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Two-stroke cycle direct injection engines can achieve adequate stability at idle with stratified combustion at very lean overall air-fuel ratio, but exhaust temperature is very low. A rotary valve system was designed to spill charge from the cylinder into the intake tract during the compression stroke, in order to allow stable operation at lower engine delivery ratio and thereby increase exhaust temperature. Reduction of the engine delivery ratio was not achieved due to the poor scavenging characteristics of the swirl liners used, which resulted in high content of exhaust residual gas in the spill recirculation flow. Although the concept objective of higher exhaust temperature was not realized, the results indicate that the concept may be feasible if high purity of the spill recirculation flow can be achieved in conjunction with high trapping efficiency.

An electrochemical testing protocol for assessing the intrinsic corrosion-resistance of creep-resistant magnesium alloys in aqueous environments, and effects of passivating surface films anticipated to develop in the presence of engine coolants is under development. This work reports progress in assessing the relative corrosion resistance of the base metals (AMC-SC1, MRI-202S, MRI-230D, AM50 and 99.98% Mg) in a common test environment, based on a near-neutral pH buffered saline solution, found to yield particularly stable values for the open-circuit or corrosion potential. This approach was found to provide a platform for the eventual assessment of the durability of certain passivating layers expected to develop during exposure of the magnesium alloys to aqueous coolants.

The effects of injector targeting and fuel volatility on transient fuel dynamics were studied with a comprehensive quasi-dimensional model and compared with experimental results from Part I of this report (1). The model includes the transient, convective vaporization of four multi-component fuel films coupled with a transient thermal warm-up model for realistic valve, port and cylinder temperatures (2, 3). Two injector targetings were analyzed, first with the fuel impacting the intake valve and in addition, the fuel impacting the port floor directly in front of the intake valve. The model demonstrates the importance of both component temperature and fuel impaction area on fuel vaporization, transient air fuel ratio (AFR) response and the amount of liquid fuel entering the cylinder. Generally, a smaller injector footprint area will lead to more liquid fuel entering the cylinder even if the spray is targeted at the back of the intake valve.

The occurrence of flash boiling in the fuel spray of a Port Fuel Injected (PFI) spark ignition engine has been observed and photographed during normal automotive vehicle operating conditions. The flash boiling of the PFI spray has a dramatic affect on the fuel spray characteristics such as droplet size and spray cone angle which can affect engine transient response, intake valve temperature and possibly hydrocarbon emissions. A new method of correlating the spray behavior using the equilibrium vapor/liquid (V/L) volume ratio of the fuel at the measured fuel temperature and manifold pressure is introduced.

A review of flame kernel growth in SI engines and the regimes of premixed turbulent combustion showed that a misfire model based on regimes of premixed turbulent combustion was warranted[1]. The present study will further validate the misfire model and show that it has captured the dominating physics and avoided extremely complex, yet inefficient, models. Results showed that regimes of turbulent combustion could, indeed, be used for a concept-simple model to predict misfire limits in SI engines. Just as importantly, the entire regimes of premixed turbulent combustion in SI engines were also mapped out with the model.

A life-cycle assessment (LCA) has been developed to help compare the economic, environmental and energy (EEE) impacts of converting coal to automotive fuels in China. This model was used to evaluate the total economic cost to the customer, the effect on the local and global environments, and the energy efficiencies for each fuel option. It provides a total accounting for each step in the life cycle process including the mining and transportation of coal, the conversion of coal to fuel, fuel distribution, all materials and manufacturing processes used to produce a vehicle, and vehicle operation over the life of the vehicle. The seven fuel scenarios evaluated in this study include methanol from coal, byproduct methanol from coal, methanol from methane, methanol from coke oven gas, gasoline from coal, electricity from coal, and petroleum to gasoline and diesel. The LCA results for all fuels were compared to gasoline as a baseline case.

Rapid Prototyping, Fabrication and Tooling is a process that blends a series of technologies (machines, tools, and methods) capable of generating physical objects directly from a CAD database. The process dramatically reduces the time spent during product development by allowing for fast visualization, verification, iteration, optimization, and fabrication of parts and tools. Many new techniques of tooling have been and are being developed by using rapid fabricated parts. These are having a dramatic impact on both timing and costs throughout the automotive industry. One area that these methods can be utilized to their full potential is motorsports. Of particular interest is the growing use of bridge tooling to provide first article through production intent parts that promote cost effective changes.

There are a number of benefits from Ford Motor Company's participation in motorsports. This paper will describe how an engineering team developed a CAE process to assist in the design of a race car to meet impact requirements, with the technology transfer benefit of improved impact performance of composite structures in passenger cars. In 1997/98, a CAE process was developed and applied in the design and test of Formula One race car composite impact structures. For this particular engineering effort, a Ford proprietary software program, COMP-COLLAPSE, was the primary analysis tool that was utilized to successfully predict impact performance. As a result, COMP-COLLAPSE was used extensively in the design of race car composite impact structures. There were two beneficiaries from this effort: Race Vehicles: Improved vehicle impact performance as well as design improvement in crush efficiency, packaging, weight, and manufacturing.

Multidimensional models that are used for engine computations must include spray sub-models when the fuel is injected into the cylinder in liquid form. One of these spray sub-models is the droplet interaction model, which is separated into two parts: first, calculation of a collision rate between drops, and second, calculation of the outcome once a collision has occurred. This paper focuses on the problem of calculating the collision rate between drops accurately. Computing the collision rate between drops or particles when they are non-uniformly distributed and sharp gradients are present in their distribution is a challenging task. Traditionally the collisions between parcels of drops have been computed using the same spatial grid as is used for the Eulerian gas-phase calculations. Recently it has been proposed to use a secondary grid for the collision rate calculation that is independent of the gas-phase grid, as is done in the NTC collision algorithm.

A new diesel engine, called the 6.7L Power Stroke® V-8 Turbocharged Diesel, and code named "Scorpion" has been designed and developed by Ford Motor Company for the full-size pickup truck and light commercial vehicle markets. It incorporates the latest design technology to meet 2010 model year emission regulations for both chassis and dynamometer-based certifications, and is compatible with up to B20 biodiesel fuel. The engine is an entirely new 90 degree V-8 design featuring inboard exhaust, piezo common rail fuel injection, a new dual compressor wheel turbocharger, and dual loop cooling systems. The 6.7L is Ford's first diesel engine designed for the North American pickup and light commercial truck market.

Hybrid electric vehicle (HEV) powertrains have become key to developing environmentally friendly and fuel efficient vehicles. As such, companies are continually investing in developing new hybrid powertrain architectures. Ford Motor Company has developed a new “Dual-Drive” full hybrid electric vehicle that overcomes some attribute deficiencies of existing hybrid powertrain architectures due to the kinematic arrangement of the engine, motors and driveline components. This hybrid powertrain is comprised of conventional powertrain components as its base with an electric motor on the rear axle, and a crank integrated starter generator, engine and transmission on the front axle. It forms a complex configuration which provides fuel economy improvement over a conventional powertrain.

A test cell was developed for evaluating a 6-speed automatic transmission. The target vehicle had an internal combustion 5.4L gasoline V8 engine. An electric dynamometer was used to closely simulate the engine characteristics. This included generating mean torque from the ECU engine map, with a transient capability of 10,000 rpm/second. Engine inertia was simulated with a transient capability of 20,000 rpm/second, and torque pulsation was simulated individually for each piston, with a transient capability of 50,000 rpm/second. Quantitative results are presented for the correlation between the engine driven and the dynamometer driven transmission performance over more than 60 test cycles. Concerns about using the virtual engine in validation testing are discussed, and related to the high frequency transient performance required from the electric dynamometer. Qualitative differences between the fueled engine and electric driven testing are presented.

FMVSS 201U, interior head impact performance is required for each new vehicle program. In the laboratory, testing to this requirement includes laying out the target locations, defining additional robustness target points based on targeting variation, positioning the Free Motion Headform (FMH), impacting each location with the headform and measuring HIC values. The tests may involve some conservative strategies and robustness studies to protect for the worst-case scenarios, where an impact might produce the highest HIC(d) within variations of impact conditions. In order to automate the best practices and procedures for both laboratory and CAE, a process automation environment was used to develop the Interior Head Impact Toolkit (IHIT, pronounced as i-hit). The IHIT software addresses several key testing processes and is grouped into four modules.

Self recirculation casing treatment has been showed to be an effective technique to extend the flow range of the compressor. However, the mechanism of its surge extension on turbocharger compressor is less understood. Investigation and comparison of internal flow filed will help to understand its impact on the compressor performance. In present study, experimentally validated CFD analysis was employed to study the mechanism of surge extension on the turbocharger compressor. Firstly a turbocharger compressor with replaceable inserts near the shroud of the impeller inlet was designed so that the overall performance of the compressor with and without self recirculation casing treatment could be tested and compared. Two different self recirculation casing treatments had been tested: one is conventional self recirculation casing treatment and the other one has deswirl vanes inside the casing treatment passage.

This paper presents an enhanced Bayesian based model validation method together with probabilistic principal component analysis (PPCA). The PPCA is employed to address multivariate correlation and to reduce the dimensionality of the multivariate functional responses. The Bayesian hypothesis testing is used to quantitatively assess the quality of a multivariate dynamic system. Unlike the previous approach, the differences between test and CAE results are used for dimension reduction though PPCA and then to assess the model validity. In addition, physics-based thresholds are defined and transformed to the PPCA space for Bayesian hypothesis testing. This new approach resolves some critical drawbacks of the previous method and provides desirable properties of a validation method, e.g., symmetry. A dynamic system with multiple functional responses is used to demonstrate this new approach.

Ford developed the 6R140 TorqShift six-speed transmission for the Ford F-series SuperDuty trucks. The 6R140 transmission is specifically designed to manage the increased torque produced by the 6.7-liter Power Stroke V-8 turbocharged diesel engine. It is also matched with the 6.2-liter V-8 gasoline engine. By design, the new 6R140 transmission seamlessly delivers the enormous low-rpm torque produced by the new diesel engine and efficiently manages the higher rpm of the new gasoline engine.

This work presents a statistical approach for simulation based on Monte Carlo method. As an exercise of the method a CAE vehicle dynamics model was specifically created to evaluate the likelihood to meet a given target driving a maneuver for given inputs variations. In the exercise, three different inputs were chosen as stochastic inputs (also called noise factors) and all relevant information about their statistics has been raised, based in components information. The chosen inputs are: front/rear dampers curves, front/rear ride heights and tire surface temperature. A brief description of the Monte Carlo technique is presented. The choice of this method is due to the reduced number of simulations required to have a given accuracy in comparison with other approaches, especially for multivariable system. As output variable for the exercise, the tire patch height was chosen and the resulting probability density function of it is presented.

Internal combustion engines are designed to meet the high power, low fuel consumption and also, low exhaust emissions. The engine running conditions is valid the concept that, the expectative is very high because of the variety of operating conditions like cold start, frequent start and stop, time high speed and load, traditional gasoline, mix of gasoline and alcohol and finally, alcohol fuel only. Considering such demand, this paper explains the relationship between the reliability bathtub curve, specifically the "Infant Mortality" portion. The bathtub curve describes failure rate as a function of time. The "Infant Mortality" portion of the curve is the initial section for which the failure (death) rate decreases with time (age). In general, these problems are related to manufacturing aspects or poor design definitions. With development of technology, hard failures, the ones that cause dependability, are becoming rare.

Internal combustion engine calibration teaching by Stand Alone System. This paper illustrates a teaching methodology for technical students of internal combustion engine calibration, by stand alone engine control unit with variable ignition and fuel injection time. Using a system named HIS (Stand alone Electronic Control Unit), to change the engine parameters, as fuel injection time and ignition time, the students can optimize fuel consumption, performance and exhaust emission. The tests are developed using the DOE (design of experiments) technique of artificial intelligence.

The behavior knowledge of the vehicle on uphill maneuvers - startability on grade, is an important metric for sizing powertrain components, such as the engine torque, clutch, first and reverse gear ratios, final drive and tire sizes. During the uphill maneuver, all components of the powertrain are subject to efforts that determine the vehicle performance in this condition. The analysis of this maneuver, for a front-wheel-drive vehicle, is evaluated in this article, through a correlation of a computer program developed in Matlab-Simulink, with experimental measurements performed on the vehicle at the track, becoming an important tool for analysis of passenger vehicles subject to these conditions present on Brazilian streets.