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During injection molding of thermoplastics the filling depends on the material's rheological properties, on the characteristics of the mold and also on the process parameters. Thanks to the elaboration of short shots, it is possible to reconstruct the main successive steps of the filling and to know the advancing melt flow. The choice of specific cavities and particular injection gates allow for filling to be studied in many different cases. The disposition of barriers inside the cavities gives opportunity to orient the flow. Experimental studies consider the injection of polyester and polyamide unfilled and reinforced with short glass fibres. Original results in terms of filling are shown on images. We compare experimental fillings with theoretical fillings obtained with a rheological simulation software. Good agreement is proved for unfilled materials.

In the design phase of aluminum wheels for passenger cars, the wheel's ability to withstand low speed side impacts with minimal damage inflicted to the wheel is of major concern. There are two side impact test standards available today. The one that appears to better simulate an actual wheel-curb impact situation is the SAE J175-88. Part of the test setup includes a deflection check of elastomeric shock absorbers under specified load. The authors have devised a technique to obtain the data for this calibration from a monotonic load/displacement curve. Curve fitting is followed by intercept calculation and a check against specifications. The specified elastomer deflection range under load dictates the expected dynamic response in the actual test. Therefore, in addition to the SAE recommended natural rubber, the authors also investigated the deflection characteristics of alternative polymeric materials, such as EPDM, neoprene and urethane.

Over the last ten years, the plastics industry has been under pressure by many industries, such as automotive, to resolve issues from an application point of view, such as value engineering, part quality, and time to market. Value engineering programs have been a major thrust for the last several years in many industries. These programs have taken the form of low cost materials, systems integration, part weight reduction, and lower fabrication costs. The automotive industry, forced by foreign competition during the 1980s, has also led the way in providing an emphasis toward improved part quality resulting in longer part life cycles. In addition, automotive producers are shortening their design engineering phase which has caused the plastics industry to find methods to more rapidly move technology from research and development to end-use applications.

The amount of carbon and the kind of fixing carbon to supporting structures influences the air permeability and adsorptive efficiencies, which are shown for n-butane, toluene, sulfur dioxide, nitrogen dioxide and ozone.

The performance of the air cleaning filter is important to the long-term performance and reliability of the engine and its components. In this study, the performances of cellulosic and foam filter media for engine air cleaning application are experimentally investigated. Phenolic and non-phenolic cellulose filters were studied. Both flat-sheet and pleated cellulose filters were included. The foams filters were reticulated polyurethane foam media from 20 to 110 pores-per-inch. We measured the initial air flow resistance, the collection efficiency as a function of particle size, and the behavior of dust loading. We also studied the effect of oil treatment on filter performance. The results show that the efficiencies and pressure drops of the cellulose filters increase rapidly with dust loading. Oil treated cellulose filter was found to exhibit slower increases in pressure drop and collection efficiency, resulting in higher dust holding capacity.

The problem of defining mathematical descriptions for instantaneous discharge coefficients of valves and ports for turbocharged engine has been solved. The developed procedure for identification is based on the simultaneous consideration of the mathematical model of the gas-exchange processes and the experimental ‘pressure-crank angle’ histories for the same process. As a result the instantaneous discharge coefficients can be defined by the valve / port geometry, valve lift and pressure ratio. An actual problem for a two-stroke uniflow-scavenged turbocharged engine has been solved. The obtained mathematical descriptions for the discharge coefficient can be used for other engines.

The paper describes a procedure for optimizing the cam profile of a pump in a diesel fuel injection system by employing an approximation method of mathematical programming. The shape of the profile is represented by a Bézier curve and some of the coordinates of the control points are adopted as design variables. The objective function is build upon a target shape of the pump plunger velocity while the imposed constraints are related to the local radius of the cam profile, pump plunger acceleration and to the design variables. The procedure is appropriate to be included into the optimal design procedure of the whole fuel injection system. The theory is illustrated with numerical examples.

Automobile cabin air filters may encounter a variety of environments and contaminants. Several environmental conditions and contaminants from the application are identified. Simple, repeatable surrogate laboratory tests are described. The tests are performed on a range of filter media. The results are presented. The tests provide results that differentiate between filter media that is expected to perform well in the application and media that is not expected to perform well.

Design of the pressure pumping mechanism in a distributor fuel injection rotary pump becomes an uneasy task due to the restless demands for raising injection pressure. This paper presents a numerical simulation model developed to analyze the design appropriateness of the cam ring, roller, and shoe components in the pumping mechanism based on their tribological performance. The developed model solves the lubrication of cam/roller and roller/shoe interfaces simultaneously. Lubrication of the cam roller interface is modeled with a mixed lubrication concept to include the surface asperity contact effects. The load-carrying capacity of the surface is characterized by using a contact mechanics model with the measured surface profiles. Assuming the shoe body is rigid, the roller shoe interfacial lubrication is treated as a partial hydrodynamic bearing including the effect at roller slippage.

In recent years, traffic fatalities in Japan have consistently numbered in excess of 10,000, making them a serious social issue. Among these deaths resulting from traffic accidents, fatal accidents occurring at night outnumber daytime fatalities by three to one; when conditions are rainy, this figure increases to ten to one. These facts point to the importance of the role of automobile forward lighting systems. In order to provide enhanced nighttime safety measures, we have been working since 1990 on the development of a headlamp system that can control and adjust the headlamp beam in response to driving conditions. In this report, we will outline the general features, functions and lighting performance of forward lighting systems, focusing on this newly developed headlamp system.

This paper deals with the particle distribution in Diesel spray under the non-evaporating condition from the analytical aspect based on our experimental results. In the analysis, TAB method of KIVA II code and the k-ε turbulent model were used, and the mono-disperse distribution of the initial parcel's diameter, whose size equals to the nozzle hole diameter, was utilized in conjunction with the breakup model. The size distribution of atomized droplets (i.e. the χ-squared distribution function) is justified with the degree of freedom. It is shown that the ambient gas, which is initially quiescent, is induced and led to a turbulent gas jet. The turbulent gas jet which has a equivalent momentum with the Diesel spray was also examined by Discrete Vortex method. The quantitative jet growth was shown to be possible for the estimation and determination in its initial boundary values at the nozzle.

Light distributions of headlamps are defined as static values. Neither FMVSS nor ECE allow variable beam pattern for low beam headlamps. New electronic systems and sensors available for car applications facilitate a situative. lighting that prepares an optimum lighting for each driving Situatuion. This paper shows the necessity of different beam patterns for certain driving situations. Based on an road geometry analysis and an investigation of objects in the street the optimum ligh! dictrihutionr are carried out for the single situations.

In most cases of night time driving the low beam light function is used for the road illumination in front of the car. This conventional low beam function has a constant light pattern: no matter whether the driver is actually driving on a straight or curvy road, whether the road is wet or dry, always the same beam pattern is applied. Test experiences of the last years prove that a headlamp with an „adaptive light pattern” having different optimum light pattern adapted to different driving situations should give a better illumination than the conventional constant low beam pattern which can only be a compromise. In this paper an outline of the basic idea of the „adaptive light pattern” is given. Different driving situations and their corresponding optimum light pattern, basic technical concepts and the legal situation regarding homologation of such an advanced lighting system will be discussed.

Lighting and signaling functions are key factors for road safety and driving comfort at night. Night-time traffic represents 20 % of total mileage, but generates more than 50 % of fatalities. This percentage is even nigher in adverse weather conditions. New developments are being proposed to improve safety when driving at night. Systems which take account of environmental factors modify the beam pattern in accordance with driving conditions. Automatic beam modification is one of several projects grouped together in the wider approach known as Intelligent lighting. This approach differs from current vehicle lighting techniques which, being based on legal and regulatory requirements, entail design and testing in static conditions. Intelligent lighting involves electronic data acquisition and processing, with the target of altering the shape, the relative intensity, the aim and the direction of the headlamps in accordance with the prevailing conditions.

For the current class of available automotive LEDs (Light Emitting Diodes) used in CHMSLs (Center High Mount Stop Lamps), voltage regulation is required for operation at an optimized output light flux. We have built and measured the performance of resistive, voltage reference, and pulse width modulation DC-DC voltage regulators in order to achieve the required dual level control for RCL (rear combination lamps). These three types of driver electronics for dual level operation of a RCL are compared for performance, and efficiency under various operational conditions.

A modular frontlighting concept is proposed, which allows easy and quick introduction of new lighting technologies without major redesign.

The highest fatal traffic accident rate occurs on a curved road at nighttime. The “Active Headlight (AHL)” system developed by Honda R&D and Stanley Electric is the system that the beam pattern of the headlamp changes and more headlamp light is distributed toward a curve direction. The AHL system can direct alighttoward a curve before the vehicle enters a curve by using road information from a navigation system. When the AHL system moved in nighttime, visibility on curves and stability of driving were improved and glare to an oncoming vehicle was acceptable.

If a tail light bulb burns out, the failure will be detected by an electronic light check module. The missing tail light will be substituted by the stop light function. The luminous intensity of the stop light will be automatically reduced to the tail light level. If a car is equipped with rear fog lights, a faulty brake light can be substituted, similarly by a reduced rear fog light. Today the hazard warning signal has the same frequency as the turn signal indicator. If one side of a car is blocked by for example another car then it is not possible to differentiate between the aforementioned signal types. Therefore the hazard warning information is lost. The suggested new hazard warning signal consists of a double-flash with a short break, the time period is nearly unchanged.

The goal of this study was to provide information about the frequency of installation and use of fog lamps. Two surveys were performed. In the first one, installation of fog lamps was estimated by a survey of parked vehicles in two iarge shopping centers. The second survey studied the usage of fog lamps during daytime and nighttime, under clear, rainy, or foggy conditions. In this survey, an observer in a moving vehicle noted the types of lamps that were energized on the fronts of oncoming vehicles, and whether fog lamps were installed at all. The main findings are: (1) The best estimate of the current frequency of installation of fog lamps in southeast Michigan is about 13%. (2) During daytime, the usage of fog lamps increased with deterioration in atmospheric conditions, with the usage reaching 50% of all installed fog lamps during moderate-to-heavy fog.

The automotive lighting industry has undergone major changes over the past 25 years. The sealed beam lamp, the industry standard for half a century has been replaced by a number of new aerodynamic headlamps. Over this same time period signal lighting has undergone dramatic changes; from a standard hand signaling for brake and turn, to complex multi-cavity systems for running, turn, and stop lighting. In the interior of the vehicle similar changes have also occurred which have dramatically improved driver visibility of the instrument cluster. In all three application areas major changes are continuing to occur particularly in the light source and optics of the illumination system. This paper discusses some of these changes and compares the various light sources and optical systems used to illuminate the space around the automobile and the communication between vehicles.