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Do older light trucks, often with second (and subsequent) owners, present a higher risk to either their own occupants or to other road users? And is the safety record for newer trucks better or worse than the record for their older counterparts? To answer these questions, fatalities in crashes involving at least one light truck were examined using the Fatal Analysis Reporting System (FARS). Fatality rates for both occupants of the light truck and for other road users (occupants of other motor vehicles, pedestrians, etc.) in these crashes were computed, based both on the number of registered vehicles and on the vehicle miles of travel. Two trends in these fatality rates are observed. First, as light trucks age, a consistent decline is found in risk both to their own occupants and to other road users. Second, a distinct decrease is found in road user risk for newer light trucks compared to older light trucks when they were new, both for their own occupants and for other road users.

Equal channel angular extrusion (ECAE) is a promising novel technique for inducing microstructural refinement in polycrystalline materials by imposing large plastic strains. In this paper, several topics on ECAE of materials for potential automotive applications are briefly addressed. The reported results include 1) microstructural evolution and mechanical behavior of ECAE processed copper, 2) welding behavior of ECAE and other copper alloy spot welding electrodes, 3) microstructural changes associated with breaking up and homogeneously distributing second phase particles in aluminum alloys, and 4) beneficial effects of large deformations on the strength of rapidly solidified stainless steels. These results demonstrate the potential of ECAE for producing improved alloys for automotive applications, as well as indicate technological challenges and directions of future work.

This paper presents the development of a new top-of-rail lubrication system that uses precise computer control and an environmentally friendly lubricant to produce significant energy savings and other economic benefits for railroads. The system and lubricant evolved over a period of five years from analytical solution, design and prototyping, to production, field-testing and demonstration. Based on extensive field-testing, energy savings of 15% and a 2% increase in productivity can be achieved by railroads using this system.

The DOE Office of Heavy Vehicle Technologies (OHVT) focuses its research and development efforts on technologies that are critical to the needs of the U.S. heavy vehicle industry because of the importance of trucks and other heavy vehicles to economic activity and growth. A strategy has been crafted in collaboration with OHVT's industry customers (truck and engine manufacturers, fuel developers/producers, and their suppliers, truck users, and others) that will enable future energy demand of the U.S. heavy vehicle industry to be met, with reduced dependence on imported oil, and without adverse environmental effects. This strategy is centered on the technical strengths of the advanced compression-ignition (Diesel cycle) engine and its potential to use fuels from alternative feedstocks, and to reduce exhaust emissions to very low levels.

Thermal management is a cross-cutting technology that directly or indirectly affects engine performance, fuel economy, safety and reliability, aerodynamics, driver/passenger comfort, materials selection, emissions, maintenance, and component life. This review paper provides an assessment of thermal management for large on-highway trucks, particularly as it impacts these features. Observations based on a review of the state of the art for thermal management for over-the-road trucks are highlighted and commented on. Trends in the large truck industry, pertinent engine/truck design and performance objectives, and the implications of these relative to thermal management are presented. Finally, new thermal management concepts for high-efficiency vehicles are described.

One scenario for reducing engine out NOx in a spark ignition engine is to introduce small amounts of supplemental hydrogen to the combustion process. The supplemental hydrogen enables a gasoline engine to run lean where NOx emissions are significantly reduced and engine efficiency is increased relative to stoichiometric operation. This paper reports on a mass and energy balance model that has been developed to evaluate the overall system efficiencies of a thermal reformer-heat exchanger system capable of delivering hydrogen to the air intake of a gasoline engine. The mass and energy balance model is utilized to evaluate the conditions where energy losses associated with fuel reformation may be offset by increases in engine efficiencies.

This paper describes research and development for reducing the aerodynamic drag of heavy vehicles by demonstrating new approaches for the numerical simulation and analysis of aerodynamic flow. In addition, greater use of newly developed computational tools holds promise for reducing the number of prototype tests, for cutting manufacturing costs, and for reducing overall time to market. Experimental verification and validation of new computational fluid dynamics methods are also an important part of this approach. Experiments on a model of an integrated tractor-trailer are underway at NASA Ames Research Center and the University of Southern California. Companion computer simulations are being performed by Sandia National Laboratories, Lawrence Livermore National Laboratory, and California Institute of Technology using state-of- the-art techniques, with the intention of implementing more complex methods in the future.

Even with the rapidly evolving computational tools available today, suspension design remains very much a black art. This is especially true with respect to road cars because there are so many competing design objectives. In a racecar some of these objectives may be neglected. Even still, just concentrating on maximizing road-holding capability remains a formidable task. This paper outlines a procedure for establishing suspension parameters, and includes a computational example that entails spring, damper, and anti-roll bar specification. The procedure is unique in that it not only covers the prerequisite vehicle dynamic equations, but also outlines the process that sequences the design evolution. The racecar design covered in the example is typical of a growing number of small open wheel formula racecars, built specifically for American autocrossing and British hillclimbs.

Electron beam (EB) welding process is characterized by an extremely high power density that is capable of producing weld seams which are considerably deeper than width. Unlike other welding process, heat of EB welding is provided by the kinetic energy of electrons. This paper presents a computational model for the numerical prediction of microstructure and residual stress resulting from EB welding process. Energy input is modeled as a step function within the fusion zone. The predicted values from finite element simulation of the EB welding process agree well with the experimentally measured values. The present model is used to study an axial weld failure problem.

Contemporary principles of management apply to the aviation maintenance manager as much as they apply to manufacturing, marketing, and other kinds of managers. Maintenance managers plan, organize, lead, and control, all in the context of complying with urgent business imperatives. This paper discusses aviation maintenance management imperatives in hopes of enhancing the professionalism of the field’s culture with regard to airworthiness and safety.

This paper will describe a patent-pending approach of using a vapor compression system to also provide a forced two-phase indirect heat transfer loop. This system can be configured with water boiler peak cooling thermal control hardware to avoid the high ambient temperatures associated with supersonic low altitude flight. Due to the very short duration of this high ambient condition, water boiler transient cooling techniques have potential. The water boiler can also be used for ground based cooling when flight-line ground cooling carts are unavailable. The use of a PID controller to accurately control the cold plate temperatures when used with a solenoid activated by-pass circuit will be described.

Recently, aerodynamic noise which originates in the flow of the body surroundings is actualized as a main cause of an automobile interior noise when running at high speed, because engine, power train and tire noise have been greatly decreased. Along with it, the measurement technology for the phenomenon elucidation and the evaluation has been demanded to decrease aerodynamic noise. In this paper, typical measurement examples of aerodynamic noise are introduced. These measurement technologies can be classified, and arranged to four types of measurements, which are flow, external noise, transmission psth and interior noise. This paper presents how the advancement of these measurement technologies has contributed to the aerodynamic noise elucidation. Moreover, the latest evaluation method of aerodynamic noise and the trend in the future to the demand of customer's many topics are introduced.

In the search for clean and efficient power, PEM fuel cells have been identified as the technology that can meet our future needs for transport applications. Hydrogen-powered PEM fuel cell vehicles are perceived to give the ultimate advantage, but the complications involved with hydrogen storage and refuelling, as well as the lack of infrastructure call for a different solution. In the near term, this is almost certain to be the on-board generation of hydrogen from a readily available fuel. At Johnson Matthey, a novel modular reformer (HotSpot™) has been developed for methanol, and has been demonstrated to have many of the qualities that are required for automotive applications. Auxiliary technologies for CO removal (Demonox) and aftertreatment have also been developed, and integrated with the reformer to form 20 kWe processor, which is currently undergoing brass-board testing.

The 100-year saga of The Timken Company is a testament to the enduring power of innovation, grit and periodic self-renewal. It is the story of a quest to solve one of industry's oldest, most limiting and expensive challenges: friction. Today's Timken combines materials science with bearing technology to produce products that range from a half ounce to nine tons and help power and control applications that span disk drives, drilling rigs, dental drills and rolling mills. Today's automotive bearing is less than half the size and 90 percent lighter than its ancestor - and carries twice the load.

The use of electrohydraulic actuators in engine control applications has the potential to improve engine performance and fuel economy. Digital latching valves open and shut extremely quickly. Furthermore, by using residual magnetism, the valves remain latched in the open or closed position and only use energy when transitioning between positions. In this paper, the control issues involved with using latching valves for closed loop position control of a piston-cylinder actuator are examined. The valve design, system models and alternative controller designs are presented. The first control design is based on minimizing a cost function measure of errors and control energy usage, which quantifies a trade-off between tracking accuracy, resolution and control energy usage. The second design, which is called inner sample modulation of the valve, is based on calculating the appropriate control action as some fraction of the sampling time.

A unified tire model with non-isotropy of friction and arbitrary contact pressure distribution is presented as a foundation to study the key features of a reasonable expression of tire shear force and alignment torque under combined slip conditions. The effects of contact pressure distribution on tire mechanical characteristics are analyzed. A unified semi-empirical tire model with convenience in dynamics simulation is recommended. For determining the model parameters, a series of simple expressions that satisfy the boundary conditions are proposed and a new global fitting method for tire data processing is employed. Based on the improved semi empirical model, the USPA software is developed. This software reduces the modeling time from the tire data to a practical tire model and allows various tire characteristics analyses. Some experimental validations are shown.

This paper evaluates several durability tire models using Virtual Tire Testing (VTT) strategy. VTT conducts tire testing (simulation) using LS–DYNA based on a Virtual Tire which is built by 3–D finite element mesh. VTT is repeatable and could do special tire tests which can't be done using normal tire testing bench. A brief review is given on durability tire models and several typical tire models are selected for this study. All the necessary parameters for establishing the analytical tire models are extracted from the Virtual Tire. Quarter vehicle model is used to simulate the vehicle vertical vibration. The comments of those analytical tire models are given based on their performance vs. VTT.

Carbon black has contributed a series of important performance enhancements to tires, ranging from increased wet and dry traction to decreased rolling resistance. This paper briefly discusses the roles that carbon black plays in tire manufacturing, then moves broadly through a decade-by-decade list of key technical milestones for carbon-black formulation and applications. The paper ends with a discussion of 2 new technologies for tire fillers: carbon-silica dual-phase, fillers for rubber, and chemically modified carbon blacks, a promising breakthrough that confers controlled reactivity to carbon-black filler. Overall, the paper demonstrates that carbon black has played a leading role in enhancing tire life and performance.

This paper describes the design development of a new steel wheel which utilizes spokes to provide either weight or strength benefits over a conventional dish center wheel. The spokes are designed to be deep along the axis of the wheel and thin in the plan view of the wheel to provide improved strength and fatigue resistance. This unique patented approach uses spoke pairs to help achieve those advantages. Wheel designs utilizing this type of spoke are analyzed using classical methods as well as the finite element method. Results of the traditional analyses are presented in the form of maximum apparent stress calculations for wheels of various sizes. Corresponding finite element results are presented in the form of stress distributions plotted on solid model representations of wheels with magnitudes and locations of stresses shown.