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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.

Bench reactor experiments were carried out to investigate the effects of operating temperature, precious metal loading, space velocity, and air-fuel (A/F) ratio on the performance of palladium (Pd) catalysts under simulated natural gas vehicle (NGV) exhaust conditions. The performance of these catalysts under simulated gasoline vehicle (GV) conditions was also investigated. In the case of simulated NGV exhaust, where methane was used as the prototypical hydrocarbon (HC) species, peak three-way conversion was obtained under richer conditions than required with simulated GV exhaust (propane and propene HC species). Moreover, the hydrocarbon efficiency of the catalyst under simulated NGV exhaust conditions was more sensitive to both A/F ratio and perturbations in A/F ratio than the HC efficiency under GV exhaust conditions.

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.

Frequency domain testing has had limited use in the past for durability evaluations of automotive components. Recent advances and new perspectives now make it a viable option. Using frequency domain testing for components, test times can be greatly reduced, resulting in considerable savings of time, money, and resources. Quality can be built into the component, thus making real-time subsystem and full vehicle testing and development more meaningful. Time domain testing historically started with block cycle histogram tests. Improved capabilities of computers, controllers, math procedures, and algorithms have led to real time simulation in the laboratory. Real time simulation is a time domain technique for duplicating real world environments using computer controlled multi-axial load inputs. It contains all phase information as in the recorded proving ground data. However, normal equipment limitations prevent the operation at higher frequencies.

Dimensional variability must be managed. Assembly plant installation processes which require operator adjustment result in random, unpredictable variability. On the other hand, processes which use locators and quality controlled components eliminate operator adjustments. This results in managed variability with repeatable and dimensionally consistent end products. The 1994½ Windstar mini-van incorporated locators with a detailed component quality control plan and then went one step further. Dimensional variability was managed and verified during the design process to ensure that every vehicle produced would meet customer quality standards. To verify that the Windstar would achieve the customer quality standards, by design, a full vehicle dimensional variability model was developed. The body structure, interior trim, major instrument panel components, suspension, steering and various subsystems were modeled.

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.

The salt spray test has been an industry wide standard corrosion test since its conception in 1914. A literary review of its history shows that it has· always been thought of as inconsistent and unreliable but, for a variety of reasons, has continued to be used. A study of more than 55 salt spray cabinets was performed using a controlled lot of parts and questionnaires on cabinet operation. Although the tested parts varied from mildly corroded to extremely rusted no factor could be found to account for the differences. Although the test has its uses it should be studied by an industry formed committee which should make recommendations as to further standardization and corrections to the test. A lengthy chronological bibliography aids the reader in further study and reference.

A front suspension laboratory test procedure was developed to reproduce time-correlated fatigue damaging events from a light truck road durability test. Subsequently, the performance of front suspension systems for the GMT 400 light truck program were evaluated in terms of customer reliability. Both prototype and pilot testing, as well as computer modeling, were used in the evaluation.

During the development of a new friction material, besides the interface between lining/drum is also fundamental take in account all aspects involving the attachment of the linings on the brake shoes. This paper presents an optimization approach to the development and manufacturing parameters of brake linings, applied on medium and heavy duty commercial vehicles, aiming to assure the correct specification of the riveted joint clamp forces. These evaluations were conducted based on the quality tools documents and the theoretical aspects of the product usage as well as the modeling of key elements of the referred mechanism throughout various known applications. A calculation methodology was developed based on brake geometry, its generated forces and braking reactions required for each vehicle family.