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The United States Field Trial was chartered by the United States Council for Automotive Research/Vehicle Recycling Partnership (USCAR/VRP) with the objective of evaluating the feasibility and viability of collecting and recycling automotive polymers from domestic End-of-Life Vehicles (ELVs). European concerns regarding vehicle abandonment risks, decreasing landfill capacity, and disposal practices have resulted in the legislated treatment of ELVs in Western Europe. The emergence of attendant material collection schemes promoting material recycling may not apply to the free-market economic conditions prevalent in North America vehicle recycling infrastructure. Although ELVs are among the most widely recycled consumer products, 15-25% of their total mass is currently discarded with no material recovery, although their residue, when permitted, is a preferred landfill day cover in some areas.

In recent years, increased attention has been focused on the effect on the environment of Internal Combustion Engines particularly concerning emissions. Natural gas (NG) is an effective alternative to gasoline and diesel fuel in many internal combustion engine applications. Natural gas has a high research octane number (RON>130), which allows combustion at higher compression ratios without knocking. One of major benefits of using Natural gas, as an engine fuel is reduced emissions. Lean burn natural gas fuelled spark ignition engines are particularly attractive regarding environmental performance. Another benefit of lean operation is increased thermal efficiency due to an increase in the ratio of specific heats for lean mixtures.

When hydrogen is added to a gasoline fueled spark ignition engine the lean limit of the engine can be extended. Lean running engines are inherently more efficient and have the potential for significantly lower NOx emissions. In the engine concept examined here, supplemental hydrogen is generated on-board the vehicle by diverting a fraction of the gasoline to a plasmatron where a partial oxidation reaction is initiated with an electrical discharge, producing a plasmatron gas containing primarily hydrogen, carbon monoxide, and nitrogen. Two different gas mixtures were used to simulate the plasmatron output. An ideal plasmatron gas (H2, CO, and N2) was used to represent the output of the theoretically best plasmatron. A typical plasmatron gas (H2, CO, N2, and CO2) was used to represent the current output of the plasmatron. A series of hydrogen addition experiments were also performed to quantify the impact of the non-hydrogen components in the plasmatron gas.

In this work an experimental analysis is performed to evaluate the influence of different flow bench test conditions and system configurations on the flow characteristics in the intake system of a high performance 4-valve, SI Internal Combustion Engine: valve lift, test pressure drop, throttle valve aperture, throttle valve opening direction in respect to the intake system layout (i.e. clockwise/counterclockwise), presence of the tumble adaptor. To this aim, experimental tests are performed on a Ducati Corse racing engine cylinder head, by measuring the discharge coefficient and the tumble coefficient. The several experimental data obtained by combining the different operational and geometrical parameters are analysed and discussed.

Reliability of electronic components assembly mounting technologies used on multilayer alumina substrates has been investigated for Electronic Control Units (ECU's), specifically for use in harsh locations, such as under the hood or directly attached to the transmissions of automobiles. The technology mainly consists of lead-free solder and bare chip assembly. Reliability evaluation tests have been performed in a practical, severe environment, similar to under the hood of automobiles. The experiments mainly consist of thermal cycling and corrosion tests. Computer simulation techniques have also been conducted in order to obtain accurate prediction of product lifetime. The estimated lifetimes of the lead-free solders agree fairly well with the experimental results. Through these studies, ECU's with higher reliability have been applied to automatic transmissions of commercial passenger vehicles.

A standardized quasi-static dent test has been used in evaluating the dent resistance of automotive body panels for many years. In order to predict the onset of a visible dent, cyclic loading with small load increments was adopted into standard automotive test procedures. Although researchers have investigated the effects of sheet thickness, yield strength, strain aging and prestrain on the static dent resistance of sheet steel in the past, material bending and hardening effects on static dent resistance were assumed to be inconsequential, and were therefore largely ignored. In this study, the impacts of material bending and hardening on static dent resistance are investigated. A fixed load, single loading condition was carefully designed for different materials and incorporated into the quasi-static dent test. For comparison, the incremental quasi-static loading condition is also examined.

The increasing use of aluminum in the design of Body In White (BIW) structures created the need to develop and verify repair methodologies specific to this substrate. Over the past century, steel has been used as the primary material in the production of automotive BIW systems. While repair methods and techniques in steel have been evolving for decades, aluminum structural repair requires special attention for such common practices as welding, mechanical fastening, and the use of adhesives. This paper outlines some of the advanced verification and testing methodologies used to develop collision repair procedures for the aluminum 2003 Jaguar XJ sedan. It includes the identification of potential failure modes found in production and customer applications, the formulation of testing methodologies, CAE verification testing and component subsystem prove-out. The objective of the testing was to develop repair methodologies that meet or exceed production system performance characteristics.

Recent studies have shown that high-intensity discharge (HID) headlamps provide visual benefits to the vehicle operator that may lead to increased nighttime driving safety. An experimental field investigation is described that further investigates the visual performance aspects of HID forward lighting systems to isolate and examine the role of lamp spectral distribution under realistic nighttime driving conditions. This study examines lamp spectral distribution by direct comparison of HID source spectra to one that simulates a conventional halogen source. Two additional lamp spectra are also included in this study, a “cool” distribution with a high percentage of short wavelength visible light and a “warm” distribution with a high percentage of long wavelength visible light. Subjects perform a visual tracking task, cognitively similar to driving, while seated in the driver's seat of a test vehicle.

Future AFS regulation will allow change of the low beam light distribution pattern. In order to propose AFS functions inside the headlamp, several approaches can be taken: combining multisource reflectors, or changing shields within a projector system. The first possibility requires many bulbs and dedicated reflectors that have a strong impact on cost and size. The second is a more compact solution with a projector system, using a rotating horizontal drum holding specific shields. Such a design allows easy integration into the elliptical module, but generates constraints regarding accuracy of the positioning of optical components. Also, glare can be generated during transitory phases in between function changes.

The majority of first-generation Spark Ignition Direct Injection (SIDI) engines use Side-Injection, High Pressure Direct Injection (HPDI) combustion systems. Central-Injection is emerging as an alternative second-generation system. Side-Injection systems have an advantage in injector and spark plug packaging and cooling. Emission control systems are available for meeting current Japanese and European regulations. Central-Injection systems require the injector and spark plug to be closely spaced in the hotter and more crowded valve bridge area. This can pose potential development challenges with injector deposits and spark plug fouling. A potential benefit of Central-Injection is improved containment of the charge within the piston bowl, without wall guiding, resulting in lower emissions for future applications. This paper presents results from three different engines used to assess Central-Injection as a second-generation SIDI technology.

An experimental investigation has been carried out to study the effects of using exhaust gas recirculation, EGR, on the combustion pressure rise rate and thermal efficiency of a dual fuel engine running on diesel and compressed natural gas. The maximum pressure rise rate during combustion is presented as a measure of combustion noise. Experimental data from the dual fuel engine with EGR has revealed the noise generated from combustion and thermal efficiency at different EGR ratios. A Ricardo E6 diesel engine was converted to run on dual fuel of diesel and compressed natural gas and an exhaust gas recycling system is used throughout the work. The engine was fully computerized and the cylinder pressure data, crank angle data are stored in a PC for off-line analysis. The effects of EGR ratio, engine speeds, loads, temperature of recycled exhaust gases, intake charge pressure, and engine compression ratio on combustion noise and thermal efficiency were examined for the dual fuel engine.

This paper describes a two-year programme of research conducted by the authors investigating HCCI in direct injection gasoline engines. Poppet-valved two-stroke cycle operation has been investigated experimentally, using conventional gasoline compression ratios and fuel, and ambient temperature intake air. Extensive combustion and emissions data was gathered from the experimental engine. Computational Fluid Dynamics (CFD) has been used to model HCCI combustion, and the CFD tool validated using experimental data. Based on experience with the two-stroke engine and modelling techniques, a four-stroke engine has been designed and tested. Using this range of tools, practical options for gasoline HCCI engines are evaluated, and a scenario for the market introduction of HCCI is presented.

Compression ignition delay of DME is studied theoretically. Physical phenomena that would influence the ignition delay, characteristics of the DME spray and evaporation of DME droplets in the spray, are analyzed. It is found that the short ignition delay of DME revealed in engine tests is due largely to the short physical delay of DME: The evaporation rate of DME droplets is about twice that of diesel-fuel droplets at the same cylinder condition and, the stoichiometric mixture in a DME spray can be established immediately - in comparison, the stoichiometric mixture in a diesel-fuel spray cannot be established before temperatures of diesel-fuel droplets become higher than 225 °C. The high droplet evaporation rate of DME is also responsible for the irregular boundary and tip of the DME spray as observed by many investigators. On the basis of experimental data reported in the literature, cetane number of DME is estimated to be 68.

In this study, spray images of LPG Blended Fuels (LBF) for DI diesel engines were observed using a constant volume chamber at high ambient temperature and pressure, and the spray characteristics of the fuel were investigated. The LBF spray started to vaporize at the injector tip and the outer downstream regions of the spray, like diesel fuel, because of the high temperature at these areas. There were more vaporized areas compared to diesel fuel. Sufficient fuel injection volume and volatility of LBF resulted in good fuel-air mixture, then, THC emissions decreased compared to diesel fuel at high load engine test conditions. Butane spray image could not be observed at the injector tip. It seems that the high temperature of the injector tip caused the butane spray to vaporize rapidly. Spray tip penetration with LBF and butane were equal or greater than with diesel fuel. The high volatility of LBF and butane had no noticeable effect on spray penetration.

A novel chemical non-equilibrium model and computer code for the calculation of the combustion and ionization in the cylinder of Spark Ignition (SI) gasoline engine were developed and presented at SAE 2002 World Congress. It was the only model which gave the chance to predict two peaks of ion current as a result of chemical and thermal ionization of combustion products. Chemical non-equilibrium approach, detailed modeling of combustion and flame front propagation, the possibility to predict very small concentrations of combustion products (molar fraction down to 10 - 28) including ions and electrons and independence from quantity and type of substances and chemical reactions provided the universal and powerful tool for the numerical investigation of sophisticated processes occurred during the working (power) stroke.

Using an implicit transient FEA models of an intake engine valve, the dynamic stress/strain response of a valve closing (impact) on the valve seat was simulated. Key dynamic events during the closing process were identified and their corresponding physics accounted for in the model including: valve seat contact, valve tilt, rocker arm separation, material properties, shock wave and stem seal damping. Empirical tests were conducted to characterize the stem seal damping as a function of valve stem velocity. In addition, a simplified dynamics equation approach was developed. The results were successfully correlated to recorded strain gauge data.

This paper reviews the state of the art of CAE simulation and analysis methods on disc brake squeal. It covers complex modes analysis, transient analysis, parametrical analysis, and operational simulation. The advantages and limitations of each analysis method are discussed. This review can help analysts to choose right methods and decide new lines of method development. For completeness, analytic methods dealing with continuum models are also briefly covered. This review was made from those papers that the authors are familiar with. It is not meant to be all-inclusive even though the best possible effort has been attempted.

The changes of dynamic frequency response, commonly used to determine the dynamic characteristic of built-up structures, were studied over the entire fatigue failure process for tensile-shear spot-welded joints. The results of an experimental study showed that the natural frequency varies non-linearly with the fatigue damage fraction. This behavior was modeled using finite element analysis of a progressively growing crack, initiating at the joining surface, then progressing to the outside surface of the specimen, and finally extending from the spot weld nugget. The relationship between dynamic frequency response and crack propagation may be applied to study effect of aging (high mileage) in NVH quality.

Although the toroidal continuously variable transmission (CVT) has been successfully introduced into the automotive market, it has not been developed for the motorcycle community even though manufacturers have shown interest. Further, little information is available with regards to their application in motorcycles. To aid in the development process, continuously variable toroidal transmission design concepts for a motorcycle application are presented. Alternate packaging configurations developed in this paper represent potential future motorcycle transmission arrangements. Variator design parameters and their effect on transmission operation are discussed. Both single and dual cavity designs as well as orientation of the engine and final drive are reviewed.

A one-dimensional, two layer computational model was developed to predict the behavior of a clean and particulate-loaded catalyzed wall-flow diesel particulate filter (CPF). The model included the mechanisms of particle deposition inside the CPF porous wall and on the CPF wall surface, the exhaust flow field and temperature field inside the CPF, as well as the particulate catalytic oxidation mechanisms accounting for the catalyst-assisted particulate oxidation by the catalytic coating in addition to the conventional particulate thermal oxidation. The paper also develops the methodology for calibrating and validating the model with experimental data. Steady state loading experiments were performed to calibrate and validate the model.