on the ability to join P/M components to each other and to wrought materials. Common methods of joining metal components, such as brazing and welding, can give unexpected results when applied to P/M. The purpose of this paper is to investigate the joining of P/M components of varying hardenability, density, and composition using friction welding, high speed pulse welding, gas tungsten arc welding, and brazing. The joints are evaluated using ultimate strength, microhardness, and microstructure. The results show that solid state process, such as high speed pulse welding and friction welding are applicable to all but the highest hardenability materials. Gas tungsten arc welding has less applicability due to crack formation upon cooling. Brazing is generally applicable with most P/M materials assuming a suitable filler metal is selected.

So far in conventional automotive meter, reflection of the incident light on a cover glass is prevented by a hood and a curved cover glass. Anti-reflection coating (hereafter abbreviated as AR coating) on the surface of cover glass can offer a meter without the hood. Thin films of AR coating are uniformly deposited on a large polymethylmethacrylate substrate in an ambient atmosphere by sol-gel dip coating and cured at low temperature. The AR coated panel shows a very low reflectance. In addition, the AR coating has a high reliability for the instrument panels of automobiles. The AR coating meter offers new instrument panel design for Toyota Prius.

In Spain, one of the major problems when selecting vehicle control adaptations for the disabled is the total absence of regulations, or technical recommendations, which govern the design and assembly of the various devices available. An added problem is that traffic administrations are often unaware of the state-of-the-art of the technical aids which are now available - and how these aids are best matched to each disability. Under these circumstances, it is easy to understand the large number of difficulties which many disabled people must overcome before obtaining a driving license. This article shows an experimental tool based on the driving simulator-evaluator (SEMAV Project) developed at the Automobile Laboratory of the Polytechnic University of Valencia in Spain. This simulator-evaluator allows the optimal selection of the most adequate control adaptations - depending on the disability and the vehicle.

In this paper the first results of a project, initiated in the University of Coimbra and dealing with the conjugated influence of multiple stressors in riding passengers, are presented. A field study was conducted in public transportation buses, in which the subjective response of the occupants was collected and the physical parameters related to thermal comfort, air quality, vibration and noise were acquired. More than 250 responses to a subjective inquire were collected. Besides questioning the occupants about how they felt the different stressors, the questionnaires also have a final question related to how they felt the global comfort of the vehicle, in a five-point scale. Even if it looks too far, the final goal of this project is to obtain an general comfort index that takes into account the influence of multiple stressors, thus giving to vehicle manufacturers a tool to evaluate the performance of their models and to improve the vehicle friendliness to passengers.

An investigation of the need of engine model complexity for use in powertrain control applications is presented in this paper. The engine studied is an SI-engine, but the analysis methods could easily be adapted to a CI-engine. The different engine models investigated are a cylinder-by-cylinder engine model and a mean value engine model. The way to evaluate the engine models is to compare the dynamical behavior and how the engine affects the driveline. The analysis is made by studying the engine in the frequency and time domain. The investigation shows that the mean value engine model is sufficient for use in powertrain simulations and for powertrain control design. The dynamical behavior for the two models coincide, and the combustion pulses are well damped in the driveline (powertrain without engine). A less complex structure is preferable when designing a control system.

Recent changes in impact protection requirements have led to increased padding on vehicle interior surfaces. In the areas near the driver's head, thicker padding can reduce the available headspace and may degrade the driver's perception of headroom. A laboratory study of driver headroom perception was conducted to investigate the effects of physical headroom on the subjective evaluation of headroom. Ninety-nine men and women rated a range of headroom conditions in a reconfigurable vehicle mockup. Unexpectedly, driver stature was not closely related to the perception of headroom. Short-statured drivers were as likely as tall drivers to rate a low roof condition as unacceptable. Statistical models were developed from the data to predict the effects of changes in headroom on the percentage of drivers rating the head-room at a specified criterion level.

An increasing emphasis is being placed in the vehicle development process on transient operation of engines and vehicles, and of engine/vehicle integration, because of their importance to fuel economy and emissions. Simulations play a large role in this process, complementing the more usual test-oriented hardware development process. This has fueled the development and continued evolution of advanced engine and powertrain simulation tools which can be utilized for this purpose. This paper describes a new tool developed for applications to transient engine and powertrain design and optimization. It contains a detailed engine simulation, specifically focused on transient engine processes, which includes detailed models of engine breathing (with turbocharging), combustion, emissions and thermal warm-up of components. Further, it contains a powertrain and vehicle dynamic simulation.

This paper describes the work done to develop an environmentally friendly coating which provides corrosion protection to fasteners and stamped parts. It is a water based, neutral pH, VOC compliant coating that contains zinc and aluminum metal flakes in an inorganic binder system. It is free of all highly regulated heavy metals and carcinogens. The coating can be applied by either dip-spin, dip-drain or spray coating processes, resulting in a dry film thickness of 0.3-0.4 mils (7.5-10 microns) which is silver in color. Curing of the coating utilizes conventional industrial ovens and has a wide cure window. The structure of the coating, mechanisms of corrosion protection, and test results will be presented.

A set of models for the prediction of mechanical efficiency as function of the operating conditions for an automotive spark ignition engine is presented. The models are embedded in an integrated system of models with hierarchical structure for the analysis and the optimal design of engine control strategies. The validation analysis has been performed over a set of more than 400 steady-state operating conditions, where classical engine variables and pressure cycles were measured. Models with different functional structures have been tested; parameter values and indices of statistical significance have been determined via non-linear and step-wise regression techniques. The Neural Network approach (Multi Layer Perceptrons with Back-Propagation) has been also used to evaluate the feasibility of using such an approach for fast black-box modelization.

An experimental methodology and test facility has been developed to perform measurements of internal sound pressure radiated from expansion devices in refrigerant. The experimental test facility is designed to help attenuate reflected sound waves and minimize both vibrations to the test section and other flow disturbances. Measurements are made using microphones mounted flush to the inner wall of the refrigerant tube and the two-microphone technique is used to account for unattenuated reflections. Results show that expansion noise is related to system operating conditions. When vapor flow is present, the far field expansion noise is significant white noise over the audible frequency range. Downstream screens were found to significantly reduce the noise generated. Also, internal sound pressure attenuation with distance has been measured and the results agree closely with theoretical predictions for visco-thermal attenuation.