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The sources of data on materials used in the automotive industry are reviewed and their shortcomings discussed including limited availability, obsolescence, limited coverage of materials, limited information on materials covered, and lack of information on the variability of properties. The way that data from presently available “hard copy” data sources are presently used in automotive design is outlined. Several of the small number of currently available computerized materials data bases are briefly described. Finally, anticipated benefits from the use of greatly expanded computerized systems are enumerated. These include the use of “artificial intelligence” for the selection of materials, making very extensive information on many materials available to all designers on the screens of their terminals, allowing instantaneous dissemination of warnings of materials problems, and serving as a repository of engineering know-how for transfer from one generation of engineers to the next.

TRUCKS, tanks, and engines are of no use to an army if they are delivered to the battlefield with parts broken or badly corroded. The problems involved in protecting these parts from corrosion during storage and shipment are discussed thoroughly by the authors, who also explain the best methods and materials to use in protecting different types of parts under the extremes of temperature, humidity, and corrosive atmosphere likely to be encountered.

Providing adequate level of comfort is the main objective of an HVAC. This kind of information is not very useful at the end of a study and also is very expensive to obtain if only an experimental approach is used. In fact, the analysis of comfort problem is the right place for a model. The paper will concern the development of a in cab thermal comfort numerical model. The first part of the development is only achieved for the winter outside conditions. The model is developed in order to predict the local thermal sensations of the car driver according to the thermal conditions provided by the heating system. A lot of experiments have been lead in the VALEO wind tunnel to complete and validate the model. The development perspectives concern the summer outside conditions. This study supported by VALEO Climate Control and PSA PEUGEOT CITROEN, has been performed by the Laboratory LESETH (University of Toulouse).

The National Renewable Energy Laboratory’s (NREL’s) CoolSim MATLAB/Simulink modeling framework was expanded by including a newly developed coolant loop solution method aimed at reducing the simulation effort for complex thermal management systems. The new approach does not require the user to identify specific coolant loops and their flow. The user only needs to connect the fluid network elements in a manner consistent with the desired schematic. Using the new solution method, a model of NREL's advanced combined coolant loop system for electric vehicles was created that reflected the test system architecture. This system was built using components provided by MAHLE Inc. and included both air conditioning and heat pump modes. Validation with test bench data and verification with the previous solution method were performed for 10 operating points spanning a range of ambient temperatures between -2°C and 43°C.

There is insufficient time within a single technical elective to learn principles of internal combustion engine operation as well as specialized simulation tools such as GT Suite or Kiva. A number of authors have recognized this constraint, and they have structured their internal combustion engine text around use of programming languages such as FORTRAN, C++, and MATLAB®. This paper reports on how the capabilities of MATLAB® have been synergized with learning activities and homework assignments to set the stage for a successful final engine simulation project. The MATLAB® code involved in this effort can accept basic input parameters such as bore, stroke, compression ratio, spark advance, throttle position, RPM, air/fuel equivalence ratio, and volumetric efficiency. The code returns output power and torque using the Wiebe function and bulk temperature. The model uses a two-zone heat release model to predict power, torque, brake specific fuel consumption, and volumetric emissions.

This white paper explains the benefits of the Model-Based Design (MBD) approach and Object-Oriented Technology (OOT) that DO-178C provides. It also specifically focuses on the usage of Models and COTS Qualifiable tools that automate or facilitate the verification and validation of avionics applications constructed from Models in order to ensure that there is no unintended function. Software running in Aircraft cockpits has dramatically increased in complexity since DO-178B's revision in 1992. Furthermore, over the past 20 years, software development methods have made significant leaps forward and DO-178B has begun to show its age with respect to the new technology introduced to facilitate software development. This year the newly revamped DO-178C standard sets the certification process record straight by embracing modern technology.

For better power output and fuel economy of a four stroke cycle ignition engine, the ignition timing should preferably be set to the minimum spark advance for best torque (MBT). It is found that when the ignition timing is set MBT, the crank angle of the maximum combustion pressure (θpmax) usually lies between 12 and 14 deg after top dead center (ATDC) regardless of any engine specifications or operating factors. Therefore, the ignition timing can be controlled to be MBT by using the θpmax. This paper describes the relationship between the θpmax and MBT by both experimental results and numerical calculations, and MBT control system utilizing θpmax. And the test results by using this system are also described.

Making use of spark-plug-washer type cylinder pressure sensors and a high-performance 16-bit microprocessor, the authors have developed a new control system (Nissan ECCS) of ignition timing for gasoline engine. Use of this system results in effective control, enabling each engine to deliver maximum torque and minimum fuel consumption at all conditions, regardless of changes in environmental conditions, etc.

Maximum Brake Torque (MBT) timing for an internal combustion engine is the minimum advance of spark timing for best torque. Traditionally, MBT timing is an open loop feedforward control whose values are experimentally determined by conducting spark sweeps at different speed, load points and at different environmental operating conditions. Almost every calibration point needs a spark sweep to see if the engine can be operated at the MBT timing condition. If not, a certain degree of safety margin is needed to avoid pre-ignition or knock during engine operation. Open-loop spark mapping usually requires a tremendous amount of effort and time to achieve a satisfactory calibration. This paper shows that MBT timing can be achieved by regulating a composite feedback measure derived from the in-cylinder ionization signal referenced to a top dead center crank angle position. A PI (proportional and integral) controller is used to illustrate closed-loop control of MBT timing.

MBT timing for an internal combustion engine is also called minimum spark timing for best torque or the spark timing for maximum brake torque. Unless engine spark timing is limited by engine knock or emission requirements at a certain operational condition, there exists an MBT timing that yields the maximum work for a given air-to-fuel mixture. Traditionally, MBT timing for a particular engine is determined by conducting a spark sweep process that requires a substantial amount of time to obtain an MBT calibration. Recently, on-line MBT timing detection schemes have been proposed based upon cylinder pressure or ionization signals using peak cylinder pressure location, 50 percent fuel mass fraction burn location, pressure ratio, and so on. Because these criteria are solely based upon data correlation and observation, both of them may change at different engine operational conditions. Therefore, calibration is still required for each MBT detection scheme.