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Several computer programs are used by accident investigators to reconstruct motor vehicle accidents. These programs are seen as valuable tools by most investigators. However, it is also clear the programs are sometimes misused. This paper addresses five different types of computer programs used by accident investigators and discusses their proper and improper use. Most frequently, misuse is due to the lack of a thorough understanding of how the programs work. A series of recommendations is presented to help investigators properly use the programs.

The LM100 marine powerplant is a derivative of the T-58 turboshaft engine, the experience and maturity of which have been immediately valuable to the marine and industrial version. Some of the advantages of the LM100 discussed in this paper are its compactness, low specific fuel consumption, quick starting ability over a wide range of temperatures, and ability to withstand shock.

The application of aluminum armor plate for military vehicles has significantly increased during the past decade. Both US Army and Marine Corps place great emphasis on lighter weight, higher agility and fuel efficiency as well as improved survivability. This requires lighter armor which makes aluminum armor plate a major structural material. Recent US ARL investigations indicate that when properly designed, aluminum armor plate can indeed provide the required level of ballistic protection at lighter weight. Consequently, in the past few years, a number of new alloys and tempers have been added to military armor plate specifications. One tactical vehicle with aluminum hull i.e. MRAP RG-33 has already been deployed and is currently operating in both Afghanistan and Iraq. Also, one of the three selected JLTV designs uses aluminum hull.

The present status of temperature measurement using W/W-26% Re and W-5%, Re/W-26% Re is described. The availability of these materials is discussed with respect to quantity and quality. A discussion of field and fabrication problems and methods is presented, and precautions are outlined. Performance in a variety of applications of bare wire and swaged construction thermocouples is evaluated and data are presented. The present status of these thermocouple materials with respect to availability, calibration control, fabrication of sheathed constructions, application problems, and emf stability after high temperature service are reviewed.

To reduce noise in a HVAC system for railway application the usage of micro-perforated panels (MPP) is proposed. MPPs offer some favorable characteristics, like robustness and durability in harsh environments and the possibility to optimize absorption in desired frequency bands. The underlying acoustic mechanism can be modelled via an equivalent fluid in accordance with the Johnson-Champoux-Allard (JCA) approach, treating the MPPs as a porous material with rigid frame. This allows to conduct the necessary acoustic pre-evaluation in complex HVAC application scenarios in order for the MPPs to substitute the commonly used foam and fibrous absorber materials.

The newest class of synthetic rubbers, the ethylenepropylene rubbers, abbreviated to EPR, offer improved ozone and oxidation resistance which it is believed will show advantages in many automotive weathersealing applications at costs equal or less than currently used rubbers. Other applications foreseen for these rubbers are sponge trim padding, armrest pads, and windlace, electrical wiring, hose, floor mats, grommets, and bumpers.

Securing the desired strength and durability characteristics of suspension components is one of the most important topics in the development of commercial vehicles because these components undergo multiaxial variable amplitude loading. Leaf springs are essential for the suspension systems of trucks and they are considered as security relevant components in the product development phase. In order to guide the engineers in the design and testing department, a simulation method is developed as explained by Bakir et al. in a recently published SAE paper [1]. The main aim of the present study is to illustrate the validation of this simulation method for the durability of leaf springs based on the results from testing and measurements. In order to verify this CAE Method, the calculated stresses on the leaf springs are compared with the results of strain gage measurements and the fatigue failures of leaf springs are correlated with the calculated damage values.

This study introduces a system which integrates a mechanical motion capture system into computer-aided ergonomics assessment. The study focuses on the application of the system on industrial ergonomics studies and evaluation of system's over-time reliability and criteria-related validity in assessing ergonomics risks. Two lifting jobs were analyzed using this system in the real industrial environment. By taking the manual measurement as the baseline criteria, the validity of the system was assessed. The system demonstrated the capability in efficiency and accuracy. Also, participants were invited to perform two lifting tasks in a well-calibrated lab environment in different time. By comparing the ergonomic assessment results between different trials, the system over-time reliability was assessed. The high correlation of ergonomics result between trials demonstrated good over-time reliability.

Hydrogen is seen as a promising energy carrier for a future mobility scenario. Applied as fuel in IC engines with internal mixture formation, hydrogen opens up new vistas for the layout of the combustion system. The 3D CFD simulation of internal mixture formation as well as combustion helps to understand the complex in-cylinder processes and provides a powerful tool to optimize the engine's working cycle. The performance of standard simulation models for mixture formation as well as the performance of a user-defined combustion model applied in a commercial CFD-code is discussed within this article. The 3D CFD simulations are validated with measurements obtained from a thermodynamic and from an optical research engine respectively.

Synchronized pulsed flushing is described as a method for controlling wear on electrodes during the EDM process, which uses electrical energy to remove material in machining. Background is provided on EDM phenomena. The attributes of wear are specified, and the method of synchronized pulsed flushing is contrasted with continuous flushing.

In many automotive highway/off-highway engine cooling applications the fan has to provide a fairly large pressure rise and operate with a large gap between the tip of the blade and the shroud surface (tip clearance). This can pose difficult design challenges. This paper presents a design process coupling 3D inverse design with a Multi Objective Genetic Algorithm (MOGA) for an axial cooling fan. The aim is to reduce the leakage loss and profile losses to improve performance. The inverse design method parameterizes the 3D shape of the axial fan with a reduced number of design parameters allowing a larger exploration of the design space in the optimization process. The methodology is applied to the design of a highway truck engine cooling fan with a tip gap of 8% of blade height. Two designs from the optimization are analyzed in detail using 3D Computational Fluid Dynamic (CFD) simulations, confirming that the design optimized for minimizing leakage losses meets the design specification.

When a vehicle with protruding wheel studs makes contact with another vehicle or object in a sideswipe configuration, the tire sidewall, rim and wheel studs of that vehicle can deposit distinct geometrical damage patterns onto the surfaces it contacts. Prior research has demonstrated how relative speeds between the two vehicles or surfaces can be calculated through analysis of the distinct contact patterns. This paper presents a methodology for performing this analysis by visually modeling the interaction between wheel studs and various surfaces, and presents a method for automating the calculations of relative speed between vehicles. This methodology also augments prior research by demonstrating how the visual modeling and simulation of the wheel stud contact can extend to almost any surface interaction that may not have any previous prior published tests, or test methods that would be difficult to setup in real life.

Use of 3D-CAD system has reduced the development period required for new automobiles. IHI has developed advanced 3D-CAD system for automotive turbochargers, which satisfies requirements for digital mock-up development. The new system can reduce the development time by about 30% compared with the 2D-CAD system. The design quality was greatly improved by the 3D-CAD system, particularly the 3D models produced by the system, which can draw more accurate fluid passages such as scroll casing, or stress analysis of 3D data based on FEM. 3D-CAD data are suitable for use in manufacturing processes and product aftercare services, allowing centralization of activities for development, production, and application to vehicle engines.

This paper shows extracts from the development process of a lean-burn gaseous fuelled engine for combined heat and power generation. The aim was to optimize the mixture formation, the charge motion and the combustion of an existing multi-cylinder engine. Therefore, experimental investigations on a single cylinder research engine and numerical simulations based on 3-dimensional CFD methods were carried out. The use of CFD methods for the optimization of the engine required intensive development efforts in the field of combustion simulation. In particular, the combustion model developed by Magnussen and Hjertager [1] was modified. Through comparison with the PDF model and results of the engine process calculation, the suitability of this modified combustion model was shown. In addition, a knock model was also developed and implemented in the CFD code in order to determine the knock tendency of different engine concepts.

Increasing oil prices and emission legislation have forced car manufacturers and suppliers to investigate new methods and technologies to improve the efficiency of current spark ignition engines. In order to follow these trends and to yield a contribution in the development of modern combustion concepts, spark plugs with improved ignition performance are required. Reliable ignition and inflammation in operating points employing stratified and lean air/fuel charge is thereby a challenging task. In this study we are using a full 3D model of the engine which is offering a possibility to conduct a virtual replacement of the spark plug. With this modeling concept we are able to investigate the influence of different spark plug designs on the ignitability of the air/fuel mixture at the ignition time.

During the evolution of Hybrid vehicles as well as electrical vehicles the need for an additional Voltage level was defined for the utilization of high power loads like electrical compressors, electrical heaters as well as power steering and electrical pumps. The main systems benefit is the generation of approximately 12 kW electrical power by a traditional belt driven Generator. This allows boost function for acceleration and recuperation for mild hybrid vehicles with the target to reduce up to 15% CO2 by keeping the traditional thermal based engines. Delphi has developed systems and components that meet the special 48 Volt related electrical requirements on arcing, hot plugging and corrosion. Our benefit is the long term expertise within the total system know how and the derived technical specification and needs.

Vehicle OEM’s for MHD applications are facing significant challenges in meeting the stringent 2027 low-NOx and GHG emissions regulations. To meet such challenges, advanced engine and aftertreatment technologies along with powertrain electrification are being applied to achieve robust solutions. FEV has previously conducted model-based assessments to show the potential of 48V engine and aftertreatment technologies to simultaneously meet GHG and low NOx emission standards. This study focuses on evaluating the full potential of 48V electrification technology through addition of 48V P3 hybrid system to the previously developed 48V advanced engine and aftertreatment technology package. Previously, a model-based approach was utilized for selection and sizing of a 48V system-enabled engine and aftertreatment package for class 6-7 MHD application.

A highly ductile TRIP steel sheet has been developed and put into practical use to achieve weight savings in automotive Bodies-in-White. During deformation, TRIP steels experience a strain-induced transformation of retained austenite to hard martensite. This TRIP-effect increases the strength of the material and improves the formability by distributing strain over a larger area. In comparison to conventional high strength steel (HSS), TRIP steels have a superior balance between strength and ductility. The TRIP steels newly put into practical use at 590MPa and 780 MPa strength levels had equivalent formability to conventional HSS at the 440MPa and 590 MPa levels, respectively. Also it achieved equivalent coating quality, paintability and spot weldability to conventional HSS. Consequently, it was found that these TRIP steels can feasibly be applied to a wide variety of vehicle parts.

There are strong demands for vehicle weight reductions so as to improve fuel economy. At the same time, it is also necessary to ensure crash safety. One effective measure for accomplishing such both requirements conflicting each other is to apply advanced high strength steel (AHSS) of 780 MPa grade or higher to the vehicle body. On the other hand, higher strength steels generally tend to display lower elongation causing formability deterioration. Nissan Motor Corporation have jointly developed with steel manufacturers a new 980 MPa grade AHSS with high formability with the aim of substituting it for the currently used 590 MPa grade high-tensile steel. Several application technologies have been developed through the verifications such as formability, resistance spot weldability, crashworthiness, and delayed fracture.

Multiple injection strategies have been revealed as an efficient means to reduce diesel engine NOx and soot emissions simultaneously, while maintaining or improving its thermal efficiency. Empirical soot models widely adopted in engine simulations have not been adequately validated to predict soot formation with multiple injections. In this work, a multiple-step phenomenological (MSP) soot model that includes particle inception, surface growth, oxidation, and particle coagulation was revised to better describe the physical processes of soot formation in diesel combustion. It was found that the revised MSP model successfully reproduces measured soot emission dependence on the start-of-injection timing, while the two-step empirical and the original MSP soot models were less accurate. The revised MSP model also predicted reasonable soot and intermediate species spatial profiles within the combustion chamber.