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Natural luminosity (NL) and chemiluminescence (CL) imaging diagnostics are employed to investigate fuel-property effects on mixing-controlled combustion, using select research fuels-a #2 ultra-low sulfur emissions-certification diesel fuel (CF) and four of the Fuels for Advanced Combustion Engines (FACE) diesel fuels (F1, F2, F6, and F8)-that varied in cetane number (CN), distillation characteristics, and aromatic content. The experiments were performed in a single-cylinder heavy-duty optical compression-ignition (CI) engine at two injection pressures, three dilution levels, and constant start-of-combustion timing. If the experimental results are analyzed only in the context of the FACE fuel design parameters, CN had the largest effect on emissions and efficiency.

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.

The pneumatic air brake system for heavy commercial trucks is composed by a large number of components, aiming its proper work and compliance with rigorous criteria of vehicular safety. One of those components, present along the whole vehicle, is the air brake tube, ducts which feed valves and reservoirs with compressed air, carrying signals for acting or releasing the brake system. In 2011, due to a lack of butadiene in a global scale, the manufacturing of these tubes was compromised; as this is an important raw material present on the polymer used so far, PA12. This article introduces the methodology of selecting, developing and validating in vehicle an alternative polymer for this application. For this purpose, acceptance criteria have been established through global material specifications, as well as bench tests and vehicular validation requirements.

Power Split Hybrids are unique when compared to conventional powertrains from the perspective that the engine speed is directly controlled by the motor/generator at all times. Therefore, traditional methods of detecting variations in fuel volatility do not apply for Power Split Hybrid based configurations. In their place, the Ratio-metric Fuel Compensation (RFC) method has been developed for Power Split Hybrid generator configurations to detect and compensate for engine hesitations within milliseconds of the first injection event. Furthermore, test results have shown that in the presence of low volatility fuel, RFC provides robust starts at the ideal lean air fuel ratio required for PZEV emissions compliance.

This article is a new methodology to create a strong and reliable procedure to measure oil level at dealers. Most of time, commercial trucks run full loaded. Engine oil level indication systems are designed to measure oil level at that condition. However commercial trucks are assembled and sold empty and without bodies for trucks. In result of this condition, vehicles with a false indication of low engine oil level are detected at dealers' pre-delivery inspection, resulting in oil addition. This oil addition causes unnecessary costs, since vehicles are produced with maximum oil level. The methodology presented in this study analyzes and treats all variables involved in engine oil level measurements from engine production line until dealers' pre-delivery inspection

Exhaust gas air-fuel ratio (A/F) sensors are common devices in powertrain feedback control systems aimed at minimizing emissions. Both resistive (using TiO2) and electrochemical (using ZrO2) mechanisms are used in the high temperature ceramic devices now being employed. In this work a new mechanism for making the measurement is presented based on the change in the workfunction of a Pt film in interaction with the exhaust gas. In particular it is found that the workfunction of Pt increases reversibly by approximately 0.7 V at that point (the stoichiometric ratio) where the exhaust changes from rich to lean conditions. This increase arises from the adsorption of O2 on the Pt surface. On returning to rich conditions, catalytic reaction of the adsorbed oxygen with reducing species returns the workfunction to its original value. Two methods, one capacitive and one thermionic, for electrically sensing this workfunction change and thus providing for a practical device are discussed.

This paper reviews the design and development of a self-filling, in-tank fuel system reservoir intended for use in diesel engine vehicle applications. This new idea eliminates engine driveability concerns (stumbles, hesitations, stalling, etc.) associated with an inconsistent supply of fuel from the fuel tank to the engine, particularly during sudden vehicle maneuvers and with low fuel tank conditions.

A new, systematic, sensitivity based design process for weight reduction is presented. Traditionally, a trial and error method is used when a design fails to meet the weight and the design criteria, which often conflict. This old approach not only is time and cost consuming but also does not provide insight into structural behavior. This proposed process uses state-of-the-art technologies such as design sensitivity analysis, numerical optimization, graphical user interface, etc. It handles multi-discipline design criteria simultaneously and provides design engineers insight into structural responses for frequency, durability, and stiffness concerns and a means for systematic weight reduction and quality improvement. The new design process has been applied for the weight reduction of advanced truck frame designs. Results show that a significant weight savings has been achieved while all design criteria are met.

A straight cut tailpipe tip was empirically evaluated for the effect that the tip's orientation to a cross-wind had on the ability to reduce exhaust system backpressures associated with the purging of the combustion products. The straight across tip was attached to a vehicle at various angles of inclination to their axes while exhaust back pressure and performance readings were recorded. Testing indicated that there is a preferred orientation to reduce backpressure. Attempts to match on-vehicle data with wind tunnel data were met with partial success.

This paper presents the benefits of following a disciplined thermal management process during the design and development of Ford Light Truck engine cooling systems. The thermal management process described has evolved through the increased use of Computer Aided Engineering (CAE) tools. The primary CAE tool used is a numerical simulation technique within the field of Computational Fluid Dynamics (CFD). The paper discusses the need to establish a heat management team, develop a heat management model, construct a three dimensional CFD model to simulate the thermal environment of the engine cooling system, and presents CFD modeling examples of Ford Light Trucks with engine driven cooling fans.

Topology optimization is used for obtaining the best layout of vehicle structural components to achieve predetermined performance goals. Unlike the most common approach which uses the optimality criteria methods, the topology design problem is formulated as a general optimization problem and is solved by the mathematical programming method. One of the major advantages of this approach is its generality; thus it can solve various problems, e.g. multi-objective and multi-constraint problems. The MSC/NASTRAN finite element code is employed for response analyses. Two automotive examples including a simplified truck frame and a truck frame crossmember are presented.

A tunable stamped collector was developed to improve vehicle performance, drive-by noise and subjective noise quality, and reduced thermal stress concentrations. The stamped collector is located at the junction of the legs of the down pipe/catalytic converter assembly for a transverse mounted V-6 engine and acts to equalize the leg length of the down pipe, as well as provide acoustic tuning volume. This collector differs from most other methods to equalize leg lengths on transverse mounted engines in that it has a tuning chamber incorporated into the design itself, which allows for specific noise frequencies to be reduced. Performance characteristics were measured for a conventional down-pipe and the stamped collector using the following analysis techniques: Frequency analysis of tailpipe noise emissions. Drive-by noise emissions. Horsepower measurements using an engine dynamometer.

One of the major goals in the design of the new Ford Aeromax and Louisville heavy truck product line was to achieve competitive leadership in visibility. Market research found that visibility was an important issue to the heavy truck driver. Visibility is defined as both direct and indirect (i.e., the driver's ability to see with and without the use of supplemental vision devices such as mirrors) and both interior and exterior. The scope of this paper includes the work which was accomplished in evaluating direct and indirect exterior visibility and the resulting vehicle design which achieved Ford's leadership goals. Poor weather visibility and interior vision are beyond the scope of this paper. Polar Plots were the method of choice in the Aeromax/Louisville visibility studies. Industry acceptance of these techniques has been established in the recent approval of SAE J1750, “Evaluating the Truck Driver's Viewing Environment”.

One of the difficulties in predicting the structural behavior of vehicles such as the full size pickup trucks is the non-linearities involved during the course of the durability events. The current practice in durability and fatigue life prediction of vehicles is to conduct fatigue analysis on the structure using the measured road loads and estimate the fatigue incurred using the in-house and commercially available programs. In this paper the authors attempt to seek a different solution to the durability problem by conducting an upfront non-linear analysis. The results are then compared with the prediction by the fatigue life program in addition to the durability test results obtained on the early prototypes. To conduct the non-linear analysis ABAQUS FEA program is chosen for this investigation and for the linear analysis MSC/NASTRAN is utilized. Subsequently in-house fatigue program is used to predict the fatigue incurred.

The customer's perception of diesel sounds is receiving more attention since diesel engines are being used more frequently in recent years. This paper summarizes the results of a study investigating the sound quality of diesel idle sounds in eight vans and light trucks. Subjective evaluations were conducted both in the US and the UK so that a comparison could be made. Paired comparison of annoyance and semantic differential subjective evaluation techniques were used. Correlation analysis was applied to the subjective evaluation results to determine annoying characteristics. Subjective results indicated that most annoyance rankings were similar for both the US and UK participants, with some specific differences. Correlation of objective measures to annoyance indicated a high correlation to ISO 532B loudness, dBA and kurtosis in the 1.4 kHz to 4 kHz range (aimed at quantifying the impulsiveness perception).

Ford Motor Company has introduced its dedicated Natural Gas Vehicle (NGV) trucks as mid-year 1997 offerings to complement its dedicated Crown Victoria and bi-fuel Qualified Vehicle Modifier (QVM) product line-up. The 5.4L F-250 full-size pick-up truck and the 5.4L E-250/E-350 full-size vans are production vehicles maintaining Original Equipment Manufacturer (OEM) quality and warranty while complying with all applicable corporate, federal and state requirements. Both trucks are the first OEM vehicles to certify at the Super Ultra Low Emission Vehicle (SULEV) California medium-duty vehicle standard, the Federal Ultra Low Emission Vehicle (ULEV) standard, and the Federal Inherently Low Emission Vehicle (ILEV) emission standard. The use of natural gas (NG) as a vehicle fuel required unique hardware changes in the areas of fuel storage, fuel metering, and the emission control system.

The automotive industry has been increasingly researching and working on improving vehicle and passenger safety over the years. Following countries such as the United States and European Union, the Brazilian government has been publishing many resolutions with the objective of improving the safety of their fleet. With the publication of resolution 312 from CONTRAN (National Traffic Counsel), on April 3rd, 2009, the installation of ABS (Anti-lock Brake System) feature has become mandatory for all car and truck models to be sold in Brazil, following a staggered implementation starting on January 1st, 2010. The ABS system adds to the vehicle's current brake system, not allowing the wheels to lock during braking, which helps preserve the vehicle's stability and improve its safety, thus avoiding accidents. The technology, which is already available in a few car models, is not yet developed for the heavy trucks applications in this market.

A concept for combining the separate manual controls of a multiaxis system was explored and demonstrated on a Ford backhoe. The four axes of the backhoe system receive their command signal from a single 4 degree-of-freedom controller. The motion of the backhoe then “mimics” that of the controller, generating a followup signal to close the control loop. This control system provides simultaneous, coordinated control of all four axes in response to natural movements of the human operator.

The design requirements for the frame as a load carrying member are discussed in relationship to a highway truck and its basic vehicle package. The theoretical and experimental procedures are given in detail to demonstrate the techniques for frame design. The features of a method to laboratory test a frame with correlation to service miles is discussed.

Discussion of four factors pertinent to any overall ride evaluation. These factors are frame beaming, fifth wheel location, special body mountings, and variable loading conditions on tandem truck and tractor ride. The methodology for measuring the characteristics of these factors is reviewed and practical solutions for improved ride are given.