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Thermal barrier coated diesel engines, also known as low heat rejection (LHR) engines, have offered the promise of reducing heat rejection to the engine coolant and thereby increasing overall thermal efficiency. However, the larger market potential for thermal barrier coated engines may be in retrofitting in-service diesel engines to reduce particulate emissions. Prior work by the authors has demonstrated a significant decrease in particulate emissions from a thermal barrier coated, single-cylinder, indirect injection (IDI) diesel engine, primarily through reduction of the volatile (VOF) and soluble (SOF) fraction of the particulate. This prior work relied on conventional, commercially available, petroleum-based lubricants. The present study concerns the additional benefits for particulate reduction provided by vegetable oil lubricants. These lubricants are derived from renewable resource materials and can provide a reduction in lubricant generated particulate matter.

Thick optical waveguides (or “light pipes”) which utilize aspheric surfaces are shown to greatly improve illumination system efficiency over those that use linear or spherical surfaces only. An aspheric collection optic that is tailored to the filament of a particular bulb is demonstrated. Bending light around a ninety degree turn is also investigated, and the use of aspheric surfaces is once again shown to be more effective than linear or spherical mirrors. Optical design software is used to provide illustrative examples of general problems and solutions that are often encountered in waveguide illumination system design.

This paper deals with the analysis of heat release characteristics of an insulated turbocharged, six cylinder, DI contemporary diesel engine. The engine is fully insulated with thin thermal barrier coatings. Effect of insulation on the heat release was experimentally verified. Tests were carried over a range of engine speeds at 100%, 93%, 75% and 50% of rated torque. Fuel injection system was instrumented to obtain injection pressure characteristics. The study shows that rate of heat release, particularly in the major portion of the combustion, is higher for the insulated engine. Improvement in heat release and performance are primarily attributed to reduction in heat transfer loss due to the thin thermal barrier coating. Injection pressure at the rated speed and torque was found to be 138 MPa and there was no degradation of combustion process in the insulated engine. Improvements in BSFC at 93% load are 3.25% and 6% at 1600 and 2600 RPM, respectively.

Medium-carbon, microalloyed forging steels represent a cost effective replacement of quenched and tempered grades. Their strength properties are derived from precipitation during cooling from the forging temperature. Because of the relatively high carbon content, vanadium is the most suitable addition to achieve precipitation strengthening. The effectiveness of vanadium is enhanced by the presence of nitrogen. For components subjected to impact loading, improvement in toughness is achieved by refining austenitic grains, pinning their boundaries by means of dispersed titanium nitrides. Precipitation strengthened ferrite-pearlite steels exhibit superior machinability compared to that of quenched and tempered alloy steels. As a result, the total machining costs are substantially reduced compared to the costs of machining heat-treated steels. The frequency of tool breakage and tool changes decrease dramatically, virtually eliminating line scrap and unnecessary downtime.

By-pass filtration of engine lubricating oils is now a widely used technique for controlling the cleanliness of the oil during a vehicles service interval. The two common by-pass filtration techniques used by the automotive industry being barrier media filtration and self-driven centrifugal oil cleaners. In general it can be said that the fundamental operating principles of a centrifugal oil cleaner are poorly understood by others. The aim of this paper is to raise the general level of understanding of centrifugal oil cleaners and to aid lubrication system designers in the comparison of these devices with other filtration techniques. This paper initially discusses the reasoning behind by-pass oil filtration and then goes on to assess some of the fundamental operating parameters which need to be addressed when fitting a self-driven by-pass centrifugal oil cleaner.

The next generation of cabin air filters will include the ability to remove not only particulate matter, but odors as well. A key element in the development of odor removal filters is the design of laboratory tests to predict in-service performance. The studies described in this report used a combination of subjective and objective test methods to evaluate a series of odor-removal filters for their ability to remove environmentally significant reduced sulfur compounds. The work was performed in two parts. In the first part the detection, recognition, and annoyance thresholds for hydrogen sulfide and methyl mercaptan were measured using a 37-member odor panel. The second part consisted of a group of tests in which the contaminant concentrations upstream and downstream of six types of filters were measured using an instrumental method.

A comprehensive strategy to investigate the role of the body mounts on the passenger compartment response in a frontal crash event is presented. The activities of the study include quasi-static vehicle crush testing, development of a component-level dynamic body mount test methodology, lumped-mass computer modeling, as well as technical analysis. In addition, a means of investigating the effects the body mounts have on the passenger compartment response during a frontal barrier impact is addressed.

The performance comparison between different filters requires a test method with repeatable results and low variability. The current SAE J1669 standard does not address some issues related to the measurement of the fractional efficiency of dust loaded filters. This inadequate test procedure can contribute to the unacceptable measurement variability. This paper highlights some of these issues. The influence of media structure, flow rate and amount of dust loading on efficiency measurement is investigated and discussed. The impact of particle shedding on fractional efficiency measurement and variability found to be critical.

Car side doors are one of the most complex parts of the body, because this component has to meet a lot of requirements. Independent of the material - steel, aluminum, magnesium, or fiber-reinforced plastics (FRP) - there are multiple important requirements. In this paper, testing methodologies for self-supporting car side doors made from FRP are presented based on different conceptual design studies using these innovative materials. These doors and related testing methodologies have been developed in joint research and pre/advanced-development projects with different partners, car manufacturers as well as suppliers. The importance and benefit of benchmarks, advanced experimental material analysis, substructure and full-size component testing in the product development process is discussed. Furthermore important links to the CAE-process are referred and the significant value on the whole development process is demonstrated.

Computer simulation modelling has become one of the cornerstones for automotive safety vehicle development. The desire to shorten vehicle design schedules, as well as reduce prototype build and test cycles, is driving the need for more useful and accurate simulation models. This paper discusses testing techniques for two commonly used types of models; Lumped Mass/Spring and Occupant Response Simulation. These models are used for vehicle structure and interior component and restraint development, respectively. Although these types of simulations are not new to the industry, both the actual models and testing techniques used to generate input data have been gradually improved throughout the years. Readers of this paper will gain a broader understanding of the usefulness of these models, as well as the component testing which is done to build a valid simulation.

Originally designed for measuring closed-loop contours such as those around a human thorax, the External Peripheral Instrument for Deformation Measurement (EPIDM), or chestband, was developed to improve the measurement of dummy and cadaver thoracic response during impact. In the closed-loop configuration, the chestband wraps around on itself forming a closed contour. This study investigates the use of the chestband for dynamic deformation measurements in an open-loop configuration. In the open-loop configuration, the chestband does not generally form a closed contour. This work includes enhanced procedures and algorithms for the calculation of chestband deformation contours including the determination of static and dynamic chestband contours under several boundary conditions.

Ball and Tripod constant velocity joints are used in the majority of today's automobiles. The tribology of both types is complex. The low speed variable sliding and rolling motions with sinusoidal variation of amplitude and track surface conditions having typical Ra values of 0.4 to 4μm give rise to low λ-ratios. Contact conformities are above the level at which Hertz contact mechanics can normally be applied. These factors, plus the introduction of new joints, demands from downsizing and the search for improved refinement has lead to the development of new high-performance greases to provide effective, filled-for-life lubrication.

A multi-objective optimization procedure has been developed to optimize the vehicle longitudinal acceleration and steady-state fuel economy. A 5-speed manual-transmission vehicle is adopted for the prediction of the 0 - 60 mph acceleration time. A simplified fuel economy model is used to simulate the fuel consumption under steady vehicle speed. The optimization algorithm selected is the Modified Method of Feasible Directions due to its high reliability and efficiency. A notable feature of the optimization process adopted is that the algorithm can compromise between the competing performances while meeting the requirements for the ride and handling quality of the vehicle.

Technologies for reducing fuel consumption have attracted strong interest in recent years amid the heightened concern about global environmental protection. At Nissan, we have been focusing on the development of electronically controlled continuously variable transmissions (CVTs) since the early 1980s as a promising technology for reducing fuel consumption. That work has led to the commercialization of the world's first belt-drive CVT that is suitable for application up to 2.0-liter class passenger cars. The practical use of CVTs has so far been limited to cars mounted with small displacement engines of the 1.6-liter class. The belt-drive CVT described here incorporates new technology for transmitting greater torque and also has product attributes suitable for use on upscale passenger cars, making it applicable to 2.0-liter class models.

A fixed ball Constant Velocity joint has been developed and optimized specifically for automotive driveshafts with articulation angles greater than those permissible with cardan joints. The joint was developed both as an NVH solution to cardan joints and as a lightweight replacement for the centered double cardan joint which exists in many light truck applications today. The joint offers NVH improvements against cardan joints due to its CV nature, and significant improvement when compared to centered double cardan driveshafts because of reduced overhang, improved runout control, compact design and a 20% weight reduction. Internal geometry of the joint has been optimized to minimize heat generation during operation. The joint has been successfully endurance tested running at 75 kilowatts at angles of 10.

An advanced numerical model is proposed to analyze the power transmitting mechanisms of a CVT using a metal V-belt. By using the present model, forces acting on the belt are well estimated not only at steady states but also during transitional states where the speed ratio is changing. The numerical results show that blocks are in compression in both strands when the speed ratio is rapidly shifted. A complementary model is also developed to analyze the load distribution among bands which form the ring. The load distribution in the ring is governed by the difference in coefficients of friction among elements.

At first, the dynamic electromagnetic characteristics of a pulsed solenoid valve is analyzed by experiments. The fast valve response is obtained by material modifications. Then, the intelligent solenoid driving method is discussed. The new techniques of the “active” PWM and the “d2i/dt2” detection are developed for feedback control of the solenoid holding current and the valve closure timing. Finally, the control and diagnosis method for the valve closure duration is investigated. A sensing mechanism utilizing momentary camshaft speed fluctuations of fuel injection pump is presented, which provides the basis for feedback control and diagnosis of the valve closure duration and diesel fuel injection process.

Typical fuel metering systems for small gas turbine engines consist of a metering valve and a bypass valve which is maintaining a constant differential pressure across the metering valve orifice. The metering valve is operated by the compressor pressure signal and the bypass valve acts automatically. It is proposed to bring both the metering and the bypass valves under the control of two digital linear actuators. The first one would move the metering plunger according to the compressor pressure and the second would move the bypass plunger in such a way, that the differential pressure across the metering orifice would be maintained constant only during steady state engine operation. During the engine transient processes, however, it would be increased or decreased as required, to speed up the change in the nozzle flow rate and consequently the engine dynamic response.

An enlarged transparent model of a six-hole vertical diesel injector has been manufactured in order to allow flow measurements inside the sac volume and the injection holes to be obtained using a combination of laser Doppler velocimetry (LDV) and the refractive index matching technique under steady state conditions. The measurement points were concentrated in the sac volume close to the entrance of the injection holes as well as inside them on a vertical plane passing through the axis of two injection holes for two different needle lifts. The velocity flow field was characterized in terms of the mean velocity and the turbulent intensity. The results revealed that, under certain conditions, cavitation may occur in the recirculation zone formed at the entrance to the hole since the pressure in this region can reach the value of the vapor pressure of the flowing liquid; this was found to strongly depend on the needle lift and eccentricity.

In an effort to protect the earth's environment, emission regulations in the diesel engine field are becoming increasingly strict. One way of meeting these regulations is to atomize the fuel spray by using a fuel injection system with high-pressure injection, which activates engine combustion. With current in-line pump systems, however, it is still possible to satisfy the demand for cleaner emissions by improving the fuel spray, through measures such as reviewing high-pressure injection and initiating improvements in the nozzle. This report describes the new in-line pump system for medium duty diesel engines to meet future emission regulations. In this report, we will describe how analytical technology, such as computer simulation, was used on the pump side to make improvements for higher injection pressure.