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Back to the non Flex Fuel vehicles, the knock control system was designed and calibrated to absorb differences between engines (mainly compression ratio) and to protect the engine against knock damage (a correction up to 4 degrees BTDC was usually enough). But now, two new variables get in the scene: Flexible Fuel strategy, working from E22 to E100 (all blends in between) and small displacement (1.0 liter) high compression ratio engines. In this new scenario the system must be capable of correcting all spark advance differences, once knock control system acts as a safety feature, protecting the engine even if the fuel learning shows some deviation. In addition to that, we have the compression ratio variation between minimum and maximum limits. Since the engine is small (as well its combustion chamber), each tenth of a millimeter difference during manufacturing process, results in an important final compression ratio variation.

In the engine management systems field, there is lack of sensors locally built and available for sale in Brazil. Therefore, many auto parts companies have to import them affecting directly the final products costs (technology know-how/development costs, import taxes and other material handling/custom related costs). This paper was motivated to study an alternative for a simple, cheaper and locally made throttle position sensor. The choose of this part was because the fact that it is one of the most expensive in the throttle body bill of. For developing this new alternative, it was used a tool called value analysis and value engineering. The outcome of this study was a throttle position sensor function integrated to the throttle body manufacturing line with the advantages that 100% components can be locally purchased, improved robustness against humidity and component quantity reduction by 40%. Therefore achieving more value added.

The penetration of rainwater through the heating ventilation and air conditioning system (HVAC) of a vehicle directly affects the provision of thermal comfort within the vehicle passenger compartment. Present vehicle designs restrict considerably the air-management processes due to reduced space and tighter packaging. The motivation for the study is to get an insight into factors affecting the water ingress phenomenon when a stationary vehicle is subjected to water loading such as heavy rain when parked or waiting in a traffic light or when in a car wash. The test programme made use of a compact closed circuit full-scale automotive climatic wind tunnel that is able to simulate wind, rain and road inclination. The tunnel was developed as part of the collaborative research between the Flow Diagnostics Laboratory (FDL) of the University of Nottingham and Visteon Climate Control Systems [1].

The drive to reduce weight, simplify assembly, and cut total system cost in today's vehicles is relentless. Replacing metal systems with thermoplastics has been of considerable interest in the engineering community. The current generations of engineering thermoplastic resins are enabling the use of plastic systems in demanding underhood applications. Technical data and discussion regarding the materials, design, molding, and assembly of lightweight composite throttle bodies will be presented in this paper. Comparisons with machined aluminum throttle housings are drawn to establish a baseline with the throttle body housing component that is most common in production today. Design flexibility and process simplification are some of the approaches highlighted. Much of the technical information provided in the paper applies to both cable driven mechanical throttle bodies as well as electronic throttle bodies under development.

For the past decade or so, automotive entertainment subsystem architectures have consisted of a simple Human Machine Interface (HMI), AM-FM tuner, a tape deck, an amplifier and a set of speakers. Over time, as customer demand for more entertainment features increased, automotive entertainment integrators made room for new features by allowing for the vertical integration of analog audio and adding a digital control. The new digital control came to entertainment subsystems via a low-speed multiplexing scheme embedded into the entertainment subsystem components, allowing remote control of these new features. New features were typically incorporated into the entertainment subsystem by independently packaging functional modules. Examples of these modules are cellular telephone, Compact Disc Jockey (CDJ), rear-seat entertainment, Satellite Digital Audio Radio System (S-DARS) receiver, voice and navigation with its associated display and hardware.

High-dilution stratified EGR combustion system operating at stoichiometric air-fuel ratio (A/F) could offer significant fuel economy saving comparable to the lean burn or stratified charge direct injection SI engines, while still complies with stringent emission standards by using the conventional three-way catalytic converter. The most critical challenge is to keep substantial separation between EGR gas and air-fuel mixture, or to minimize the mixing between these two zones to an acceptable level for stable and complete combustion. Swirl-type stratified EGR and air-fuel flow structure is considered desirable for this purpose, because the circular engine cylinder tends to preserve the swirl motion and the axial piston movement has minimal effect on the flow structure swirling about the same axis. In this study, KIVA3V was used to simulate mixing and combustion processes in a typical pent-roof gasoline engine cylinder during compression and expansion strokes.

An accelerated seat durability test was developed to identify potential problems in areas with traditionally high warranty cost and customer dissatisfaction: squeak & rattle and mechanism looseness & efforts. The test inputs include temperature, humidity, road vibration, occupant movements, and mechanism cycling. These inputs were combined into a single 14-day test profile that simulates 10 years and 250,000 km. (approximately 150,000 miles) of 95th percentile customer usage. Various components of the seat assembly are tested together as a system. The test was performed on two current production programs. The test produced issues similar to those found in warranty repair data and evaluations of used seats from high-mileage customer-owned vehicles.

A low-pressure CO2-based climate-control system has the environmental benefits of CO2 refrigerant but avoids the extremely high pressures of the transcritical CO2 cycle. In the new cycle, a liquid “cofluid” is circulated in tandem with the CO2, with absorption and desorption of CO2 from solution replacing condensation/gas cooling and evaporation of pure CO2. This work compares the theoretical performance of the cycle using two candidate cofluids: N-methyl-2-pyrrolidone and acetone. The optimal coefficient of performance (COP) and refrigeration capacity are discussed in terms of characteristics of the CO2-cofluid mixture. Thermodynamic functions are determined either from an activity coefficient model or using the Soave equation of state, with close agreement between the two approaches. Reductions in COP due to nonideal compressor and heat exchangers are also estimated.

Environmental concerns have spawned renewed interest in naturally occurring refrigerants such as carbon dioxide. CO2 has attractive features such as high enthalpy of evaporation and low cost compared to halocarbons. However, the vapor pressure of CO2 is high at temperatures normally encountered in refrigeration and air conditioning systems when compared to traditional and alternative refrigerants such as CFC-12 and HFC-134a. Major research efforts are underway to investigate the transcritical CO2 cycle, in which a gas cooler instead of a condenser accomplishes heat rejection to ambient, since carbon dioxide in this cycle is above the critical point. The vapor pressure in the gas cooler may exceed 120 bar (1,740 lb/in2). In this paper a reduced pressure carbon dioxide system is revisited1, 2. The working fluid is a mixture of CO2 and a non-volatile liquid, referred to as a co-fluid, in which CO2 is highly soluble and readily absorbed and desorbed.

Pressures to increase the recyclable and recycled content of passenger vehicles are accelerating. In Europe, there is interest in eliminating halogenated polymers. Globally, more and more concern is focused on materials and methods that are ecologically friendly. Automakers and their suppliers are being encouraged to design and assemble components in new ways to facilitate separation, identification, and resource recovery at the end of the vehicle’s useful life - something that is not only good for the environment, but also the bottom line. One area of the vehicle that has proved challenging for applying such design for disassembly and recycling (DFD/R) principles has been the interior, owing to the sheer number of materials used there, and the great number of laminate structures that make disassembly nearly impossible. A good example is a door panel inner, which typically consists of a rigid plastic substrate, a foam pad, and a vinyl, leather, or cloth covering.

A design framework based on the principles of lean manufacturing and axiomatic design was used as a guideline for designing an automotive component manufacturing system. A brief overview of this design decomposition is given to review its structure and usefulness. Examples are examined to demonstrate how this design framework was applied to the design of a gear manufacturing system. These examples demonstrate the impact that low-level design decisions can have on high-level system objectives and the need for a systems-thinking approach in manufacturing system design. Results are presented to show the estimated performance improvements resulting from the new system design.

Plastics manufacturing technology is rapidly changing. The use of process simulation to increase competitiveness has proliferated. Visteon Automotive Systems is committed to developing competent workforce and niche capabilities in plastics processing simulation. In this paper the current capabilities and future development plan for plastic process simulation are discussed. An integrated concurrent engineering process has been developed and implemented to deliver high quality robust plastics automotive products and systems. This paper highlights the technological advancements achieved by Visteon in the field of analytical simulation of common manufacturing processes. In addition, future development initiatives towards the technical competency in plastics manufacturing simulation are discussed throughout the manuscript.

In a joint effort between Ford Motor Company, Visteon Automotive Systems, Textron Automotive Company, and Dow Automotive the 1999 Mercury Cougar instrument panel (IP) was designed and engineered to reduce the weight and overall cost of the IP system. The original IP architecture changed from a traditional design that relied heavily upon the steel structure to absorb and dissipate unbelted occupant energy during frontal collisions to a hybrid design that utilizes both plastic and steel to manage energy. This design approach further reduced IP system weight by 1.88 Kg and yielded significant system cost savings. The hybrid instrument panel architecture in the Cougar utilizes a steel cross car beam coupled to steel energy absorbing brackets and a ductile thermoplastic substrate. The glove box assembly and the driver knee bolster are double shell injection molded structures that incorporate molded-in ribs for added stiffness.

Carbon dioxide (CO2)-based refrigeration systems have been proposed as environmentally benign alternatives to current automotive air conditioners. The CO2 vapor-compression system requires very high operating pressures and complicated control strategies. Recent experimental results indicate that operating pressures comparable to those of current automotive air conditioners can be attained by the inclusion of a secondary carrier fluid (a “co-fluid”), with solution and desolution of the CO2 from the co-fluid substituting for condensation and vaporization of pure CO2. In this work, modeling tools have been developed to optimize the CO2/co-fluid cycle, including the selection of a co-fluid, the CO2/co-fluid ratio (the “loading”), and the operating conditions.

Environmental concerns have spawned renewed interest in naturally occurring refrigerants such as carbon dioxide. CO2 has attractive features such as high enthalpy of evaporation and low cost compared to halocarbons. However, the vapor pressure of CO2 is high at temperatures normally encountered in refrigeration and air conditioning systems when compared to traditional and alternative refrigerants such as CFC-12 and HFC-134a. Major research efforts are underway to investigate the transcritical CO2 cycle, in which a gas cooler instead of a condenser accomplishes heat rejection to ambient, since carbon dioxide under these conditions is above the critical point. The vapor pressure in the gas cooler may exceed 120 bar (1,740 lb/in2). In this paper a reduced pressure carbon dioxide system is reported (Ref 1). Two companion papers will address properties of working fluids (Ref 2) and thermodynamic and cycle models (Ref 3) for the low pressure carbon dioxide cycle.

Fuel Vapor Storage Systems (FVSS) on automobiles are susceptible to particle contamination. This is especially true for FVSS components mounted under the automobiles (undercarriage, chassis frame, etc.) and required to meet stringent EPA standards. Particle contamination significantly increases system restriction and reduces the effectiveness of FVSS. This paper describes a dust separator/filter developed to protect the FVSS. Accelerated field durability evaluations and measurement techniques were developed to identify clean locations, ingested contamination levels and ingested contaminant size distributions. Based on field evaluations, test methods were developed in the lab to evaluate effectiveness of several devices to control and reduce contamination. The dust separator design developed was a combination of baffle separators in series with an open cell foam filter. The dust separator was designed to meet and exceed several vehicle system design requirements.

This paper highlights the application of design optimization in reducing product manufacturing cost without compromising product performance. By using a topology optimization method, the manufacturing cost of a clam shell has been reduced by approximately one-third, while maintaining the NVH performance of the steering column that is connected to the instrument panel (IP) through the clam shell. Two different optimization approaches and two different topological weld deployments are investigated. It is found that a fully-deployed seam weld approach with automatic optimization provides the best design results.

This paper reviews the physics-of-failure model for accelerated thermal cycle tests of solder joints associated with various electronics components, summarizes the parameters of the automotive environment, and discusses the methods for developing thermal cycle tests for reliability validation for automotive electronics. The paper proposes an approach to develop the requirements for validation tests based on the customer usage profiles and the desired product life goal. This requirement determines the nominal testing duration based on the equivalent damage generated from the worst-case field applications.

A compact cassette and compact disc (CD) mechanism mounting bracket was developed for an automotive radio. The bracket, a single die cast magnesium component, offers a light weight, rigid platform for simultaneously attaching both mechanisms to create a simple modular subassembly.

The scratch resistance of automotive plastic coatings has been studied extensively over the past few years. Most testing methodology to correlate damage of the coating to field conditions has been in the form of small particulate wearing, e.g., alumina oxide abrasive, or indentation resistance of the coating to an external probe, e.g., a nanoindentation device. The subsequent damage imparted to the coating has generally been analyzed by the amount of coating mass lost in the wear event or through a ratio of optical reflectance of the damaged area to the undamaged surface. In this paper, we attempt to delineate surface damage resistance of several automotive clearcoats through an optical interferometry methodology developed to measure volume and depth of damage incurred with small particle alumina oxide erodents in a simulated wear environment.