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IN TODAYS' TECHNOLOGICAL WORK, the evaluation of electrical connectors for the electronic industry are many times based on antiquated specifications and unrealistic performance requirements. It is the intent of this paper to explain a new method of connector evaluation. This method is based on the determination of theoretical design, permanent set, cyclic and normal force characteristics which are evaluated as to their significance as independent entities and their interrelationships. This data can be supplemented by normal force - contact resistance - separation force correlations. Proper interpretation of this data can lead to realistic specifications and performance requirements. The data can also be used for the purpose of trouble shooting as well as an important guide for further design programs.

High speed knock leads in particular circumstances to serious damage. Several mechanisms may be the source of deteriorations: preignition usually due to the presence of deposits. overheating ruining immediatly the engine when a “runaway knock” occurs. gradual decay of the combustion chamber depending on the design of the chamber and on the quality of materials. Analysing the temperature of the exhaust gases and establishing special testing techniques make possible the quantitative study of knock damage. The paper gives examples of matching of fuels and engines at knock damage limit.

Many approaches have been taken to determine the burning velocity in internal combustion engines. Experimentally, the burning velocity has been determined in optically accessible gasoline engines by tracking the propagation of the flame front from the spark plug to the end of the combustion chamber. These experiments are costly as they require special imaging techniques and major modifications in the engine structure. Another approach to determine the burning velocity is from 3D CFD simulation models. These models require basic information about the mechanisms of combustion which are not available for distillate fuels in addition to many assumptions that have to be made to determine the burning velocity. Such models take long periods of computational time for execution and have to be calibrated and validated through experimentation.

A new jet fuel filtration monitoring system and technique is described which provides an assessment of the current performance and signals the end of the useful life of filter/separator and clay treatment elements. The need for such a system has long been recognized by the aircraft fueling industry to indicate when surface active agent type contaminants in jet fuels are no longer efficiently removed by clay treatment and/or interfere with the water coalescence function of the filter separator. The system, which has been developed and called a Filter Sidestream Sensor, operates on a sidestream with dynamic similarity to the main filter separator or clay vessel. It has been designed to provide a cumulative history of all factors which affect filter performance. Correlations between Filter Sidestream Sensor and main filter performance are provided together with data on the effects of surfactants–both natural and additive types, and the role played by water in coalescence deactivation.

A new computerized method using a thin, flexible sensor to measure stress distribution during loading and unloading of gaskets is disclosed. Stress measurement is achieved by a change in the sensor's electrical resistance as a function of load. Each sensor has many electrical pressure responsive contact points that give a map of stress. The unloading of a gasket due to hydrostatic end forces, thermal motions, and external loads can be observed and measured without modifying the flange environment. Use of this new technology permits better and faster gasket and flange design optimization. Monitoring of gasket stress during unit operation is also possible in some cases. The system uses a personal computer operating specially developed graphics software. It provides visual two and three dimensional dynamic stress distribution representations as well as total compressive force, on the sensor, in real time.

A comprehensive treatment of a new technique to measure vehicle aerodynamic response under side wind conditions is presented. In opposition to the traditional measurement technique of yawing the vehicle by rotating the turntable, the flow itself is continuously deflected by the Pininfarina Turbulence Generation System (TGS), while keeping still the vehicle under investigation. By using this new technique it is possible to assess the dynamic behavior of vehicles, with particular regard to side forces and yawing moment, in more realistic unsteady conditions opposed to the static setup of traditional measurements. In the first part of this work, the unsteady flow, generated by the TGS, is characterized both by means of 4-hole Cobra probe and stereo PIV measurements in empty and non-empty wind tunnel configuration. Some data acquired on the road will also be shown and compared with wind tunnel measurements.

This paper describes a new bipolar IC technology and innovative circuit design applied to produce a new generation of audio power amplifier ICs for car radio. A reduced external component count, better protection and the absence of turn on/off noise are the most significant characteristics of the new design.

Anybody knows that contamination in oil is always harmful to hydraulic and lubricating systems. Contaminants inevitably exist in the oils of hydraulic and lubrication systems and cause tribological problems. In order to prevent such tribological problems due to contaminants, various oil cleaners have been developed and applied to hydraulic and lubricating systems. They have greatly contributed to improving the reliability of the systems. Since sophisticated hydraulic systems with proportional valves or servo valves, which are sensitive to oil contamination, became popular, fine filters like 3 micron or 1 micron are additionally used. However contamination problems have been revived. The authors have investigated the causes of hydraulic and lubricating problems and found that polymerized oil oxidation products were as harmful as solid particles. They are of molecular size and cannot be removed by mechanical filtration.

A new technology for temperature sensors has been developed. The sensors are extremely rugged, capable of withstanding the most rigorous environments, and they are expected to result in very inexpensive product manufacture. This paper discusses the evolution of the design of metal core hybrid substrates and the principles of construction of a temperature sensor as a hybrid circuit on a metal core substrate. Sensor performance characteristics and cost are also explored. A discussion of the linearity of voltage response to temperature is included, and data are presented on the performance of the sensor in various environments. The paper concludes that the new sensor is suitable for operation in all environments found in automotive applications, and that its range is sufficient to accommodate all of the control functions currently found in the literature.

A new test bench has been set up and equipped in order to analyze the air mean motion and turbulence quantities in the combustion system of an automotive diesel engine with one helicoidal intake duct and a conical type in-piston bowl. A sophisticated HWA technique employing single- and dual-sensor probes was applied to the in-cylinder flow investigation under motored conditions. The anemometric probe was also operated as a thermometric sensor. An analytical-numerical procedure, based on the heat balance equations for both anemometric and thermometric wires, was refined and applied to compute the gas velocity from the anemometer output signal. The gas property influence, the thermometric sensor lag and the prong temperature effects were taken into account with this procedure. The in-cylinder velocity data were reduced using both a cycle-resolved approach and the conventional ensemble-averaging procedure, in order to separate the mean flow from the fluctuating motion.

For the increased requirements on computer automatization and data evaluation in the field of emission testing, new programming / computer - technologies are required. To fulfill the requirements of the programmer and the user of the software, Windows NT with object oriented programming was found to provide the best possibilities to control such highly automated, complex systems. Under these directions the new Emission Test Cell Computer (short ETCC) was developed with use of the latest software and hardware technology. The Test Cell Computer provides a control system with integrated storing and paperless documentation of all relevant test data as well as protocols with all today's possibilities to create printouts. Also the managing work necessary for multiple tests running in parallel at the same time in different rooms with progress monitoring is included. The ETCC can easily be integrated into network environments and connected e.g. to existing networks.

A new computerized test control and data acquisition system for experimental testing of transmissions has been developed. The purpose of the test system is to provide a better transmission product by facilitating test activities, which include performance, development, and durability testing. The test system is capable of handling many different models of automatic and powershift transmissions, varying in size, horsepower, and complexity. The system is dedicated to test cell operation and is not used for non-test-related functions. It is a mini-computer-distributed system commonly referred to as a hierarchical system. The system consists of satellite, intermediate, and host computer levels. It is used in conjunction with ten engine-powered test stands and six DC-dynamometer-powered test stands. This paper covers operating and system features of the overall test system.

Compatibility of coolant concentrate and SCA/water mixtures can be measured by their tendency to form insolubles during short term exposure to simulated operating conditions. A relatively simple, basic compatibility method was chosen to study the amount of silicate gel formed by coolant concentrate/SCA/water mixtures.. The method was modified to improve precision by first studying, then controlling key experimental factors. Further refinements were made to the method and a precision round robin was performed as part of the activity of the ASTM Committee D.15 on Engine Coolants.

Conventional laboratory screening tests have not provided a completely reliable basis upon which to predict the service life of high performance automotive hose. The limitation of most test procedures is that they fail to simulate combinations of environmental conditions likely to be encountered in service. A high temperature immersion/flexure machine has been developed that eliminates the limitation of past test procedures. It is capable of rapid and accurate evaluation of tube candidates. This new procedure offers the potential for the examination of properties of a wide variety of elastomeric compositions before resorting to costly and time-consuming fabrication of hose required for impulse and field testing. The results to date have shown excellent agreement with data obtained from long-term hose impulse.

Typically the velocity dependent hydraulic damper characterization is done using a sinusoidal input to the damper. Damping force vs. displacement and velocity plots are used to represent the damping behaviour. It was observed that the dampers exhibit equal damping characteristics using this conventional method, shows a significant difference in ride comfort levels of the vehicle. This behaviour primarily arises due to the variation in response of the damper with the excitation frequency. On actual riding conditions, apart from harmonic loads, the suspension experiences impact loads that affect the damping generation characteristics. So the damper also needs to be characterized with variation of frequency ranging from 0.5 Hz to 25 Hz. Due to the limitations of damper stroke and input frequency, complete characterization of damper is not possible with sinusoidal input test rig.

A new laboratory test for measuring catalyst oxygen storage capacity has been developed. The test accurately predicts catalyst performance on the vehicle during transient A/F excursions and correlates well with vehicle CO and Nox tailpipe emissions. The test was subsequently used to facilitate improved oxygen storage capacity for new Pd-only washcoat formulations.

As the automotive industry increasingly adopts Advanced High Strength Steel (AHSS) for the vehicle light-weighting and crashworthiness, the edge cracking significantly increases in stamping AHSS. Different lab-scale test methods such as the ISO standard hole-expansion test and the half specimen dome test are available to evaluate edge formability. However, none of these lab-scale testing methods emulates production conditions such as various shear clearances, part complexity, and shearing speed associated with the mechanical or hydraulic press operation. To address these limitations of the available testing methods, a new punching and stamping test was developed. This paper introduces the simulation and experimental approach in developing this unique testing method to design the peanut-shaped hole that is sensitive to edge cracking in stamping.

We have made a new rig of the friction and wear testing rig which researches the slipping and adhesive wear characteristics of the automobile elements under vibrating and loading conditions, and also evaluates the effect of lubricating oil on the friction and wear of materials. The dynamic characteristics of the tribology of materials can also be assessed with this testing rig. This tester can automatically and synchronously measure and record the dynamic friction force, the coefficient of friction, and the resulting pressure during the tests. The tester has been equipped with a microcomputer which samples displays and records the test results. The tester is sensitive of good reproducibility, and achieves consistent results.

Synthesis of a new type of FEPM (tetrafluoroethylene-propylene alternating copolymer), its curing behavior and physical properties were studied. Recently, the concern of heat, motor oil and chemical resistance of the elastomer material has been growing and the performance of FEPM, which has excellent chemical and oil resistance against organic and inorganic acids and bases, especially amines even at elevated temperatures, has drawn considerable attention. However, there were some requirements for FEPM to improve its physical properties. In order to resolve the problem, some studies have been made, but the results of the studies were insufficient. Especially, its compression set is over 30%. In this work, modification of FEPM copolymer was studied to improve the cure stability and physical property as well as mold release, and a new type of FEPM was developed. This new FEPM has a specific cure site which can be introduced quantitatively into the tetrafluoroethylene-propylene backbone.