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The design of the newly developed Toyota AZ series 4 cylinder engine has been optimized through both simulations and experiments to improve heat transfer, cooling water flow, vibration noise and other characteristics. The AZ engine was developed to achieve good power performance and significantly reduced vibration noise. The new engine meets the LEV regulations due to the improved combustion and optimized exhaust gas flow. A major reduction in friction has resulted in a significant improvement in fuel economy compared with conventional models. It also pioneered a newly developed resin gear drive balance shaft.

This paper describes a study of visual responses to center high mounted stop lamps (CHMSLs) using a newly developed sweeping neon lamp. This study compares sweeping neon, incandescent, and light-emitting diode (LED) technologies. The incandescent CHMSL was a conventional after-market CHMSL brake light. The sweeping neon CHMSL used a novel controller whereby the luminous signal started at the center of the neon tube and grew in a “sweeping” motion outward toward the ends of the tube at an adjustable rate. The sweeping LED CHMSL had a segmented display simulating the sweeping characteristics of the neon CHMSL. Both the neon and LED CHMSLs had faster onset times than the incandescent CHMSL. Experimental subjects performed a tracking task cognitively similar to driving, and released a flip switch upon detecting the onset of the CHMSLs, which were mounted so as to be seen peripherally.

This paper will describe the BorgWarner Interactive Torque Management (ITM) system for FWD based AWD systems as well as the utilization of P/M technology for critical components within this system. The ITM is an electro-mechanical coupling device. The device consists of an electromagnet, ball ramp and wet clutch system. The system can be mounted anywhere in the drive line as well as integrated into components such as transfer cases and transaxles. The clutch actuation force is dependent on the current applied to the electromagnetic coil, providing a truly variable torque transfer device. The decision to make extensive use of P/M technology in the structural portion of this system was based on the net shape capability and weight reduction combined with the ability to chose from a wide range of engineered materials that resulted in the most economical total system package.

This paper introduces the new 1.6L engine family, designed and developed by the Chrysler group of DaimlerChrysler Corporation in cooperation with BMW. An overview of the engine's design features is provided, with a detailed review of the performance development process with emphasis on airflow, combustion, thermal management and friction. This information is presented, to provide an understanding of how the engine simultaneously achieves outstanding levels of torque, power, fuel consumption, emissions and idle stability. The use of analytical tools such as Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) in the optimization of the engine is shown.

A new CAD-based model of the occupant/driver for interior and seat design has been developed. Unlike traditional automotive iterative design methods that begin with a 2D human manikin in an environment based on the location of H-point, the 3D ERL manikins determine the initial design positions of multiple occupants based on the simulated interactions of seat, driver package, skeletal linkage system and deflected human tissue. The 3D ERL human body representations come from measurements of posture-critical skeletal landmarks on 102 test subjects combined with measurements of “deflected human tissue” data from 60 test subjects. The result is a set of three dimensional, posture-biofidelic manikins that a computer algorithm optimizes the driver's workplace environment to fit the population range of sizes and postural preferences.

Due to the wide and ever increasing application of thermoplastics for the transportation and automotive industries, the performance of the under-the-hood plastic parts depend upon optimized design and processing technology and properties of polymer based materials. Nylon (polyamide) based plastics are used widely for automotive cooling fans and various under-the-hood injection molded components. For injection molding of multi-blade cooling fans and various rotating plastic parts the complex of multiple gating injection molding tools were used. Both the design of the various rotating parts (including industrial and automotive cooling fan, and the molding tool design are very important to get optimum flow patterns and to predict the locations and interaction of stress-bearing areas and knit lines (planes or inter-phases)1. The mechanical performance of the injection-molded thermoplastic components depends on the peculiarity of the part and the molding tool design.

Engineering thermoplastics were successfully utilized in the design of injection molded rotating parts such as the impellers, wheels, and cooling fans of commercial air-cooled chillers, and gas and diesel engines. Complex aerodynamic and mechanical performance of impellers and cooling fans are very important for the efficiency of integrated air-movement, climate control and cooling systems of various types of engines of vehicles, cars, heavy-duty tractors and trucks. The transportation and automotive industries have developed a culture of reliability and cost effectiveness, in which high risks and adventures are not encouraged. Due to the wide and ever increasing application of thermoplastics for the transportation and automotive industries, the performance of the under-the-hood parts depend upon optimized design and processing technology and properties of polymer based materials.

A comparative study of the mechanical performance of welded polyamide joints is evaluated. Under optimized welding (linear and orbital vibration, hot plate, transmission laser) conditions, the tensile strength of welded polyamide/nylon (filled and fiber-reinforced) is close or slightly higher (up to 14%) than the tensile strength of the base polymer (non-filled polyamide). In this study, the influence of two important effects (local reinforcement and “memory”) on the mechanical performance of polyamide/nylon welds is analyzed and discussed. The results presented in this study will help plastic part designers, material developers and manufacturers, choose optimized welding conditions for polyamide/nylon parts in a wide range of industrial applications.

Beside the traditional prediction of stresses and verification by mechanical testing the optimization of cylinder liner bore distortion is one of today's most important topics in crankcase structure development. Low bore distortion opens up potentials for optimizing the piston group. As the piston rings achieve better sealing characteristics in a low deformation cylinder liner, oil consumption and blow-by are reduced. For unchanged oil consumption and blow-by demands, engine friction and subsequently, fuel consumption could be reduced by decreasing the pre-tension of the piston rings. From the acoustical point of view an optimization of piston-slap noise is often based on an optimized bore distortion behavior. Apart from basics to the behavior of liner bore distortion the paper presents advanced analytical and empirical methods for detailed prediction, verification and optimization of bore distortion taking into account the effective engine operation conditions.

Today, a number of simulation codes are available for pre-designing gas exchange systems of IC engines with good accuracy (e.g. PROMO, WAVE, GT-Power). However, optimizing such systems still requires numerous time consuming and inefficient trial and error runs. Also, accounting for constraints as size, volume, peak combustion pressure etc. multiplies the necessary efforts additionally. Hence there is a strong need for efficient procedures for finding optimum designs automatically and reliably. To automatically find the global optimum design parameters under a given set of real constraints of a practical case, a multi-membered evolution-strategy based optimization code was developed. The code which efficiently finds the true optimum dimensions of gas exchange systems (duct lengths, duct diameters, volumes) of an IC engine. The code can be readily generalized, and adapted to arbitrary optimization problems.

Coming along with the present movement towards the ultimately variable engine, the need for clear and simple models for complex engine systems is rapidly increasing. In this context Common-Rail-Systems cause a special kind of problem due to of the high amount of parameters which cannot be taken into consideration with simple map-based models. For this reason models with a higher amount of complexity are necessary to realize a representative behavior of the simulation. The high computational time of the simulation, which is caused by the increased complexity, makes it nearly impossible to implement this type of model in software in closed loop applications or simulations for control purposes. In this paper a method for decreasing the complexity and accelerating the computing time of automotive engine models is being evaluated which uses an optimized method for each stage of the diesel engine process.

An electromechanically driven valve train offers unprecedented flexibility to optimize engine operation for each speed load point individually. One of the main benefits is the increased fuel economy resulting from unthrottled operation. The absence of a restriction at the entrance of the intake manifold leads to wave propagation in the intake system and makes a direct measurement of air flow with a hot wire air meter unreliable. To deliver the right amount of fuel for a desired air-fuel ratio, we therefore need an open loop estimate of the air flow based on measureable or commanded signals or quantities. This paper investigates various expressions for air charge in camless engines based on quasi-static assumptions for heat transfer and pressure.

This paper presents the experimental work and the results obtained from the implementation of a transient fuel compensation algorithm for the 6.0-liter V12 high-performance engine that equips the Lamborghini Diablo vehicles. This activity has been carried out as part of an effort aimed at the optimization of the entire fuel injection control system. In the first part of the paper the tests for fuel film compensator identification are presented and discussed. In this phase the experimental work has been conducted in the test cell. An automatic calibration algorithm was developed to identify the well-known fuel film model X and τ parameters, so as to define their maps as a function of engine speed and intake manifold pressure. The influence of engine coolant temperature has been investigated separately; it will be soon presented together with the air dynamics compensation algorithm. In the second part of the paper, the performance of the fuel dynamics compensation algorithm is analyzed.

The alleviation of environmental problems associated with personal, public and commercial transport in urban areas has become an important issue for both policy makers and the automotive industry. Future legislation in Europe and the USA is expected to introduce strict limits in vehicle emissions, and both electric and hybrid vehicles are considered to be strong contenders for meeting low / zero emissions targets. As a result, research into electrically driven powertrains, which have similar performance attributes as ICE (Internal Combustion Engine) vehicles, has led to the development of electrically actuated wheel technologies, with increasing attention being focused on research into novel antilock braking / traction control (ABS / TCS) strategies. This paper describes a comparison of traction control schemes using real - time observer based estimates of μ-slip characteristics.

The classical theory of wind tunnel corrections calculated from potential flow theory is revisited. In this context a flow model uniformly valid for all types of test sections is developed for the correction of drag in automotive wind tunnels. To define and size the singularities setting up the flow model only geometrical properties of the model and measured force coefficients will be used. To achieve a correct representation of the flow about a vehicle body a number of improvements to the classical approach are proposed. Based on the uniformly valid flow model, correction formulae for closed wall, open jet and slotted wall test sections are given. For the open jet and slotted wall case it is shown, that the presented formulae are still incomplete, whereas for the closed wall case the correction is ready to use. The correction approach is validated step by step by comparison with appropriate experimental data.

A case study of the application of shape optimization techniques to reduce the weight of a steering knuckle of a heavy truck suspension has been presented. Design analysts, who work with finite element shape optimization, face a daunting task while handling such complicated parts - uneven shape, multiple load cases and element distortions during shape optimization, etc. A baseline analysis confirmed that the knuckle was overweight. A shape optimization analysis was undertaken to bring down its weight and at the same time keep the stresses within design limits. A numerical interpolation method has been used to generate shape vectors. The weight of the knuckle was brought down by 12.7% and the final design was verified using II order solid finite elements.

Using a finite element approach, a technique for optimization of an exhaust system design was developed. This technique involved the creation of the parameterized model, implementation of the loading and finally the optimization of the model. In the creation of the finite element model, pipe elements were used. Parameters were assigned to the structure using coordinate relations between nodes, instead of the positions of the nodes in coordinate space. The model was then verified using modal analysis. A random vibration analysis was used as a loading criterion for the model, as well as static gravitational loading. The optimization of the design focused primarily on the shape characteristics of the structure and secondarily on each component thickness. Using only thickness parameters, a 15% reduction of the weight of the system was achieved, with an additional 2-3% decrease in weight possible through shape optimization.

With the revolutionary advances in computing power and software technology, the future trend of integrating design and CFD analysis software package to realize an automated design optimization has been explored in this study. The integrated process of UG, ICEMCFD, and FLUENT was accomplished using iSIGHT for vehicle Aero/Thermal applications. Process integration, CFD solution strategy, optimization algorithm and the practicality for real world problem of this process have been studied, and will be discussed in this paper. As an example of this application, the results of an underhood thermal design will be presented. The advantage of systematical and rapid design exploration is demonstrated by using this integrated process. It also shows the great potential of computer based design automation in vehicle Aero/Thermal development.

This paper describes a method to account for the effects of induction hardening in computer simulation of automotive parts. This method, which is currently being used at PSA Peugeot-Citroën, enables the rapid optimization of shapes and heat treatments (usually for weight reduction purposes). It is a two-stage method. The first stage is based on simple topological geometries accounting for the heat treatment, which are implemented directly in the finite element model Abaqus®. This first stage allows for a succession of quick iterations. The second stage of the method consists of linking the various relevant process simulation softwares (Forge3®, Sysweld®, etc.) and Abaqus®, in order to confirm the optimized shape and treatment obtained in the first stage. Simulation of transmission auto parts will be presented as illustrations of this method.

Today, Computer Aided Engineering (CAE) is a feature that becomes more and more essential in the development of Thermal-Acoustical Protective Shields (TAPS). The development cycle of TAPS needs to be reduced while simultaneously reducing costs. The performance, functionality and visual appearance need to be improved as well. This paper will describe our general CAE approach, which is based on the use of different CAD systems and Finite Element Analysis (FEA). We will describe how we use the results of our approach in the development of new TAPS. Because this approach is based on the knowledge of the parameters that exist and how they influence a TAPS function, we will first discuss the most important of these parameters. Here we split our discussion into ‘What is a TAPS, ‘What are the main steps of making a TAPS - Designing, prototype’, and ‘How a TAPS works in an engine’. We will then explain the different FEA utilization's.