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The future of Alternative Fuel Vehicles (AFVs) is uncertain because consumer demand for them has not been established. AFVs are environmentally friendly and have the potential to provide short, mid, and long term solutions to the United States' problem of dependence on foreign sources of oil. At this time, however, there is little economic incentive to encourage consumers to purchase AFVs. The federal government has taken the lead in establishing a market for AFVs by mandating their purchase across federal and state vehicle fleets. In addition, the government has offered incentives to automobile manufacturers to encourage the production of AFVs. The government has also established consumer awareness programs which are educating the public about the benefits of AFVs. It is basic government research, however, which is the key to maximizing the long term potential of AFVs.

Laser Doppler velocimetry, phase Doppler anemometry and Mie scattering were applied to a single-cylinder, four-valve, spark-ignition gasoline research engine equipped with a fully transparent liner and piston, to obtain information about the tumble flow and the droplet size and velocity distributions during induction and compression, for lean air/fuel mixture ratios of 17.5 and 24 and with closed-valve and open-valve fuel injection. The mixture distribution obtained with the two injection strategies was correlated with flame images, pressure analysis and exhaust emissions which confirmed the advantages of combining open-valve injection with tumble to allow stable and efficient engine operation at an air/fuel ratio of 24 through charge stratification and faster flame growth.

Composites of oxyPAN and phenolic resins, with and without additives, were moulded by hot compression and used as friction material for automotive brake pads. Moisture content, relative density and ShoreD hardness measurements and Krauss Friction tests were performed with the prepared samples. The composites seem to be strongly influenced by the temperature, with friction coefficients out of the target range (0.30-0.35). However, the friction levels of the composites formulated with metallic and ceramic additives (a total of only four constituents) were comparable to commercial brake pads, with an average coefficient of 0.34, a minimum of 0.26 and a maximum of 0.58.

Vehicle aerodynamic development is normally undertaken in smooth flow wind tunnels. In contrast, the on-road environment is turbulent, with variations in the relative velocity experienced by the moving vehicle caused mainly by the effects of atmospheric turbulence. In this review the turbulence inherent in the atmosphere is considered, following the approach of wind engineers. The variations of atmospheric wind velocity with time, height, terrain and thermal stratification are summarised and discussed. Statistical parameters presented include mean velocity, turbulence intensities, spectra and probability density functions. The resulting fluctuating approach flow (relative velocity) of the moving vehicle is then considered. The effect of the fluctuating velocity field on parameters of interest to vehicle aerodynamicists (such as aerodynamic noise) are made.

Technology has undergone unprecedented growth and expansion that is beginning to overwhelm Businesses as they evolve to new structures. The current estimate is that we generate an entire new level and breadth of knowledge every 13 months. Decision Science has embraced a new technology to deal with this situation. This technology is known as Group Decision Support Systems (GDSS). In the environment of SAE Manufacturing Engineering Activities, there are enormous advantages in using GDSS. When combined with the Value Methodology process, professionals and Businesses can generate that necessary competitive edge to overcome the gap between this new knowledge and our current business practices.

New ductile cast iron flywheel integrated with gear and its manufacturing process were developed to reduce the manufacturing steps and cost compared with conventional flywheel around which a steel ring gear is fit. In this process, the ring gear teeth around a cast iron flywheel are formed directly in net shape and free from any defect by the hot form-rolling method, followed by the thermomechanical treatment in a short time. The gear is superior to that made by the conventional hobbing and heat treatment in accuracy, strength and anti-wear property.

This paper chronicles a heat exchanger development project that utilized an integrated development process. A combination of full-scale heat exchanger performance testing, flow visualization experiments, and computational fluid dynamics methods were used in concert to investigate flow phenomena in multilouver fins. The primary goal of this project was to confirm the flow and heat transfer enhancement mechanisms at work in multilouver fins. A second goal was correlation of flow visualization, CFD, and traditional full-scale heat exchanger testing. Excellent agreement was found between the three methods.

A useful analysis method of excitation forces and powerplant vibration caused by engine operations has been developed, intended for a powerplant which consists of a horizontally opposed 4-cylinder engine and a longitudinally mounted transmission. The developed method uses a commercial mechanical dynamics solver to calculate the excitation forces which involve the effects of crankshaft vibration and main journal clearances. Also a vibration analysis model of the powerplant is built using the results of experimental modal analysis, for the prediction of powerplant vibration levels. The calculated result was verified by the measured vibration data, and it was confirmed that this analysis method can predict the low order components of powerplant vibration with reasonable accuracy.

This paper deals with the problem of complex engine part analysis. It presents an original approach based on the use of X-ray Computed Tomography scan digitizing method. In comparison with classical digitizing method, Computed Tomography method proves to be the only solution in the case of complex parts with internal areas. A validation example for which the precision of the method is estimated, is proposed. At last, the potential of the method is illustrated through the complex example of an engine head cooling circuit for which a computational CFD calculation is made.

One of the main types of window regulators that are in current use is the X-arm type window regulator, which utilizes a linkage mechanism to raise and lower the window glass. One of the evaluation items that are necessary in analyzing the performance of a window regulator is the operating force that is required to operate the handle for moving up the window glass. It is difficult to estimate this force during the design stage. We have to take into consideration factors such as the influences of the various types of contacts and the elastic deformation of linkage arm. Therefore, we used the LS-DYNA, which is dynamic and kinematic nonlinear finite element analysis code, to develop a technique for analyzing the handle operating force. Then, we used this technique to conduct parameter studies to identify the factors that are believed to exert a greater influence on the operating force.

Computer aided design of battery management systems requires mathematical models and software to simulate the storage devices under investigation. For lead-acid batteries a suitable model and an appropriate software package have been developed at the Control Engineering Department of the Institut für Solare Energie-versorgungstechnik in Germany. The software represents the physical and electrochemical structure of those batteries and can be initialized by some geometrical data, the amount of substances in the electrodes and the values of porosity for the separators and the electrodes in charged state. Originally the model has been designed for condition monitoring systems, but for some time, it has been used also by some enterprises of the automotive industry to simulate complete electrical networks. Of course it can be used for cell design applications, too.

Neck injuries occuring in rear impacts, often referred to as “whiplash” injuries, have become one of the most common types of injury in car accidents and the number is growing steadily in many countries. One effect of this is that more than half of the medical insurance compenstaion to car accident victims in, for instance, the United States or Germany is related to “whiplash” injuries. The alarming increase in injury incidence has increased research and product development efforts worldwide. In 1997 (US early 1998), SAAB introduced the SAAB Active Head Restraint (SAHR) in the all-new 9-5 vehicle as a first application of crash activated systems to mitigate whiplash injuries. In addition to the active head-restraint, the SAHR system comprises design features in the seat-back to control and distribute those loads on the occupant that are generated in rear impacts or during rebound from the restraint system in frontal impacts.

The object of this study is to investigate a principle of obtaining stratified charge in spark ignition engine. The stratification is obtaining in a large prechamber which comprises 50% of the compression volume and which is connected to the main combustion chamber through a relatively large flow transfer passage. The fuel is injected (at any load) into the transfer flow passage, during the compression stroke and the air-fuel mixture is carried toward the spark plug. The control of mixture stratification and emissions can be achieved by the injection timing variation. The values of the specific fuel consumption and specific NOX emission are of the same level comparing to the values obtained for a Diesel engine with divided combustion chamber. While combustion stability at very lean operation is guaranteed intake air throttling in the part load range is necessary to keep combustion temperature high enough for effective oxidation of CO and HC.

A new spray model has been developed to improve the prediction of diesel engine combustion and emissions using the KIVA-II CFD code. The accuracy of modeling the spray breakup process has been improved by the inclusion of Rayleigh-Taylor accelerative instabilities, which are calculated simultaneously with a Kelvin-Helmholtz wave model. This model improves the prediction of the droplet sizes within a diesel spray and provides a more accurate initial condition for the evaporation, combustion, and emissions models. An improvement to the droplet drag model is also presented. This model accounts for the increased droplet drag due to the change in the droplet's shape, as well as the increase in the frontal area of the droplet. The drag model affects the breakup process locally, producing a more realistic droplet size distribution, and therefore a more accurate calculation of the vaporization process.

Despite the increasingly stringent emissions legislation, users and owners of commercial diesel vehicles are continually demanding that each new engine generation is more economical than the previous one. This is especially important for commercial vehicles where the majority of engines are in the 1-2ltr./cyl. class. The demands are being reflected in new engine designs with lower friction and improved structural stiffness, together with fuel systems having increased pressure capability, higher spill rates, injection rate shaping and advanced control features. These fuel system requirements have led to a variety of new fuel injection systems and in the search for increased injection pressure these fuel systems have placed greater demands on the engine, especially in areas such as the cylinder head and fuel system drive, sometimes with adverse effects on the combustion and fuel injection system induced mechanical noise.

Air can be enriched with oxygen and/or nitrogen by selective permeation through a nonporous polymer membrane; this concept offers numerous potential benefits for piston engines. The use of oxygen-enriched intake air can significantly reduce exhaust emissions (except NOx), improve power density, lessen ignition delay, and allow the use of lower-grade fuels. The use of nitrogen-enriched air as a diluent can lessen NOx emissions and may be considered an alternative to exhaust gas recirculation (EGR). Nitrogen-enriched air can also be used to generate a monatomic-nitrogen stream, with nonthermal plasma, to treat exhaust NOx. With such synergistic use of variable air composition from an on-board polymer membrane, many emissions problems can be solved effectively. This paper presents an overview of different applications of air separation membranes for diesel and spark-ignition engines. Membrane characteristics and operating requirements are examined for use in automotive engines.

One of the causes of rejections for part breakage on automotive sheet steels at stamping plants is insufficient pre-applied lubricant (prelube) on the blank. There are several key processes that occur after the prelube is applied at the steel facility that can affect the prelube amount and distribution before the blank is stamped. To understand the effects of these key processes, a controlled study was performed to examine the effects of prelube application level, coiling, coil storage, blanking, lift storage, and blankwashing on the amount and distribution of prelube. After mill application, the prelube migrates from the center to the edge resulting in reduced oil levels (“dry spots”) in the center of the coil or blank. It was found that coiling and coil storage had the greatest effect on prelube migration. Extended lift storage resulted in continued reduction in prelube level at the center of the blank, but at a decreased rate.

A new press/die system for restraining force control has been developed in order to facilitate an increased level of process control in sheet metal forming. The press features a built-in system for controlling drawbead penetration in real time. The die has local force transducers built into the draw radius of the lower tooling. These sensors are designed to give process information useful for the drawbead control. This paper focuses on developing models of the drawbead actuators and the die shoulder sensors. The actuator model is useful for developing optimal control methods. The sensor characterization is necessary in order to develop a relationship between the raw sensor outputs and a definitive process characteristic such as drawbead restraining force (DBRF). Closed loop control of local specific punch force is demonstrated using the die shoulder sensor and a PID controller developed off-line with the actuator model.

Prephosphating of galvanneal steel sheet has been shown to improve its forming performance. This improved formability is due to a reduced coefficient of surface friction caused by the prephosphate treatment. Also, increased levels of powdering have been observed with prephosphated galvanneal sheet during cup-drawing operations. It has also been shown that powdering is strongly dependent on the strain state, especially the compressive strain component, during the forming process. Combining these two observations, a possible explanation for the increased powderability of prephosphated galvanneal may be that the prephosphate treatment alters the strain state during the forming of galvanneal sheet, which in turn impacts the powderability. In order to examine this hypothesis, cups were drawn from delta-phase galvanneal sheet samples which were subjected to various prephosphate treatments. The changes in strain state along the walls of the cups were measured using circle grid analysis.

The costs for development and production of draw dies for car outer panels are extremely high and should be reduced. Furthermore it is necessary to reduce the time for developing, designing and producing the dies for the production of parts. This paper discusses new press techniques, die designs and an adjustment program for press operators. The trend goes to single action presses with CNC-controlled multipoint cushion systems in the press table and to special designed dies. These systems lead to a more robust and reproducible forming process with improved product quality. This paper deals with: Cushion Systems, New Binder Designs for Draw Dies for Sheet Metal Automotive Parts, New Computer Program to Adjust the Blankholder Forces of Modern Hydraulic Cushion Systems of Single Action Presses and Pressure Measurement for Detecting the Pressure between the Blank and the Binders of Draw Dies for Sheet Metal Automotive Parts.