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This paper describes the rapid development of the Ford GT transmission, from concept phase to production, where the technical challenges involved are implicit in the specifications provided. It presents the steps taken at a project management level to expedite development, as well as the tools used to design and rate components at the design stage. Examples of concurrent engineering are given as well as management techniques used to predict and address key risks. In addition, details of analysis and test procedures are given, underlining their contribution to the rapid introduction of the transmission to the market place.

A small-scale oxidation test for automatic transmission fluids has been developed. In the test air flow rates, temperature and catalytic activity can be closely controlled at desired levels. A test procedure for screening automatic transmission fluids is described. Data are presented illustrating the ability of the test to distinguish between different levels of oxidation resistance, the repeatability of the test, and the correlation achieved thus far with a presently used full-scale transmission oxidation test.

The SAE Recommended Practice J963 “Anthropomorphic Test Device for Dynamic Testing” describes a standard 50th percentile adult male anthropomorphic test dummy. For nearly three years the Crash Test Dummy Task Force worked with the limited data available in selecting values for the body dimensions and ranges of motion. The data for specifying the values of mass distribution were developed experimentally as was a test procedure for determining the dynamic spring rate of the thorax.

A cylindrical combustion bomb with dynamic charging system and electro-hydraulic sampling valve is used to study the effects of turbulence on hydrocarbon (HC) emissions from a quench layer and from artificial crevices. The turbulence level is varied by changing the delay time between induction of combustible charge and ignition. Propane-air mixtures were studied over an initial pressure range of 150 to 500 kPa and equivalence ratios of 0.7 to 1.4. Sampling valve experiments show that quench-layer fuel hydrocarbons are extensively oxidized within 5 ms of flame arrival under laminar conditions and that turbulence further reduces the already low level. Upper limit estimates of the residual wall layer HC concentration show that residual quench layer hydrocarbons are only a small fraction of the exhaust HC emission.

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.

THIS PAPER GIVES an overview of the aerodynamic development of a medium commercial vehicle. It deals with the setting out and achievement of the objectives of reducing aerodynamic drag as well as other aspects of aerodynamic design development such as engine cooling, heating and ventilating and sensitivity to side winds. Reference is made to measures taken to develop heater intake designs which are suitable for a low resistance vehicle with a fast attached flow over most of the forward surfaces. At the time of initial design studies, the Ford of Europe windtunnel in Cologne, West Germany, had not yet been commissioned and it was necessary therefore to adapt testing methods to suite the different windtunnels which were used at various stages of the development programme.

A process for creating a Customer Correlated, Accelerated, Life Test is presented. This process, which results in a model for predicting reliability, has been applied to a cold weather piston scuff problem. In this paper, the authors will discuss development of frequency distributions for customer environmental and operational use, establishment of customer based failure criteria, development of an accelerated test based on degradation, selection of testing strategies, data analyses, and measurement techniques.

To better reflect real world driving conditions, the EPA 5-Cycle Fuel Economy method encompasses high vehicle speeds, aggressive vehicle accelerations, climate control system use and cold temperature conditions in addition to the previously used standard City and Highway drive cycles in the estimation of vehicle fuel economy. A standard Powersplit Hybrid Electric Vehicle (HEV) system simulation environment has long been established and widely used within Ford to project fuel economy for the standard EPA City and Highway cycles. Direct modeling and simulation of the complete 5-Cycle fuel economy test set for HEV's presents significant new challenges especially with respect to modeling vehicle thermal management system and interactions with HEV features and system controls. It also requires a structured, systematic approach to validate the key elements of the system models and complete vehicle system simulations.

No two battery cells can be identical. Charging/discharging a battery pack without monitoring cell voltages or SoC (State-of-Charge) will cause cell voltages to deviate over time and the packs useable capacity to decrease quickly. To redistribute charge uniformly among cells, various cell balancing methods have been proposed in the literature. In this paper, a cell balancing method based on a single switched-capacitor is presented from a brand new perspective. Unlike the traditional balancing methods that rely on the voltage divergence criterion, this paper uses the SoC divergence criterion to shuttle charge from a highly charged cell to a poorly charged cell. Moreover, an equivalent resistance of the single-switched capacitor topology is derived in steady state. For fast cell balancing, design guidelines are provided for selecting a proper switching-time period and the capacitor parameters. Ultracapacitors are recommended to achieve this goal.

A stress durability test method that incorporates exposure to a corrosive environment has been used to evaluate the performance of adhesively bonded steel joints. For the systems examined, corrosion exposure is more damaging than exposure to humidity alone. The combination of load and corrosion exposure is substantially more severe than either alone. A method for analysis of the data and comparison of the test results for the evaluation of adhesive bond durability is proposed. The dependence of lifetime on load is defined as , where f is the ratio of applied load to initial, unexposed failure load. The exponent n provides a measure of the degree of acceleration of the interfacial degradation processes by load.

Spark knock pressure oscillations can be detected by a cylinder pressure transducer or by an accelerometer mounted on the engine block. Accelerometer-based detection is lower cost but is affected by extraneous mechanical vibrations and the frequency response of the engine block and accelerometer. The knock oscillation frequency changes during the expansion stroke because the chamber geometry is changing due to the piston motion and the burned gases are cooling. Spectrogram analysis shows the time-dependent frequency content of the pressure and acceleration signals, revealing characteristic signatures of knock and mechanical vibrations. Illustrative spectrograms are presented which yield physical insight into accelerometer-based knock detection.

A new in-line small diameter, tube and fin aluminum heat exchanger has been developed for automobile air conditioning condenser use. This condenser, while maintaining heat transfer performance, reduces weight, package volume, air flow resistance, and manufacturing complexity.

The heated fuel injectors are designed to bring up fuel temperature so as to reduce HC and CO emissions during cold start. The heated injectors are similar to regular injectors except heaters are placed near the injector inlet and outlet. The heaters, which has the ability to regulate temperature at 180 °C, transform the thermal energy to heat up the liquid fuel through the injector body. The heated injectors are required to heat up fuel to the operating temperature (e.g., 120 °F or 48.9 °C) as quickly as possible and to maintain that fuel temperature for about three minutes. However, test results indicate it takes more than two minutes for the fuel temperature to reach the desired operating temperature. Objective of this work is to find out the mechanisms controlling the slow heating process through CFD analysis. The computational domain covers the whole injector, from inlet to exit, since the heaters located near the top and bottom of the injector.

Torque converter clutch friction interface and automatic transmission fluid (ATF) temperatures, pressure difference across the clutch piston, flow through the friction material grooves, and engine crankshaft dynamic torque were measured for typical operating conditions on a running transmission. The friction coefficient, clutch unit pressure, fraction of heat rejected to ATF flowing through the grooves, and time dependent thermal response were determined. Simplified heat transfer calculations were compared with thermal data. Clutch interface temperatures were assessed as they relate to the process of friction material and ATF degradation. The inductively powered radiotelemetry system was found to be a robust and powerful tool for investigating continuously slipping clutch system performance.

Under the initiative of The United States Council for Automotive Research LLC (USCAR) [1], we have developed and run comprehensive friction tests of dual clutch transmission fluids (DCTFs). The focus of this study is to quantify the anti-shudder durability over a simulated oil life of 75,000 shifts. We have evaluated six DCT fluids, including 2 fluids with known field shudder performance. Six different tests were conducted using a DC motor-driven friction test machine (GK test bench): 1. Force Controlled Continuous Slip, 2. Dynamic Friction, 3. Speed controlled Acceleration-Deceleration, 4. Motor-torque controlled Acceleration-Deceleration, 5. Static Friction, and 6. Static Break-Away. The test fluids were aged (with the clutch system) on the test bench to create a realistic aging of the entire friction system simultaneously.

Pigmented & mineral-filled PP (PF-PP) is marketed as a potential alternative to ABS for automotive interior applications. However, PF-PP is easily damaged by scratching its surface, thus limiting its acceptance for interior applications. This study investigates the test methods to quantify the extent of scratch & mar damage, and the effect of different mineral fillers towards improving the scratch & mar resistance of PF-PP.

PROPER protection of metal parts operating as bearing surfaces, or in contact under relatively heavy loads, during the break-in period often means the difference between successful operation and failure. Various surface coatings have been investigated to discover which ones will give this protection. The authors discuss here three types of surface treatment for cast-iron and steel that do give superior wear and scuff resistance.

A running loss test procedure has been developed which integrates a point-source collection method to measure fuel evaporative running loss from vehicles during their operation on the chassis dynamometer. The point-source method is part of a complete running loss test procedure which employs the combination of site-specific collection devices on the vehicle, and a sampling pump with sampling lines. Fugitive fuel vapor is drawn into these collectors which have been matched to characteristics of the vehicle and the test cell. The composite vapor sample is routed to a collection bag through an adaptation of the ordinary constant volume dilution system typically used for vehicle exhaust gas sampling. Analysis of the contents of such bags provides an accurate measure of the mass and species of running loss collected during each of three LA-4* driving cycles. Other running loss sampling methods were considered by the Auto-Oil Air Quality Improvement Research Program (AQIRP or Program).

Rheological measurements were performed on a series of lubricants for flexible fuel vehicles, and blends of water or methanol in these oils. A series of measurements, including kinematic viscosity, viscosity at low and high shear rates, low shear viscosity under borderline pumping conditions, and density were performed on all oils and blends. The effects of mixing conditions, such as mixing speed and temperature on these properties were also studied. Viscosity increases when water emulsifies in oils. Methanol exhibits limited solubility in all oils, but more so in synthetic base oils. Viscosity tests at 248 K (-25°C) do not indicate the onset of critical pumping conditions, even at high concentrations of water or methanol. Tests at high shear rates at 323 K (50°C) suggest that water-oil emulsions are quite stable, while methanol-oil blends lose their methanol content either due to evaporation or shear-induced separation.

Serious pitfalls exist in assuming that aluminum can be reliably resistance spot welded in the “as received” mill finish or even in the chemically cleaned condition. A commercially feasible surface abrading process was developed to promote reliability with existing tooling even 90 days afterwards. A weld reliability procedure was developed to evaluate process variables, various surface treatments, electrode materials and geometry. Comparative merits of AC and DC power were investigated. With the advent of abraded surfaces, aluminum can now be resistance spot welded with confidence and the dreaded fast electrode fauling condition associated with mill finish surfaces can be substantially alleviated.