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Technical Paper

An Approach to Modeling the Vehicle End-of-Life Process

1998-02-01
980099
A descriptive analysis of the Vehicle End-of-Life (VEOL) process in the U.S. is presented. The material recovery process and the reuse of parts are discussed. A computer VEOL model will be presented which would ultimately be used to analyze the impact of specific regulations, markets factors, and/or business policies, on the recyclability of materials and the reuse of parts. The computer model includes several stages of the VEOL process, including vehicle sales, usage, and retirement; also the dismantling of the retired vehicle, shredding operations, parts and vehicle rebuilders, maintenance and repair. An example of the use of the VEOL computer model on material substitution is presented.
Technical Paper

The Steel Unibody: The Application of Cost Analysis to Determine Cost Reduction Strategies

1998-02-01
981004
Despite repeated challenges from alternative materials and processes, the stamped and spot welded steel unibody remains the near-unanimous choice of automakers for vehicle body-in-white (BIW) structures and exterior panels in volume production. Conventional steel's only weakness is mass; aluminum and polymer composites offer the potential for considerable mass savings, but generally at a higher cost. Efforts within the automakers as well as by outside organizations such as the international steel industry's Ultra Light Steel Auto Body (ULSAB) program are underway to improve the steel uni-body's mass and cost position. To reduce cost, it is first necessary to identify cost. The measurement of cost for a complex system such as an automobile BIW is far from a trivial task. This paper presents an analytical approach to understanding the manufacturing cost for a conventional steel unibody. The results of this cost analysis are then used to outline a strategy for future cost reduction.
Technical Paper

Development of High Toughness Bainitic Microalloyed Forging Steel

1998-02-01
980883
The influence of chemical compositions and forging conditions on mechanical properties of forged bainitic steels were studied. Manganese and chromium are useful to produce bainite structure while carbon and vanadium are good to control the mechanical properties of the steels. One of the compositions is 0.25 % C - 2.1 % Mn - 0.7 % Cr - 0.15 % V of which tensile strength is 1000 MPa and impact value (2 mm U type notched specimen) is 50 J/cm2 for 100 mm diameter bars. Bainitic steels have lower fatigue limit in the case of smooth specimen than ferrite-pearlite microalloyed steels but have higher fatigue limit in the case of notched specimen.
Technical Paper

The Meta VVH System - A Continuously Variable Valve Timing System

1998-02-01
980765
A continuously variable valve timing system called the “Meta VVH System” is presented. It allows the unthrottled load control of spark ignition engines. Two camshafts rotating at the same speed are acting on the intake valve(s) via a follower and a transmission element in such a way, that the output displacement is the sum of the effective displacements of the two cams. The first camshaft which operates as an opening cam is driven directly by the crankshaft. The second camshaft operating as the closing cam is driven by the opening cam via a four wheel gear drive. This gear drive allows a phasing between both camshafts in a range necessary to vary lift and duration of the valve(s) from zero to maximum. This system not only offers the flexibility and range required for an unthrottled load control but also shows benefits concerning its friction losses even in comparison to modern state of the art valve trains like the roller finger follower.
Technical Paper

Developing the Thermoplastic Water Pump and Power Steering Pulley for a Passenger Car

1998-02-01
980736
The thermoplastic automotive pulley has been developed and will be commercialized to high volume production that achieves cost saving and weight reduction over other automotive pulleys in the metal and thermosetting resin by Hyundai Motor Company. Design feature incorporated in this automotive pulley allow it to be manufactured and assembled onto the water pump more efficiently in consequence of design integration with the water pump and power steering pulley. However, the harsh environment and dynamic loads that the thermoplastic pulley has to withstand required extensive CAE analysis and testing of the molded parts and the standard glass reinforced PA was selected for the application to maximize cost savings. The key aspects of the plastic automotive pulley as well as its advantage are presented.
Technical Paper

Inelastic Behavior and Low Cycle Fatigue of Aluminum Alloy Subjected to Thermo-Mechanical Loading

1998-02-01
980688
Many methods for estimating the fatigue life of an aluminum alloy have been proposed in order to save development time and cost as demand for durable and light-weighted material grows strong. None of them, however, are practical enough to estimate the life of an engine component because thermal and mechanical loads on the engine component change as time elapses. Firstly, this paper deals with a method for clarifying the inelastic characteristics of an aluminum alloy, especially the effects of strain amplitude, ductile period (compression-tension cycle time) and temperature range on inelastic deformation, by making experiment where both thermal and mechanical loads were applied in the inverted phase(‘out-of phase’). Secondly the paper discusses a possibility of improving accuracy in determining the fatigue life of the material by introducing a new index of ‘plastic work density per second’, which is based on the conventional concept of plastic strain energy density.
Technical Paper

Friction Induced Paint Damage: An Objective Assessment of Three Coating Systems

1998-02-01
980711
Engineered injection molded thermoplastic polyolefins are now common substrates of choice for painted automotive bumper fascias. A major concern with painted plastics involves susceptibility to surface damage in the shop floor, during transit and in service life. Preliminary failure analysis of field specimens points out the damage in majority of the cases to be “cohesive”, within the near surface regions of the substrate. This paper describes the application of a second-generation computer controlled instrumentation, which simulates Friction Induced Damage (FID) similar to those observed in the field. It has been recognized in several earlier works, that FID is a complex phenomenon and is a function of number of tribological and environmental variables. Since the material systems are viscoelastic, FID is also a strong function of temperature and the dynamic mechanical properties of the coating and substrate.
Technical Paper

Survey of Driver Seating Positions in Relation to the Steering Wheel

1998-02-01
980642
The current study estimates about 5 percent of the U.S. female population sits closer than 10 inches from the steering wheel; 35 percent for the smallest 10 percent of the female population. Of the females sitting closer than 10 inches, 66 percent sit within 9-10 inches, and 17 percent sit within 8-9 inches. In a separate study, drivers sitting within 9-10 inches were able to increase this distance to 10 inches or more and still drive comfortably in a number of cars by making a few minor seating adjustments.
Technical Paper

Contribution to Life Cycle Assessment of Highway Infrastructures

1998-02-01
981153
Assessing the impacts of road infrastructures has always been an environmental, social and economical concern over the last decades, but assessing global impacts over the whole life time of the infrastructure (i.e. considering the traffic emissions over the life time of the infrastructure) has rarely been performed. With the help of the life cycle approach, such a global environmental assessment has been undertaken by the authors (Pereira, Blanc, Coste, 1996). This paper presents the methodological approach, based on Life Cycle Assessment (LCA) and its application to the choice of a highway section among three alternatives. Applying the life cycle assessment methodology (according to the current ISO work undertaken for LCA), the system limits are defined so that the environmental aspects of the infrastructure are addressed from raw acquisition to final disposal.
Technical Paper

Total Cost Analysis of Lead-Free Automotive Electrocoating

1998-02-01
981165
Total cost analysis (TCA) was used to evaluate a pollution prevention project in automotive electrocoating. The objective of TCA was to examine tradeoffs between reduced environmental costs and potentially higher materials costs for a lead-free process. The TCA model considered here is a hybrid of two TCA models, developed separately by P. Bailey and A. White. Results of the analysis show that a lead-free paint price premium of not more than 0.3% over the leaded paint price results in the lead-free project being financially worthwhile. After incorporating liability and less tangible benefits and allowing the savings to be valued at several million dollars over twenty years, the project becomes financially advantageous at the estimated 9% lead-free paint price increase.
Technical Paper

Powertrain and Brake Modeling of the 1994 Ford Taurus for the National Advanced Driving Simulator

1998-02-01
981190
This paper introduces the quasi-static powertrain model for eventual use in the National Advanced Driving Simulator. The 1994 Ford Taurus model is illustrated along with experimental validations; a one-dimensional torque formulation that includes the torque and angular velocity transmitted through the engine, torque converter, automatic transmission gear box, differential, and final drive. A model of the cruise control based on the proportional integrator controller is introduced. The model is able to mimic all basic functions of the speed controller. The load sensitive brake system is modeled with a generic Anti-lock Brake System.
Technical Paper

Combustion Control with the Optical Fibre Fitted Production Spark Plug

1998-02-01
980139
Optical measurement technique became more and more common for the last few years. Especially optical fibre technique is often used to detect flame propagation. With optical sensors the ignition process can be investigated with high temporal and spatial resolution. An in-cylinder optical sensor has been developed and tested to analyze the ignition of mixture and luminous emission of burning gas. The sensor consists of eight optical probes fitted in a conventional spark plug. The results show good correlation between measured luminosity and combustion parameters such as load, engine speed, ignition timing and air-fuel mixture ratio. A correlation between development of light intensity and pressure was found. For evaluation of light signals different analysis methods are presented. Furthermore it is shown that the luminosity of the flame can be used to control the combustion process.
Technical Paper

Methane Jet Penetration in a Direct-Injection Natural Gas Engine

1998-02-01
980143
A direct-injection natural gas (DING) engine was modified for optical access to allow the use of laser diagnostic techniques to measure species concentrations and temperatures within the cylinder. The injection and mixing processes were examined using planar laser-induced fluorescence (PLIF) of acetone-seeded natural gas to obtain qualitative maps of the fuel/air ratio. Initial acetone PLIF images were acquired in a quiescent combustion chamber with the piston locked in a position corresponding to 90° BTDC. A series of single shot images acquired in 0.1 ms intervals was used to measure the progression of one of the fuel jets across the cylinder. Cylinder pressures as high as 2 MPa were used to match the in-cylinder density during injection in a firing engine. Subsequent images were acquired in a motoring engine at 600 rpm with injections starting at 30, 20, and 15° BTDC in 0.5 crank angle degree increments.
Technical Paper

Design of the Fiat Auto Corse ITC 96 Racing Engine - Part I: Valve Lift Profiles and Timings

1998-02-01
980124
The paper describes the fluid dynamic design of the 2.5 liter V6 engine developed by Fiat Auto Corse for the 1996 International Touring Car Series (690 engine). The paper enters into details concerning the definition of valve lift profiles and timings, and provides highlights on the configuration able to optimize the engine in its overall complexity.
Technical Paper

Design of the Fiat Auto Corse ITC 96 Racing Engine - Part II:Pipe Lengths and Diameters

1998-02-01
980125
The paper describes the fluid dynamic design of the 2.5 liter V6 engine (690) developed by Fiat Auto Corse for the 1996 International Touring Car Series. The paper enters into details concerning the definition of pipe lengths and diameters and provides highlights on the configuration able to optimize the engine in its overall complexity.
Technical Paper

Analysis of Synchronous Belt Vibration in Automotive Valve Train

1998-01-29
880077
The synchronous belt employed in the valve train of automotive engines is operated under fluctuating load. Two types of the belt vibration are observed. One is the well-known lateral vibration. The other is the vibration in the belt running direction which may cause the resonant vibration of the camshaft rotation and may affect the belt life. The purpose of this paper is to describe an analysis of the latter vibration. This vibration was analyzed using the model composed of the inertia moment of the camshaft system and the nonlinear elasticity of the belt in the running direction. The predicted resonant frequency and amplitude were in good agreement with the measured ones. The influence of each factor of the model on the vibration was also investigated. The stiffness in the belt running direction that is determined by the tooth distortion When the belt engages with the pUlley should be increased to reduce the amplitudes of the resonant Vibration.
Technical Paper

Modelling and Real-time Simulation of a turbocharger with variable turbine geometry (VTG)

1998-01-23
980770
This paper deals with physical modelling of a turbocharger with variable turbine geometry (VTG) and its real-time simulation based on dynamic artificial neural networks (ANN). Thermodynamic und fluiddynamic equations, describing the basic functionality and relations between pressure, mass flow and temperature at the inlet and outlet ports of compressor and turbine, build up a multiple input multiple output model (MIMO). A special kind of ANN, namely the LoLiMoT algorithm, is used for real-time simulation. Training the network using measurement and simulated data, the dynamic behaviour can be simulated with less computational effort than the physical model. The neural network may be used in engine control systems as observer for non measurable signals, like rotor speed or turbine and compressor torque, figure 1.
Technical Paper

Development of Hardening Penetration Depth Evaluation Using Ultrasonic Wave

1998-01-23
981082
A “Hardening Penetration Depth Evaluation” technique using ultrasonic wave is developed, instead of destructive inspection. An induction hardened structure possesses extremely fine(∼10μm) grain size, whereas, an non-hardened structure possesses coarse(∼100μm) grain size. This non-destructive technique measures scattering echo, scattered from boundary of hardened structure and non-hardened structure. The advantage of this technique is that through the visualization, one can measure scattering echo around the material and thus acquire quenching pattern. In addition throughout its resolution, one can measure scattering probability distribution of the ultrasonic wave and obtain hardening penetration depth.
Technical Paper

Use of Managing Techniques in the development of products in the automotive industry: consequences on quality, cost and time parameters

1997-12-31
973039
International competition, fragmentation of markets with increasingly demanding consumers and novel technologies have strongly contributed to a turbulent and highly competitive scenario of the automobile sector. The characteristics of the market have brought the development of products into the spotlight in this competitive “game”. Companies have started valuing and demanding more of the development of novel products with the aim to obtain high productivity, high quality short term projects. The current work aims to identify the contribution of some management techniques and engineering tools to the improvement of the product development process performance parameters.
Technical Paper

Effects of natural gas composition on bus engine performance

1997-12-31
973038
Aiming at evaluating the effects of natural gas composition on engine operation, the Engine Group of IPT has completed a series of dynamometer tests in a Mercedes Benz M366G gas engine. Twenty-five gaseous fuel compositions, several specially prepared to extend the available CNG compositions, were engine tested. The tests were executed to evaluate performance, exhaust emissions and knock-limited spark timing. The experimental results were correlated with methane and Wobbe numbers calculated from the gas composition. The obtained data corroborate the relevance of these parameters to engine operation. For the tested engine, that uses an open loop fuel system, the data indicate the need to maintain the natural gas specifications in narrow limits if one wants to explore the natural gas low pollutant potential. This study has subsidized the elaboration of a Brazilian vehicular natural gas specification.
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