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Using an electric hybrid leads to a significant improvement in vehicle fuel economy. Unfortunately, it also leads to a substantial increase in cost. Regenerative compression braking offers another way to achieving the same objective without incurring the same cost penalty. With some modifications, the vehicle engine can perform both absorption and recovery of braking energy, using compressed air for energy storage. The process parallels the one employed by electric hybrids, but it requires none of the expensive electric equipment used in hybrid systems. This paper reviews basic principles of regenerative compression braking and its advantages in comparison to electric hybrid systems. It also describes the required changes in engine system and methods of control. Description and mathematical analysis of applicable thermodynamic cycles is given, including computations of cycle efficiencies and indicated mean effective pressures produced during braking and acceleration.

In the near future, technical demands for powerful electric motors integrated into the drive train can be fulfilled. These motors combine the functionality of starter and alternator offering a higher electric power than conventional alternators. At low engine speed, they can work as a motor and introduce an additional driving torque in the drive train (booster). The required introduction of suitable electrical storage devices enables regenerative braking to reduce fuel consumption significantly. In this paper, for homologation tests and customer use, the potential savings of regenerative braking are shown for a variety of engines, vehicles and test cycles.

The Parallel Combustion Two-Stroke is an internal combustion engine utilizing a hypocycloid gear mechanism and parallel combustion chambers. The hypocycloid mechanism provides mechanical balance and linear rod motion which eliminates piston sidewall forces and creates two chambers in the working cylinder. These two chambers are connected to combustion chambers external to the working cylinder. The resulting engine operates on a two-stroke cycle with many of the advantages of a four-stroke engine. It operates as an internal combustion engine with many of the advantages of an external combustion engine. And it operates as a reciprocating engine with the dynamic balance of a rotary engine.

At Robert Bosch North America the answer is yes. This paper will outline how we answered the question: What is Supply Chain Management at Bosch in North America? We then used the answers as a template for our Purchasing Associate Training Program. Bosch North America has over $5 billion in sales, approximately 70% in the Automotive Sector and purchased materials and services represent roughly 50% of that amount. As responsibilities shift from our customers to Bosch and as modules and systems become more complex - and involve a more complex supply chain - we must understand and manage our supply chain effectively. We realized that to a large extent concepts, strategies and processes were available, but there was no “big picture” or connection that was easy to understand and utilize in the day to day function.

In 1993, Siemens AG launched a worldwide initiative called Time Optimized Process (TOP). This program was revitalized and updated in 1998 as Time Optimized Process Plus (TOP+) and implemented at all Siemens facilities. The program has been credited with cost reductions from 2-3% to about 10%, doubling the number of registered innovations to more than 6,000, and increasing sales by 35%. TOP+ is a philosophy of how business will be conducted. It embraces many highly effective traditional tools such as Balanced Scorecards, World-Class Benchmarking, Employee Idea Systems, and Economic Value Added (EVA). A more creative tool used is Process Optimization With Early Results (POWER) teams. POWER teams are cross-functional teams with dedicated time and resources, committed to achieving goals and objectives in a very short period of time. The TOP+ program encompasses cultural change, productivity, innovation, and best practice sharing, to increase customer benefit and increase company value.

This paper describes “target costing” as a key element of the cost management function utilized by the Purchasing Division of Honda of America Mfg., Inc. and its supply base. The target costing process started in the early 1990s and has steadily improved to a more efficient and effective process. Honda of America's purchasing operation is responsible for approximately 80 percent of the manufactured cost of a vehicle. Thus, effective management of the cost of parts supplied is critical in assuring that products offered to customers in the marketplace are of highest quality, yet at reasonable prices. Successful cost management also has significant impact on the profitability of the company and its suppliers.

Many methods and tools exist for continuous improvement of supplied parts in the Automotive Industry. Over the past decade BMW AG has developed close partnerships with their suppliers to ensure outstanding customer satisfaction, superior component quality and maximum supplier cost efficiency. To achieve a successful partnership, an approach was developed to improve the quality and efficiency of processes through the optimization of the entire value added chain. Whereas many programs within the Industry often focus on specific business elements, i.e. manufacturing process, quality system or logistics system, the approach taken by the BMW Group covers the complete business chain. In 1994 BMW Manufacturing Corporation, a subsidiary of BMW AG, began this same work with its North American suppliers. Over twenty-five supplier support projects have been completed over the last six years.

The introduction of occupant position sensors into automobiles raises questions about the response of these sensors to current crash test dummies. To adequately test the performance of these sensors in a crash environment, it is crucial that crash test dummies resemble humans. Each sensor technology perceives the crash test dummy as being different from a human. These differences range considerably. The differences for four sensor technologies, capacitive, electric field, ultrasonic and pressure pattern, are described. The differences between humans and crash test dummies are discussed, along with possible modifications to the crash test dummies that improve the biofidelity of the crash test dummy. Results will be presented from testing on a mid-sized male and small female.

A finite element model of a folded airbag with the module cover and steering wheel system was developed to estimate the injury numbers of a 5th percentile female dummy in an out-of-position (OOP) situation. The airbag model was correlated with static airbag deployments and standard force plate tests. The 5th percentile finite element dummy model developed by First Technology Safety Systems (FTSS) was used in the simulation. The following two OOP tests were simulated with the airbag model including a validated steering wheel finite element model: 1. Chest on air bag module for maximum chest interaction from pressure loading (MS6-D) and 2. Neck on air bag module for maximum neck interaction from membrane loading (MS8-D). These two simulations were then compared to the test results. Satisfactory correlation was found in both the cases.

Sorbate or “trap” catalysts are capable of obtaining greater than 90% NOx conversion in lean exhaust over a wide range of operating temperatures. The critical limitation to sorbate catalysts is their susceptibility to sulfur poisoning, which is of particular concern in diesel applications where high sulfur levels exist and exhaust temperatures are typically too low for sulfur removal with thermal techniques. A novel catalyst formulation that exhibits sulfur-resistant characteristics is introduced here. The catalyst sorbs NOx and SO2. The NOx is reduced and released as N2, and the sorbed SO2 in the form of sulfates and sulfites is reduced and released as H2S and SO2. The catalyst also oxidizes hydrocarbons and CO. The catalyst system incorporates a dual-chamber design for efficient operation.

The relationship of the airbag fire-distribution as a function of impact velocity to the airbag fire-time is studied through the use of an optimization procedure. The study is conducted by abstracting the sensor algorithm and its associated constraints into a simple mathematical formulation. An airbag fire objective function is constructed that integrates the fire-rate and fire-time requirements. The function requires the input of a single acceleration time history; it produces an output depending on the airbag fire condition. Numerical search of the optimal fire threshold curve is achieved through parameterizing this curve and applying a modified simplex search optimization algorithm that determines the optimal threshold function parameters without computing the complete objective function in the parameter space. Numerical results are given to show the effectiveness and potential difficulties with the automatic search scheme.

A kind of fibrous filter made from stainless steel (SS) wire net has been developed by in our institutes. This paper is to study modeling and computing method for the fibrous filters with image effect based on the previous studies. It takes the exhaust aerosol of diesel engine as an even floating flow composed of exhaust and particulate, under the effect of electrical field force, the particulate deviate from other gas phase components and deposit on the fibers. Mathematics models for calculating the flow and the electric field, as well as the capture efficiency are given in this paper. These mathematics models are used for calculating a single fiber model.

A kind of fibrous filter made from stainless steel (SS) wire net with image effects has been developed in our institutes. The filtering medium is composed of stainless steel nets, so there are effects of neighboring fibers on different layer on the particle-capturing efficiency. We have studied the mathematics model for this filter in paper [1]. This paper mainly researches the influence of two neighboring fibers arranged in series through computing and analyzing an inline two-fiber model of the filter. The computed results point that this kind of the fiber arrangement in series is not a good choice for the fiber.

This paper describes work done on spark-ignition engine Downsizing and Super-Charging (DSC). Substantial DSC is shown to have a potential for good fuel-economy in SI-engines especially at part-load without compromising in pollutant emission levels. Built into a 4-passenger light-weight car a fuel economy of 67 M/gal (3.5 l/100km) in the European test cycle MVEG-95 was achieved with the potential to satisfy ULEV or Euro IV emission limits.

Malleable and ductile cast irons are used extensively in gearing and high strength applications within automotive power train applications. Advantages of malleable and ductile cast irons are low material cost with mechanical properties that meet or exceed the requirements of the intended application(s). One disadvantage of the malleable cast iron is the extensive heat treating required to obtain the proper microstructure and mechanical properties. Both malleable and ductile iron components require extensive machining to produce the finished component. The combination of heat treating and extensive machining often results in a component that is costly to manufacture. Recent advances in the Powder Metallurgy (P/M) process including high strength material systems and high density processing have achieved mechanical properties that meet or exceed the level achieved with the current malleable and ductile cast iron materials.

Recent demands within the automotive industry have been for applications requiring high hardness, high hardenability, and increased mechanical performance. These often conflicting requirements necessitated the development of new materials that offer high as-sintered hardness and good static/dynamic mechanical properties without the added expense of a secondary heat treatment. Traditionally, sinter-hardening materials have offered acceptable hardness but at the expense of mechanical properties and sintered density. This paper will document a series of sinter hardening materials that offer good compressibility, high hardness and enhanced mechanical properties. The discussion will focus on utilization of these materials in automotive applications (within both the engine and transmission) such as gears, cams and sprockets that are currently produced by either the press, sinter, and heat treat process or by conventional machining of a casting or wrought material.

A free piston internal combustion engine coupled with a linear generator is proposed for hybrid vehicle application. The engine works on CI two-stroke cycle with direct fuel injection. Uniflow was chosen for an efficient scavenge process. The exhaust valve timing and lift are to be dynamically controlled by electromechanical driven poppet valves, developed by FEV. A numerical simulation model of the proposed engine has been generated in this paper. The piston dynamics, cylinder scavenge process, combustion process, and friction characteristics are coupled together for systematic analysis with the code. It is meant to be a tool for prediction and optimization of the engine design and control parameters, such as fuel injection timing, valve/port timing, and electric power output. The analysis results are discussed in this paper.

Sinterhardening has proven to be an efficient and cost saving way to manufacture high strength components f.e. for gear boxes in an environmetally friendly manner. Material investigations showed that diffusion alloyed materials generally proved to be less sensitive to the hardening conditions and geometry than prealloyed materials either regarding hardness or dimensional change. As sizing of components is difficult to impossible in the sinterhardened condition, shrinkage or swelling has a decisive effect on the final dimensional stability. Compared to casehardening sinterhardening requires a significantly higher alloy content of f.e. Ni or Mo. Despite this particular cost disadvantage, the overall process provides lower costs at similiar strength levels and better tolerances.

Transfer case sprockets usually require quenching to improve hardness and mechanical properties. This additional process step can be avoided with sinter hardening. Indeed, sinter hardening allows the production of P/M parts with high strength and apparent hardness directly from sintering because the martensitic transformation takes place during the cooling portion of the sintering operation. Therefore, this process eliminates the need for a post-sintering heat treatment with all the inherent related problems such as part distortion, oil contamination and added processing costs. Many low alloy steel powders have been developed for sinter hardening applications. These materials, combined with the availability of sintering furnaces equipped with enhanced cooling capacity, make sinter hardening particularly attractive for parts that are difficult to quench because of their size and shape.

The influence of sintering parameters on mechanical properties of three different sinterhardenable grades of powder has been studied. Dimensional change, hardness, strength, and microstructure of specimens were evaluated in different sintering conditions, such as temperature, belt speed, and cooling rate. Conclusions were used to convert a major line of sprockets from a traditional mold, sinter, size, and quench process to a cost effective mold and sinterhard one. Mechanical tests, such as crush tests and engine tests were performed on real parts manufactured using both processes, confirming the validity and the benefits of this conversion.