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As global automobile manufacturers prepare for the phase-out of R134a in Europe, they must address the issue of using the new refrigerant for European sales only or launching the product worldwide. Several factors play into this decision, including cost, service, risk, customer satisfaction, capacity, efficiency, etc. This research effort addresses the minimal vehicle-level hardware differences necessary to provide a European solution of R1234yf while continuing to install R134a into vehicles for the rest of the world. It is anticipated that the same compressor, lubricant and condenser; most fluid transport lines; and in most cases the evaporator can be common between the two systems.

The automotive aftermarket represents a challenge for supply chain management when compared to traditional practices in the original equipment manufacturer (OEM) supply chain. This paper presents a case study for a Tier One automotive supplier’s challenges with inventory carrying costs, backorder risk, and supplier relationships for a rear seat entertainment system in the automotive aftermarket. It will also address the lean principles used to improve the business and increase material planning analyst productivity. A call for OEMs to examine their business practices is also included.

In this paper, an analytical procedure for prediction of shell radiated noise of air induction systems (AIS) due to engine acoustic excitation, without a prototype and physical measurement, is presented. A set of modeling and simulation techniques are introduced to address the challenges to the analytical radiated noise prediction of AIS products. A filter seal model is developed to simulate the unique nonlinear stiffness and damping properties of air cleaner boxes. A finite element model (FEM) of the AIS assembly is established by incorporating the AIS structure, the proposed filter seal model and its acoustic cavity model. The coupled acoustic-structural FEM of the AIS assembly is then employed to compute the velocity frequency response of the AIS structure with respect to the air-borne acoustic excitations.

First LED headlamps will be released into the market in 2007. Special permissions allow this introduction although the official regulation is still under discussion in ECE. The LED technology for front lighting has entered into a new phase from theoretical, prototype status to real and practical applications. Additionally in Europe the legislation, which is under preparation, defines LED modules with one or more LED chips in a row which should be replaceable. With this boundary conditions headlamp suppliers needs to balance between an attractive and innovative styling, demanded by car manufacturers and the light performance to gurantee good visibility at night. The paper describes the methods how to design an LED headlamp with high efficiency by keeping in mind the parameters: packaging, weight, styling and light perfromance. Results with specific design proposals are shown.

This paper describes a front road wheel steer-by-wire system with two actuator motors on the rack and pinion assembly to move the road wheels. Dual actuators are used to provide actuator redundancy and to enhance the fault tolerance capability. When one actuator faults or fails, the other actuator is designed to work independently and maintain full system performance. The paper emphasizes control method to implement the motion control for the front road wheel steer-by-wire system with two actuators on the common load. The proposed dual servo synchronization motion control implements the angle tracking for the road wheel reference input by controlling two actuators synchronously and cooperatively. It includes two servo feedback control loops to track the common reference input. The angular position error between two feedback loops is compensated using a synchronized compensator.

During last 10-15 years we could have seen quite big changes in automotive lighting. The most important changes are: a) plastic materials mostly removed metal and glass material from lighting products raised heat issue of plastics materials b) escalation of competition between lighting suppliers (globalization, merging, …) decrease of time and cost for development of the new product as much as possible

High-power LEDs and LED headlamps have become a serious consideration for the automotive industry. White LEDs have achieved the required performance for initial automotive headlamp applications. However tradeoffs among several attributes such as efficiency, cost, weight and performance profoundly affect LED headlamp development and need to be addressed by vehicle manufacturers, lamp set makers and LED source suppliers in order for LED headlamps to be effective. The solutions to these tradeoffs relates to the behavior of the LED sources, the thermo-mechanical integration of LEDs in a headlamp environment and input from the vehicle manufacturer regarding styling and packaging for an LED headlamp on the respective targeted vehicles.

Virtual design validation of an air induction system (AIS) requires a proper finite element (FE) assembly model for various simulation based design tasks. The effect of the urethane air filter seal within an AIS assembly, however, still poses a technical challenge to the modeling of structural dynamic behaviors of the AIS product. In this paper, a filter seal model and its modeling approach for AIS assemblies are introduced, by utilizing the feature finite elements and empiric test data. A bushing element is used to model the unique nonlinear stiffness and damping properties of the urethane seal, as a function of seal orientation, preloading, temperature and excitation frequency, which are quantified based on the test data and empiric formula. Point mobility is used to character dynamic behaviors of an AIS structure under given loadings, as a transfer function in frequency domain.

Modern automobiles utilize stabilizer bars to increase vehicle roll stiffness. Stabilizer bars are laterally mounted torsional springs which resist vertical displacement of the wheels relative to one another. A stabilizer bar is constructed in such a way that it will meet package constraints and fatigue requirements. In order to design a robust stabilizer bar, Taguchi's “Design of Experiment method” is used. The objective of this paper is to develop a robust stabilizer bar design that will maximize the fatigue life and the roll stiffness while minimizing weight. This study is based on results obtained by CAE analysis.

Plastic air induction system (AIS) has been widely used in vehicle powertrain applications for reduced weight, cost, and improved engine performance. Physical design validation (DV) tests of an AIS, as to meet durability and reliability requirements, are usually conducted by employing the frequency domain vibration tests, either sine sweep or random vibration excitations, with a temperature cycling range typically from -40°C to 120°C. It is well known that under high vibration loading and large temperature range, the plastic components of the AIS demonstrate much higher nonlinear response behaviors as compared with metal products. In order to implement a virtual test for plastic AIS products, a practical procedure to model a nonlinear system and to simulate the frequency response of the system, is crucial. The challenge is to model the plastic AIS assembly as a function of loads and temperatures, and to evaluate the dynamic response and fatigue life in frequency domain as well.

Evaporators for automotive air-conditioning systems are being coated externally to improve corrosion resistance, water drainage, and reduce potential odor concerns. The coating durability and efficiency in achieving its corrosion resistance depends on the coating uniformity and adhesion characteristics. Good coating adhesion on aluminum surface can be achieved after freeing the surface from the oxide and flux residues. Evaporators manufactured by the Controlled Atmosphere Brazing (CAB) process have flux residue remaining on the surface, the presence of which interferes with the coating process and also affects the performance of coated components. A methodology to quantify the effect of high Nocolok flux residue on heat exchanger coating uniformity has been presented.

Welding is one of the most commonly used fabrication method in various automotive applications. Welding is a metallurgical fusion process in which parts or work pieces to be joined are heated above their melting temperature and then solidified. Some of the effects of the welding include residual stresses and Heat Affected Zone (HAZ). A methodology is proposed to study the welding process using the commercial finite element software, ABAQUS. Non linear transient heat transfer analysis is used. Effects of heat energy input rate and heat input time on residual stresses and HAZ are determined.

Three dimensional acoustic entertainment enables the listener to experience sounds emanating from all around them, rather than being limited to the space between a pair of stereo speakers. It provides the artist with an enhanced sonic pallet to place sound sources in three dimensional space, as well as potential for a more realistic music reproduction experience. With the popularity of the Digital Versatile Disc (DVD), the technology successfully migrated from the movie theater into the “home theater”. The multichannel replacements for the audio CD (DVD-Audio and Super Audio CD) are enhancing the advancement into the automotive space. Automotive interiors are readymade for multichannel reproduction, but the automotive environment offers some challenges as well. This paper will discuss the market and technical potential for automotive applications of three dimensional sound, matters to take into account, media choices, distribution considerations and a look toward the future.

The increasing power requirement for automotive electronics (radios, etc.), combined with ever-shrinking size and weight allowances, is creating a greater need for optimization and robust design of heat sinks. Not only does a heat sink directly affect the overall performance and reliability of a specific electronics application, but a well-designed, optimized heat sink can have other benefits - such as eliminating the requirement for special fans, reducing weight of the application, eliminating additional heat sink support structures, etc. Optimizing heat sink efficiency and thermal performance offers a challenge, due to the many competing design requirements. These requirements include effecting greater temperature reductions, accommodating vehicle packaging requirements and size limitations, generating a uniform heat distribution, etc., and all the while reducing the heat sink cost.

There are many opportunities in a current automotive HVAC case for improved performance, and cost savings. Based on these opportunities, a new HVAC case design has been developed. This new design is smaller and lighter than current cases while meeting many of the performance requirements. The case also features a unique plenum design for air distribution to the three modes, panel, floor, and defrost. The results of simulation and laboratory testing confirmed the concept of the new HVAC design.

In Brazil the market for plastic parts molds, in last few years had become very competitive, with several Vehicle Operations and a big number of a different models, and with today total market volume it means low volumes productions for each model. This market demands for good toolshops and at the same time a big pressure to reduce investments, one of the most important. Plastic components usage in the car, is increasing overtime, with new applications for Exterior, interior and powertrain, requiring new technologies for Injection molding processing and making molds to be more complex. The development of plastic parts in Brazil has its own characteristics, strengths and weaknesses. In fact a big and heterogeneous market. This paper intends to present an analysis of development of plastic parts in Brazil, considering the development of mold tooling locally, focusing the automotive market.

Analytical methods are used extensively in the automotive industry to validate the feasibility of component and assembly designs and their dynamic behavior. Correlation of analytical models with test data is an important step in this process. This paper discusses the Finite Element model of an innovative Slip-in-Tube Propshaft design. The Slip-in-Tube joint (slip joint) poses challenges for its dynamic simulation. This paper discusses the methods of simulating the joint and correlating it to experimental results. Also, the Noise and Vibration (NVH) characteristics of the Slip-in-Tube Propshaft design. In this paper, a Finite Element model of the proposed propshaft is developed using shell and beam element formulations. Each model is verified to optimize the feasibility of using accurate and computationally efficient elements for the dynamic analysis.

The present work demonstrates the application of Design of Experiments (DOE) statistical methods to the design and optimization of a hydraulic steering pump for NVH performance. DOE methods were applied to RPM-domain data to examine the effect of several different factors, as well as the interactions between these factors, on pump NVH. Whereas most DOE analyses typically consider only a single response variable, the present work considered multiple response variables. Specifically, pump NVH performance curves for several pump rotational orders over a range of shaft speeds were analyzed. Thus, it was possible to determine the effect of the factors in question over the entire speed range of pump operation, rather than a single speed or setting. Statistical methods were applied to determine which factors and interactions had a significant effect on pump NVH. These factors were used to construct an empirical mathematical prediction model for NVH performance.

Application of Ultra Thin Wall (UTW) ceramic substrates in the catalytic converter system requires the canner and component manufacturers to better understand the root cause and physics behind substrate breakage during the canning process. For this purpose, a ceramic substrate strength study for shoebox design has been conducted within Visteon Corporation. Computer Numerical Control (CNC) machined top and bottom fixtures, with identical inner surfaces as shoebox converter upper and lower shells, were used to crush mat wrapped substrates. Thin film pressure sensor technology enables the recording of substrate surface pressure during the compression process. Shell rib, washcoat, canning speed and cell density effects on substrate failure have been experimentally investigated. The development of a mathematical model helps to identify a better indicator to evaluate the substrate strength in the canning process and establish the strength for uncoated & coated substrates.

Visteon has developed a CAE procedure to qualify plastic door trim assemblies under the vehicle door slam Key Life Test (KLT) environments. The CAE Virtual Door Slam Test (VDST) procedure simulates the environment of a whole door structural assembly, as a hinged in-vehicle door slam configuration. It predicts the durability life of a plastic door trim sub-assembly, in terms of the number of slam cycles, based on the simulated stresses and plastic material fatigue damage model, at each critical location. The basic theory, FEA methods and techniques employed by the VDST procedure are briefly described in this paper. Door trim project examples are presented to illustrate the practical applications and their results, as well as the correlation with the physical door slam KLTs.