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The compatibility of biodegradable fluids (1) with copper-based alloys was found to be an important requirement for high-pressure mobile hydraulic systems. Existing test methods (2)(3)(4), are not suitable for determining the practical requirements for biodegradable oils, nor do they encourage or contribute to further development of such fluids. Our laboratories developed a screening method capable of establishing correlation between field experience and the results of accelerated tests. Test parameters include copper-alloy materials, temperature, different mixtures of biodegradable oils with mineral oils and water, as well as the simulation of mechanical activation of the ‘corroding’ surfaces. It is suggested that the ‘Linde-test’ provides a simple, quick and low-cost laboratory method to determine the compatibility of biodegradable oils with copper-alloys in hydraulic systems under conditions representative of practical applications.

Various methods for evaluating the effectiveness of debris resistant bearings have been proposed for development. Once evaluation methods are well established to select bearings, the user is faced with assessing severity and detrimental effects of a specific application's lubricant contamination on bearing performance. Many analysis tools have been suggested for determining this impact, including particle analysis for size distribution, type of material and contamination level. A novel approach for determining severity of damage has been investigated which attempts to integrate these typical tools with actual damage to functional surfaces. It seeks to provide a practical approach and is appropriately labeled Debris Signature Analysis. Results of actual assessments will be discussed and the assessment method described.

The results of the comparison of actual dynamic frontal crush behaviour from initial contact to maximum dynamic crush of 8 cars in 45% frontal overlap and 30 degree rigid barrier impacts at 50 and 56 kph respectively with the predicted responses from an overall frontal crush model are presented. The model used is based on the assumptions of the overall front structure deforming in a geometric manner and of the energy absorption properties in the full width barrier impact being the same as the energy absorption characteristics in other frontal crush configurations for identical average crush depths. The model uses a fundamentally different method of calculating average crush depth to that used in CRASH.

The first single-piece, injection-molded, thermoplastic, front bumper for a light truck provides improved performance and reduced cost for the 1997 MY Explorer® Ltd. and 1988 MY Mountaineer® truck from Ford Motor Company. Additionally, the system provides improved impact performance, including the ability to pass 5.6 km/hr barrier impact tests without damage. Further, the advanced, 1-piece design integrates fascia attachments, reducing assembly time, and weighs 8.76 kg/bumper less than a baseline steel design. The complete system provides a cost savings vs. extruded aluminum and is competitive with steel bumpers.

The 1997 F-Series and Expedition Instrument Panel programs were initially launched with steering column and glove compartment knee bolsters constructed of compression molded, glass filled polypropylene. First run capability of the material at production speeds was only 65 percent due primarily to dimensional stability (warp), paint adhesion, and excessive rework issues. A Ford APO (now Visteon) / Dow Automotive† team was formed to seek a replacement material / design for the glass filled polypropylene material which would solve the problems. The new material system had to meet or exceed current FMVSS 208 crash performance standards, provide improved quality and reduce variable and scrap costs all with a minimum tooling investment. Using Dow PULSE™ PC/ABS resin, the team designed / implemented a new knee bolster system in 12 months.

A design of a Diesel1 particulate matter (PM) filter system for heavy duty vehicles is presented. The system consists of two ceramic catalyzed filters connected in parallel, so that one is in operation while the other one is in stand by or during regeneration. The regeneration (cleaning) process is carried out through the injection of a hot air flow in inverse direction to the filtering process. The air is heated by a thermal energy storage device (Thermal Inertia Device, TID). A catalytic washcoat reduces the carbon activation energy in order to incinerate the (PM) at lower temperature levels. The system has a control and monitoring electronic circuit based on a micro-controller.

Since the Californian ZEV mandate caused a new wave of interest in the electric automotive propulsion system to sweep over the world, the question of why earlier attempts to bring the electric vehicle to the market failed is heavily debated. As to the possible causes of failure of the electric vehicle during the first two decades of this century, the consensus among automotive engineers tends to be that it was the high weight and the low energy density of the battery which prevented the electric motor from becoming the dominant automotive propulsion system. Since then, this argument goes, the situation hasn't changed very much. In this paper, based upon a recently finished doctoral dissertation on the history of early American and European electric vehicles [1], other, mainly non-technical, failure factors are suggested as being more convincing.

The fuel cell bus program at Georgetown University (GU) has directed the operational development and testing of three hybrid fuel cell powered buses for transit operation. These are the world's first liquid-fueled, fuel cell powered road vehicles. This paper describes the emissions testing of one of these buses on a heavy duty chassis dynamometer at West Virginia University (WVU). The tested bus was driven by a 120 kW DC motor and utilized a 50 kW phosphoric acid fuel cell (PAFC) as an energy source with a 100 kW battery for supplemental power. A methanol/water fuel mixture was converted by a steam reformer to a hydrogen rich gas mixture for use in a fuel cell stack. Emissions from the reformer, fuel cell stack and startup burner were monitored for both transient and steady-state operation.

This paper discusses controller development for an active, off-road vehicle suspension system. A brief review of electronic filters and their characteristics is used to provide insight on the difficulties of designing a control algorithm for negotiating hilly and rough terrain at higher speeds. Two controller designs are presented. One was designed by pole placement and causes the suspension response to approximate a Type 1 Chebychev filter. The other was designed using constrained optimization. A comparison and discussion of simulation results leads to the conclusion that the suspension should be adaptively or predictively controlled for arbitrary terrain and velocity conditions.

In this study, a series of tests have been carried out to evaluate the effects of the injection rate and timing on bsfc, NOx, and PM emissions in a heavy-duty diesel engine with TICS FIE system. Injection line pressure, cylinder pressure, NOx and smoke were measured with various injection times and injection rates. The injection rate was altered at a fixed injection timing, which could be realized either by changing the TICS setting time or by using different cam profiles. The injection time was varied by using TICS timing control function at a given setting time. A parametric study of the injection rate in in-line pump system was tried to correlate injection rate variations with combustion characteristics and emission. Two parameters, the injection pressure rising rate and the initially injected fuel quantity were introduced to characterize fuel injection.

Effects of fuel properties, in terms of the 90% boiling point (T90) and the polycyclic aromatic hydrocarbon (PAH) content, as well as oxidation catalysts on diesel exhaust emissions have been examined using three direct injection (DI) diesel engines and two diesel passenger cars equipped with oxidation catalysts. The diesel emission tests using two series of test fuels, one for examining the effects of the T90 and another for polycyclic aromatic hydrocarbons, have indicated that total hydrocarbons (THC) and particulate matter (PM) decrease as the T90 is reduced. PM and THC were also found to be on a declining trend with a decreasing content of polycyclic aromatic hydrocarbons. The extent of these effects of fuel properties on exhaust emissions varied with engine and car models, and appeared to be smaller in engines or cars having lower exhaust emissions.

A new 12.5 L four-valve heavy duty diesel engine has demonstrated that Powdered Metal (PM) is an effective material alternative to wrought steel for the valve bridge. The valve bridge, an element that spans the pair of intake or exhaust valves, allows a single rocker arm to actuate the pair of valves. The component is subjected to a high number of cycles at a moderately high load and geometry precision is essential for desirable wear characteristics. The PM material selected, MPIF FL4605-120HT, has replaced 8620 steel after making component geometry changes. The PM part has a higher load capacity than the original design with equivalent wear characteristics and offers a 80% cost saving over the original design. This paper presents the geometry changes defined by FEA analysis and component testing performed to verify the change from wrought steel to PM. A required characteristic of this component is moderately high fatigue strength.

In the case of turbocharged heavy duty diesel engines, the total efficiency of the turbocharger is higher than for smaller turbos for passenger cars. It is difficult to recirculate exhaust gas because of higher intake manifold pressure in comparison to exhaust gas pressure. IHI has developed a new turbocharger for exhaust gas recirculation for heavy duty diesel engines. It has a recirculation port at compressor side. The port is connected with a narrow annular slit located at the diffuser inlet, where the static pressure is lower than intake manifold. The result of JIS diesel 13 mode test with this turbocharger showed 26 % lower NOx without significant penalty of fuel consumption.

The time and the distance traveled during the acceleration and the velocity retaking are parameters used for the comparison and the project of vehicles. In this paper equations for the calculation of those parameters are presented. Several criteria are presented for the shift gears. It is also verified the occurrence or not of total slip during the acceleration of the vehicle. The theoretical models were implemented in a developed computational system. Such system was applied in a Mercedes-Benz do Brazil sample vehicle, in order to facilitate comparisons between the simulate values and the experimental road tests.

In late 1996, Daimler-Benz together with WABCO and Scania together with Bosch presented the first electronically controlled brake systems (EBS) in their towing vehicles. Since then roughly 2000 ACTROS per month have been produced with EBS. Other vehicle manufacturers will introduce EBS in the near future [5]. The technical advantages of EBS combined with the increased application of disc brakes, are: improved safety through shortened stopping distance better vehicle stability and brake comfort optimized brake monitoring and higher profitability However, with this first step the technical possibilities are limited to towing vehicles combined with conventionally braked trailers. The overall braking performance of the combination unit can be further improved when the trailers are equipped with an electronically controlled brake system.

This paper presents the Vehicle Dynamics Control (VDC) for commercial vehicles developed by BOSCH. The underlying physical concept is discussed in the second section after a short introduction. The third section shows the computer simulation used in the development process. Section four describes the controller structure of the VDC system. In Section five the use and effectiveness of VDC for commercial vehicles is shown in different critical driving situations. This is done by using measured data collected during testing (lane change, circular track) and it demonstrates that the safety improvements achieved for passenger cars are also possible for commercial vehicles.

The European automotive EMC directive, 95/54/EC, provides the EMC approval regime for motor vehicles of 4 wheels or more and all equipment intended for fitment to them. The EMC Chapter of the European multi-directive for 2/3 wheeled vehicles, 97/24/EC, provides the approval regime for these vehicles and their equipment. Regulation 10 of the United Nations Economic Commission for Europe (ECE) is being updated to provide similar EMC requirements. ISO draft standards are available for forestry and agricultural tractors, and for earth-moving machinery. This paper explains the relationship of these different approvals to the general EMC directive, 89/336/EEC, and offers interpretations for vehicles and their components as well as the implications for the various types of aftermarket components.

Transmission shift lever jumpout is a truck system dynamics problem that is caused by engine/transmission pitching in response to rough road input. Severe rotational motion imposes inertial forces on the shift lever system, potentially causing the shift rail to move to neutral. Dynamic testing and analysis has led to suggestions for system design improvement including lever geometry optimization and engine mount stiffness and damping improvement. A counterweight addition to the lever system will also stabilize the dynamics.

Tests of class 2,3,and 5 straight trucks were made to determine the affect of aftermarket aerodynamic aids on fuel economy and handling. It was determined that the potential exists for significant improvement in the fuel efficiency of these classes of trucks.