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Engineers doing squeak and rattle testing of instrument panels (IP's) have successfully used large electrodynamic vibration systems to identify sources of squeaks and rattles (S&R's). Their successes led to demands to test more IP's, i.e., to increase throughput of IP's to reflect the many design, material, and/or manufacturing process changes that occur, and to do so at any stage of the development, production, or QA process. What is needed is a radically different and portable way to find S&R's in a fraction of the time and at lower capital cost without compromising S&R detection results.

This paper explores the extent to which standard dilution tunnel measurements of motor vehicle exhaust particulate matter modify particle number and size. Steady state size distributions made directly at the tailpipe, using an ejector pump, are compared to dilution tunnel measurements for three configurations of transfer hose used to transport exhaust from the vehicle tailpipe to the dilution tunnel. For gasoline vehicles run at a steady 50 - 70 mph, ejector pump and dilution tunnel measurements give consistent results of particle size and number when using an uninsulated stainless steel transfer hose. Both methods show particles in the 10 - 100 nm range at tailpipe concentrations of the order of 104 particles/cm3.

The feasibility of using experimentally determined flow fields at intake valve closing, IVC, as initial conditions for computing the in-cylinder flow dynamics during the compression stroke is demonstrated by means of a computer simulation of the overall approach. A commercial CFD code, STAR-CD, was used for this purpose. The study involved two steps. First, in order to establish a basis for comparison, the in-cylinder flow field throughout the intake and compression strokes, from intake valve opening, IVO, to top dead center, TDC, was computed for a simple engine geometry. Second, experimental initial conditions were simulated by randomly selecting and perturbing a set of velocity vectors from the computed flow field at IVC.

Because it is common to attach plastic parts to other plastic, metal, or ceramic assemblies with mechanical fasteners that are often stronger and stiffer than the plastic with which they are mated, it is important to be able to predict the retention of the fastener in the polymeric component. The ability to predict this information allows engineers to more accurately estimate length of part service life. A study was initiated to understand the behavior of threaded fasteners in bosses molded from engineering thermoplastic resins. The study examined fastening dynamics during and after insertion of the fastener and the effects of friction on the subsequent performance of the resin. Tests were conducted at ambient temperatures over a range of torques and loads using several fixtures that were specially designed for the study. Materials evaluated include modified-polyphenylene ether (M-PPE), polyetherimide (PEI), polybutylene terephthalate (PBT), and polycarbonate (PC).

This report is a comprehensive investigation into the use of resin transfer molded glass fiber reinforced plastics in a structural application. A pickup truck cab structure is an ideal application for plastic composites. The cab is designed to fit a production Ranger pickup truck and uses carryover frame and front end structure. The cab concept consists primarily of two molded pieces. This design demonstrates extensive parts integration and allows for low-cost tooling, along with automated assembly.

Present models and methods for simulations of sheet metal forming processes are reviewed in this paper. Because of rapid progress of computer hardware, complex computations, formerly impossible to perform due to high computational cost, are now feasible. Therefore, more realistic and computational intensive models are suggested for finite elements, materials, and frictional forces. Also, simulation methods suitable for sheet metal forming processes are recommended. Four numerical examples at the end of the paper are presented to support the recommendations.

The paper briefly reviews the current and future needs for automotive electronic packaging technology and the related reliability issues. Reliability approaches based upon physics-of-failure are discussed, and an example is given to illustrate the importance of understanding the root cause of failure and the application of a state-of-the-art approach to life prediction of leadless solder joints under thermal cycling. An introduction is also given to the recent development of the CAIR (Computer Aided Interconnect Reliability) system developed at Ford for reliability prediction of solder interconnects in automotive electronic packaging. The system integrates a number of software modules using a user interface and allows for evaluation of critical design parameters within a short period of time. The system is intended to implement the “prevention mode” into the product design process to meet the increasing reliability demand and to reduce cost and cycle time.

A framework for considering trade-offs between increased costs for lightweight materials and the attendant fuel savings accruing from weight reduction is developed in this paper. Two quantitative estimates of lifetime fuel savings due to weight reduction of a vehicle are derived. For substitution on an ongoing vehicle, available data suggest savings of about 0.26 gallons for the vehicle lifetime per lb. of weight reduction. When long-term changes in vehicles follow lightweight material feasibility, a range of estimates must be quoted; viz: 0.55 to 1.07 gallons for the vehicle life per primary pound saved. Considerations of trading these fuel savings against higher costs highlights two crucial issues: (1) the percentage weight reduction achieved in the substitution and (2) fabrication cost penalties. These technical issues largely determine whether a given application saves over-all resources.

In this study, the particle emission characteristics of 10% alternative diesel fuel blends (Rapeseed Methyl Ester and Gas-to-Liquid) were investigated through the tests carried out on a light duty common-rail Euro 4 diesel engine. Under steady engine conditions, the study focused on particle number concentration and size distribution, to comply with the particle metrics of the European Emission Regulations (Regulation NO 715/2007, amended by 692/2008 and 595/2009). The non-volatile particle characteristics during the engine warming up were also investigated. They indicated that without any modification to the engine, adding selected alternative fuels, even at a low percentage, can result in a noticeable reduction of the total particle numbers; however, the number of nucleation mode particles can increase in certain cases.

The P2000S body structure was designed as part of an advanced research project to determine the feasibility of a high volume, lightweight sport utility vehicle (SUV) that would achieve performance targets of the newly emerging “City SUV” market by developing a unitized (no frame) SUV body structure fabricated principally of aluminum. In order to be viable, this body structure was required to meet all safety, durability, NVH and other functional attributes of a truck while having the ride characteristics of a sedan. This paper describes the P2000S body structure including the structural philosophy, project constraints on the design, manufacturing processes, supporting analyses, assembly processes and unique material and design concepts which resulted in the 50% body structure weight reduction in comparison to similar sized body-on-frame production steel sport utility vehicles.

Speciation of sulfurous acid, sulfuric acid and ammonium sulfate collected from the aerosol phase on a Fluoropore filter has been readily accomplished using techniques of chemical ionization mass spectrometry combined with thermal separation. Thermal separation of ammonium hydrogen sulfate from ammonium sulfate was not possible. Spectral separation of these species by selective ionization is proposed. Analysis of sulfate aerosols collected from ambient air and catalyzed vehicle emissions is described. It was found that sulfuric acid aerosol was rapidly converted to ammonium sulfate or ammonium hydrogen sulfate in the presence of ambient concentrations of ammonia. Ambient samples collected in the Detroit metropolitan area have been found to contain only trace quantities of sulfuric aicd. Sulfate samples collected from a dilution tube into which catalyzed vehicle exhaust was injected were found to contain significant quantities of ammonium sulfate in addition to sulfuric acid.

Optimizing heat protection for underbody and underhood components, using non-CFD heat transfer CAE tools, requires the estimation of local convective heat transfer coefficients. This estimate, in turn requires knowledge of the local air velocity. Currently available methods for obtaining this velocity at several vehicle locations have been impractical and expensive for use in over-the-road testing. This paper presents the design, fabrication, and field testing results of a 26 mm diameter spherical transducer which measures the local heat transfer coefficient directly. The transducer contains three thermocouples and a heater. It is calibrated to correlate the coefficient with the air velocity. Drawing less than 0.1 A, a number of them can be powered by the vehicle battery with negligible drain. The data acquisition consists of sampling three thermocouples per spherical transducer.

New European emissions legislation (Euro5) specifies a limit for Particle Number (PN) emissions and therefore drives measurement of PN during vehicle development and homologation. Concurrently, the use of biofuel is increasing in the marketplace, and Euro5 specifies that reference fuel must contain a bio-derived portion. Work was carried out to test the effect of fuels containing different levels of Fatty Acid Methyl Ester (FAME) on particle number, size, mass and composition. Measurements were conducted with a Cambustion Differential Mobility Spectrometer (DMS) to time-resolve sub-micron particles (5-1000nm), and a Horiba Solid Particle Counting System (SPCS) providing PN data from a Euro5-compliant measurement system. To ensure the findings are relevant to the modern automotive business, testing was carried out on a Euro4 compliant passenger car fitted with a high-pressure common-rail diesel engine and using standard homologation procedures.

Spot weld failures of complicated structures, such as automotive bodies, are difficult to explain using current multiaxial spot weld failure theory. After introducing the in-plane rotational failure mode, some unexplainable spot weld failures become explainable. The purpose of this report is to introduce the spot weld rotational test, its relative strengths and its response characteristics. It is found that the strength of a spot weld under the in-plane rotational mode is far below the strengths of the same spot weld under other failure modes such as in-plane tensile/shear. The work conducted in this study could be a foundation for a new generation of multiaxial spot weld failure theory development.

The Ford PROCO stratified charge engine combines the desirable characteristics of premixed charge and Diesel engines. The outstanding characteristics of premixed charge engines are their high specific output, wide speed range, light weight and easy startability but they exhibit only modest fuel economy and relatively high exhaust emissions. The desirable characteristic of the Diesel engine is its outstanding fuel economy. However, the disadvantages of the Diesel, which include noisy operation, limited speed range, exhaust odor, smoke, hard startability, and particulate emissions have tended to limit their acceptance. In the gasoline fueled, PROCO stratified charge engine, direct cylinder fuel injection permits operation at overall lean mixture ratios and higher compression ratio. These features enable the PROCO engine to achieve brake specific fuel consumption values in the range of prechamber diesel engines.

The fatigue strength of spot welds in a multi-spot-welded structure is one of the key issues of concern for achieving structural durability and optimum design in automobile industry. In this study, a global-local fatigue life prediction method is proposed to predict the fatigue life of spot welds in multi-spot-welded structures. In this method, the remote stress-strain field away from the spot-welds, calculated from a global coarse finite element model, is assumed to be acceptable, and is used to recover the stress-strain information of the spot-welds. To improve the accuracy of the remote stress-strain field, an “equivalent” spot weld element is also proposed. The method makes it feasible to predict the fatigue life of spot welds without constructing a detailed finite element model for each spot weld. The method will help reduce finite element model size and save time.

Erosion damage to automotive car bodies caused by stones and small sand particles and road debris significantly affects the appearance of paint. Painted engineering plastics as well as precoated sheet steel are affected by erosion phenomenon. Erosion of painted plastic substrates results in cosmetic concerns while that on metal substrates results in cosmetic to perforation corrosion. This work describes a laboratory simulation of erosion of painted plastic substrates by small particles on various paint and substrate types. Gloss loss was used to quantitatively evaluate erosion of painted surfaces. Wear behavior of painted plastic substrates to slag sand impact was evaluated as a function of several variables including paint type (one-component melamine crosslinked (1K) vs. two-component isocyanate crosslinked (2K)), thermal history, and coating modulus. The effect of slag sand type (particle size and chemical composition) was studied.

Vehicle emissions have been measured and the results statistically evaluated for a vehicle test fleet consisting of four Escorts and four Explorers using both a fully formulated durability fuel doped with methylcyclopentadienyl manganese tricarbonyl (MMT) at 1/32 gram Mn/gallon and the same fully formulated durability fuel without the MMT. The fleet was divided in half -- half with MMT and half without MMT doped fuel. This report covers emission measurement results at 5,000; 15,000; 50,000 and 100,000 miles of exposure to MMT doped fuel. A modified paired t-test is used to analyze the emission data obtained from all the fleet vehicles. The statistical evaluation of both feedgas and tailpipe emissions indicate that the use of MMT is detrimental to emissions of HC at the 15,000 mile; 50,000 mile and 100,000 mile levels of MMT exposure. As mileage is accumulated, the pronounced the effect on HC by the fuel additive MMT.

A number of tests were conducted on a 2.5 litre, high-speed, direct-injection diesel engine running at various loads and speeds. The aim of the tests was to gain understanding which would lead to more effective use of exhaust gas recirculation (EGR) for controlling exhaust NOx whilst minimising the penalties of increased smoke emission and fuel consumption. In addition to exhaust emission measurements, in-cylinder sampling of combustion gases was carried out using a fast-acting, snatch-sampling valve. The results showed that the effectiveness of EGR was enhanced considerably by cooling the EGR. In addition to more effective NOx control, this measure also improved volumetric efficiency which assisted in the control of smoke emission and fuel consumption. This second of two papers on the use of EGR in diesel engines deals with the effects of EGR on soot emission and on the engine fuel economy.

A number of tests were conducted on a 2.5 litre, high-speed, direct-injection diesel engine running at various loads and speeds. The aim of the tests was to gain understanding which would lead to more effective use of exhaust gas recirculation (EGR) for controlling exhaust NOx. In addition to exhaust emission measurements, extensive in-cylinder sampling of combustion gases was carried out using a fast-acting, snatch-sampling valve. The results showed that the effectiveness of EGR in suppressing NOx was enhanced considerably by intercooling the inlet charge and by cooling the EGR. A companion paper (SAE 960841) deals with the effects of EGR on soot formation and emission [1].