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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.

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.

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.

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 Proposal of this paper is to demonstrate the diagnosis methodology based on Bayesian Net and fuzzy logic to indicate failure probability for vehicle systems and other segments, for instance medical and Aeronautic. This work was initially developed in a dissertation that has succeeded in developing a system of fault diagnosis for diesel engines and now this article demonstrated the possibility of extending this methodology to other vehicle systems and other segments science. Also extension to other areas was also added to the technique of logic that adds the advantage of supporting the fuzzy logic in complex environments, such as the vehicle approached the diagnosis, aerospace and medical.

A set of scaling laws were previously developed to guide the transfer of combustion system designs between diesel engines of different sizes [ 1 , 2 , 3 , 4 ]. The intent of these scaling laws was to maintain geometric similarity of key parameters influencing diesel combustion such as in-cylinder spray penetration and flame lift-off length. The current study explores the impact of design constraints or limitations on the application of the scaling laws and the effect this has on the ability to replicate combustion and emissions. Multi dimensional computational fluid dynamics (CFD) calculations were used to evaluate the relative impact of engine design parameters on engine performance under full load operating conditions. The base engine was first scaled using the scaling laws. Design constraints were then applied to assess how such constraints deviate from the established scaling laws and how these alter the effectiveness of the scaling effort.

A main requirement for a satisfactory function and service life of a forged powder metal connecting rod is the fatigue strength. Fatigue strength mainly depends on design, material, microstructure, and surface condition. Much work has been accomplished to optimize these factors, but still a variety of surface defects such as localized porosity, roughness, oxide penetration, decarburization, etc., can be developed during manufacturing. These surface defects impact the fatigue strength in various ways. The impact of the decarburized layer depth on the fatigue life of a forged powder metal connecting rod is the focus of this work. Several connecting rods were submitted to a Weibull test at the same loading pattern. After the fatigue tests, the connecting rods were divided into groups with different decarburized layer depths. Both Maximum Likelihood Estimates (MLE) and Rank Regression (RR) techniques were used to analyze test results from all the groups obtained.

The aggressive reduction of future diesel engine NOx emission limits forces the heavy- and light-duty diesel engine manufacturers to develop means to comply with stringent legislation. As a result, different exhaust emission control technologies applicable to NOx have been the subject of many investigations. One of these systems is the NOx adsorber catalyst, which has shown high NOx conversion rates during previous investigations with acceptable fuel consumption penalties. In addition, the NOx adsorber catalyst does not require a secondary on-board reductant. However, the NOx adsorber catalyst also represents the most sulfur sensitive emissions control device currently under investigation for advanced NOx control. To remove the sulfur introduced into the system through the diesel fuel and stored on the catalyst sites during operation, specific regeneration strategies and boundary conditions were investigated and developed.

A compact in-situ tensile stress fixture was designed for the study of the combined effects of stress and automotive environments on structural glass fiber-reinforced composite materials. With this fixture, a standardized 300 hour laboratory screening test was developed to compare the residual property loss of composite materials due to concurrent exposure to stress and environment. It is of great importance that the data gathered in the laboratory have correlation to on-vehicle (in-service) performance, and that both lab and real world data be taken with a test system (in-situ test fixtures) capable of providing accurate and consistent results under either test condition.

Gear whine in 1st gear for an automatic transmission that has been in production for nearly thirty years was identified as an NVH issue. Due to advances in vehicle level refinement, and reduction of other masking noises, the automatic transmission gear whine became an issue with the customer. Since the transmission was already in production, the improvements had to be within the boundaries of manufacturing feasibility with existing equipment to avoid costly and time consuming investment in new machines. The approach used was one of identifying optimum values of existing gear parameters to provide a reduction in passenger compartment noise. The problem was in a light truck application. Objective noise measurements were recorded for 10 transmissions from more than 50 driven in vehicles. The transmissions were disassembled and the gears inspected.

The intent of this paper is to summarize the work of the V8 power plant intake manifold radiated noise study. In a particular V8 engine application, customer satisfaction feedback provided observations of existing unpleasant noise at the driver's ear. A comprehensive analysis of customer data indicated that a range from 500 to 800 Hz suggests a potential improvement in noise reduction at the driver's ear. In this study the noise source was determined using various accelerometers located throughout the valley of the engine and intake manifold. The overall surface velocity of the engine valley was ranked with respect to the overall surface velocity of the intake manifold. An intensity mapping technique was also used to determine the major component noise contribution. In order to validate the experimental findings, a series of analysis was also conducted. The analysis model included not only the plastic intake manifold, but also the whole powertrain.

The Indirect Boundary Element Analysis is employed for developing a computational pass-by noise simulation capability. An inverse analysis algorithm is developed in order to generate the definition of the main noise sources in the numerical model. The individual source models are combined for developing a system model for pass-by noise simulation. The developed numerical techniques are validated through comparison between numerical results and test data for component level and system level analyses. Specifically, the source definition capability is validated by comparing the actual and the computationally reconstructed acoustic field for an engine intake manifold. The overall pass-by noise simulation capability is validated by computing the maximum overall sound pressure level for a vehicle under two separate driving conditions.

In assessing the sound quality of electric motors (e.g., seat, mirror, and adjustable pedal motors), the sensation of Fluctuation Strength - a measure of intensity or frequency variation - has become important. For electric motors, it is typically caused by variation in the load, creating frequency modulation in the sound. An existing method for calculating Fluctuation Strength proved useful initially, but more extensive testing identified unacceptable performance. There were unacceptable levels of both false positives and false negatives. A new method is presented, which shows improved correlation with perceived fluctuation in sounds. Comparisons are made to the previous method and improvement is shown through examples of objective-subjective correlation for both seat motor sounds and adjustable pedal motor sounds. The new method is also shown to match subjective data from which the original measure of Fluctuation Strength was derived.

Engine excitation forces have been studied in the past using one of two methods; a lumped sum or a totally distributed approach. The lumped sum approach gives the well-understood engine inherent unbalance and the totally distributed approach is used in engine CAE models to determine the overall engine response. The approach that will be described in this paper identifies an intermediate level of sophistication. The methodology implemented considers single cylinder forces on the engine block, piston side thrust and main bearing forces, and decomposes them into their order content. The forces are then phased and geometrically distributed appropriately for each cylinder and then each order is analyzed relative to know distributions that are NVH concerns, V-block breathing, block side wall breathing, and block lateral and vertical bending.

This paper summarizes results from a study on the effects of aging temperature and A/F ratio on the NOx storage capacity of a lean NOx trap. When aged at stoichiometry at 700°C, the NOx storage capacity of the NOx trap dropped considerably during the first 200 hours of aging and then at a much slower rate beyond 200 hours. The NOx storage capacity dropped more rapidly as the aging temperature increased, with the drop in capacity particularly evident between 900°C and 1000°C. The drop in NOx capacity was significantly larger for samples aged with part-time lean operation and/or part-time rich operation than for samples aged continuously at stoichiometry. The detrimental effects of lean and rich operation increased as the temperature increased. A Pt/Al2O3 model catalyst was exposed to reducing conditions at temperatures ranging from 670°C to 1041°C and then to oxidizing conditions over the same temperature range, and in-situ XRD was used to investigate Pt particle coarsening.

Controlled Auto-Ignition (CAI) combustion has been achieved in a production type 4-stroke multi-cylinder gasoline engine. The engine was based on a Ford 1.7L Zetec-SE 16V engine with a compression ratio of 10.3, using substantially standard components modified only in design dimensions to control the gas exchange process in order to significantly increase the trapped residuals. The engine was also equipped with Variable Cam Timing (VCT) on both the intake and exhaust camshafts. It was found that the largely increased trapped residuals alone were sufficient to achieve CAI in this engine and with VCT, a range of loads between 0.5 and 4 bar BMEP and engine speeds between 1000 and 3500 rpm were mapped for CAI fuel consumption and exhaust emissions. The measured CAI results were compared with those of Spark Ignition (SI) combustion in the same engine but with standard camshafts at the same speeds and loads.