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The performance of radial lip seals in either vehicular or industrial applications is a significant factor in the perceived quality of products. Lubricant leakage is high on the list of customer complaints or dissatisfaction. Radial lip seal suppliers have been working closely with vehicle manufacturers to improve the performance of their products. Much progress has been made. Advances from this point will depend not only on improvements in sealing technology but also on improvements in the control of the entire sealing system.

It is extremely important to accurately depict photographs or video taken of a scene at night, when attempting to show how the subject scene appeared. It is widely understood that digital image sensors cannot capture the large dynamic range that can be seen by the human eye. Furthermore, todays commercially available printers, computer monitors, TV’s or other displays cannot reproduce the dynamic range that is captured by the digital cameras. Therefore, care must be taken when presenting a photograph or video while attempting to accurately depict a subject scene. However, there are many parameters that can be altered, while taking a photograph or video, to make a subject scene either too bright or too dark. Similarly, adjustments can be made to a printer or display to make the image appear either too bright or too dark. There have been several published papers and studies dealing with how to properly capture and calibrate photographs and video of a subject scene at night.

A Rankine cycle system with ethanol as the working fluid was developed to investigate the fuel economy benefit of recovering waste heat from a 10.8-liter heavy-duty (HD) truck diesel engine. Recovering rejected heat from a primary engine with a secondary bottoming cycle is a proven concept for improving the overall efficiency of the thermodynamic process. However, the application of waste heat recovery (WHR) technology to the HD diesel engine has proven to be challenging due to cost, complexity, packaging and control during transient operation. This paper discusses the methods and technical innovations required to achieve reliable high performance operation of the WHR system. The control techniques for maintaining optimum energy recovery while protecting the system components and working fluid are described. The experimental results are presented and demonstrate that 3-5% fuel saving is achievable by utilizing this technology.

Waste heat recovery (WHR) has been recognized as a promising technology to achieve the fuel economy and green house gas reduction goals for future heavy-duty (HD) truck diesel engines. A Rankine cycle system with ethanol as the working fluid was developed at AVL Powertrain Engineering, Inc. to investigate the fuel economy benefit from recovering waste heat from a 10.8L HD truck diesel engine. Thermodynamic analysis on this WHR system demonstrated that 5% fuel saving could be achievable. The fuel economy benefit can be further improved by optimizing the design of the WHR system components and through better utilization of the available engine waste heat. Although the WHR system was designed for a stand-alone system for the laboratory testing, all the heat exchangers were sized such that their heat transfer areas are equivalent to compact heat exchangers suitable for installation on a HD truck diesel engine.

A Rapid Duct Development and Diagnostic airflow simulation Tool (R3DT) has been developed that allows computational fluid dynamics (CFD) airflow simulations to be performed on complex three-dimensional (3D) Heating, Ventilation and Air Conditioning (HVAC) ducts quickly, easily and cost effectively. R3DT is a very automated approach to performing grid generation and CFD. It draws upon the strengths of the tools of ICEM CFD Engineering to create a fully tetrahedral mesh for complicated air duct geometries based on the original CAD data. It also uses FLUENT™ as the tetrahedral CFD solver. R3DT enables designers to make informed design decisions based on the predicted performance of their duct designs early in the development process, with the data still in CAD format. The concepts behind R3DT, as well as its application to a series of three-dimensional ducts with varying levels of geometrical complexity will be presented.

For most rolling element bearings used in practical applications, the permissible speed is defined as the bearing speed corresponding to a certain assumed limiting operating temperature in the bearing. Prediction of bearing permissible speed requires a thermal balance analysis considering 1) bearing heat generation (or torque) and 2) the heat dissipation of the bearing system, which is a function of ambient temperature, housing material and geometry and its heat transfer parameters. Recent results of running torque measurement of needle roller bearings and other types of roller bearings have been reviewed and compared with the well known Palmgren's prediction. The experimentally based formula for bearing power loss for needle bearings is used in the heat balance analysis for determining bearing reference and permissible speed. The calculated reference speed is compared with the DIN calculated reference speed using Palmgren's formula.

The premise of this paper is that the commonly heard proposals for regulating maximum gross loads of heavy commercial vehicles either do not reflect actual performance potential or are not practical to apply. A refinement of the gross weight per unit horsepower method is proposed in which the average horsepower available over the operating range of the engine would be substituted for any instantaneous value of power. This modification offers the advantage of reflecting the benefit of increases in the number of gear reduction steps and tends to compensate for differences in horsepower versus engine speed characteristics.

For about three decades, the Lambda ratio, i.e. the ratio of Ehd film thickness to the composite surface roughness has been used as an indicator for bearing lubrication as well as the basis for bearing load rating improvement. Although the film thickness and the Lambda ratio are relatively independent of load, the initiation of surface fatigue, or micropitting is load dependent. Furthermore, in the low Lambda region, the bearing surface fatigue and life ratio are more dependent on roughness than on film thickness. This paper reexamines the role of Lambda ratio and other parameters on bearing surface fatigue and bearing life ratio, by taking into consideration the severity of asperity interactions and microplastic deformation,

Assessing the dynamic performance of multilayer plates subjected to impulsive loading is of interest for identifying configurations that either absorb energy or transmit the energy in the transverse directions, thereby mitigating the through-thickness energy propagation. A reduced-order modeling approach is presented in this paper for rapidly evaluating the structural dynamic performance of various multilayer plate designs. The new approach is based on the reverberation matrix method (RMM) with the theory of generalized rays for fast analysis of the structural dynamic characteristics of multilayer plates. In the RMM model, the waves radiated from the dynamic load are reflected and refracted at each interface between layers, and the waves within each layer are transmitted with a phase lag. These two phenomena are represented by the global scattering matrix and the global phase matrix, respectively.

Four different off-highway truck hydraulic steering systems with varying complexity are presented. The reliability of each type of system is compared showing the effects of redundancy of components. The importance of system configuration is brought out to offset the adverse effects of a low reliability component. The advantages of a stored energy system in providing an emergency steering capability and in reducing the size of the pump are discussed.

This paper describes a crash detection system developed for use in automotive passive restraint applications. The system is unique in that the small, rugged module performs all of the functions necessary to determine when airbag deployment is required. Because it is designed to be mounted near the impact zone, the system is well suited to three difficult crash discrimination situations: front impacts in body-on-frame vehicles such as light trucks, side impacts in any automobile, and crash severity discrimination for future adaptive restraint systems.

Despite the best preventative measures, ruptured hoses, spills and leaks do occur with the use of all hydraulic equipment. Although these releases do not usually produce an RCRA (Resource Conservation and Recovery Act) regulated waste, they are often reportable events. Clean-up and subsequent administrative procedures involve additional costs, labor, and work delays. Concerns about these releases, especially when they involve Sandia National Laboratories, New Mexico (SNL) vehicles hauling waste on public roads, prompted their Fleet Services Department (FS) to seek an alternative to conventional petroleum-based hydraulic fluids. Since 1996, SNL has participated in a pilot program, along with the University of Northern Iowa (UNI) Ag-Based Industrial Lubricants (ABIL) Research Program and selected vehicle manufacturers, to field test in twenty of its vehicles, hydraulic fluid produced from soybean oil.

Nozzles tip Temperature (NTT) of an injector is a critical parameter for an engine as far as reliability of engine is concerned. It is required to ensure that the injectors operate under its operational limit because higher operating temperatures would result in enlargement of the nozzle spray tip, resulting in higher through flow, producing more undesirable power. This could result in failure of other components in the engine. In this paper we identify the various parameters that are critical for NTT and thereby predict the NTT by having the known input parameters. Response surface methodology and artificial neural network are used to identify the parameters, estimate the significance of each parameter and predict the NTT. Based on this analysis, even without the use of an instrumented injector NTT can be predicted at various working conditions of the vehicle on different terrains.

Future fuels for internal-combustion engines will be derived increasingly from solids such as coal. An alternative to processing coal into liquid fuels is the direct use of solid coal by reciprocating, internal -combustion engines. Specific applications which would be especially suitable for solid fueled engines consist of stationary power plants, marine propulsion systems, and railroad locomotives. Agricultural, construction and mining equipment are examples of other possible applications. The objectives of this study were to review past research on the development of solid coal fueled engines and, from this review, to identify major technical problems and current research needs. The objectives also included comparing the energy usage of several fuels. This comparison indicated a possible 25% energy advantage by directly using solid coal fuels as opposed to using synfuels.

Applications of active suspension control for both on-highway and off-highway vehicles are reviewed. Suspension design is evaluated in terms of ride vibration exposure and road/terrain handling. Active, semi-active, and slow-active suspension types are described in terms of their performance capabilities. Finally, numerous design concepts and their application to a wide range of ground vehicle types (i.e, truck, automotive, agricultural, and construction) are described.

Japan's truck production in 1962 accounted for 70% of total vehicles manufactured. Of this, 85% consisted of compacts and midget models for use by private enterprises and over congested narrow roads. Because of severe operating conditions on unpaved bumpy roads, large payloads require sturdier vehicles and higher ratios of power to weight than do those in other countries. Passenger bus transportation is expanding and extending service distances. Practically all large vehicles are diesel powered, but smaller ones are gasoline powered. The modernization of highways will bring larger and speedier models with more engine horsepower for longer distances.

Shot peening has been used for half a century to combat metal fatigue and stress corrosion cracking in highly loaded machines and structures. Despite its success as a “fix” for service problems, there has been a reluctance to specify shot peening in new designs. This has been based on a lack of confidence, the uniformity and repeatability of the process. Much of this has been overcome with the introduction of computer-enhanced peening equipment, which monitors and controls key process parameters. Computer enhanced shot peening and its equipment are reviewed with emphasis on what it does and does not do. The successful marriage of conventional and computer enhanced peening is used for critical aircraft, turbine, nuclear power plant, and truck transmissions and its use promises to grow.

This paper will review the current truck and bus steering column technology and marketplace in Europe. European specifications, norms and customer driven performance criteria are discussed. New technical solutions coming onto the market place are creating increasing diversity in techniques applied to steering column design and these are examined. An overview presentation of the Pailton Engineering past and current product and some of their development ideas looks at the two markets, truck and bus, separately. The concept of pedestal floor mounted and bulkhead mounted steering columns is considered. Mechanical clamping and air unclamping are explained and the use of electrically adjustable columns in trucks and buses is discussed. The concept of steering systems engineering to include the steering column as a vital integrated member in a steering system instead of a single stand alone item is discussed.