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Main topics are the development and the build-up of an 18ton hybrid truck with a parallel hybrid drivetrain. With this truck it is possible to drive up to 3 kilometers in the pure electric driving mode. Presenter Andreas Eglseer, Engineering Center Steyr GmbH & Co. KG

Ethanol for use in automotive fuels can be made from renewable feedstocks, which contributes to its increased use in recent years. There are many differences in physical and chemical properties between ethanol and petrochemicals refined from fossil oil. One of the differences is its energy content. The energy content, or heating value, is an important property of motor fuel, since it directly affects vehicle fuel economy. While the energy content can be measured by combustion of the fuel in a bomb, the test is time-consuming and expensive. It is generally satisfactory and more convenient to estimate that property from other commonly-measured fuel properties. Several standardized empirical methods have been developed in the past for estimating the energy content of hydrocarbon fuels such as gasoline, diesel fuel, and jet fuel.

Regenerative braking is one of the key enablers of improved energy efficiency and extension of driving range in parallel and series hybrid, and electric-only vehicles. It is still used in conjunction with friction brakes, due to the enormous amount of energy dissipated in maximum effort stops (and the lack of a competitive alternate technology to accommodate this power level), and to provide braking when on-board energy storage/dissipation devices cannot store enough energy to support braking. Although vehicles equipped with regenerative braking are becoming more and more commonly available, there is little published research on what the dramatic reduction in friction brake usage means to the function of the friction brakes themselves. This paper discusses -with supporting data from analysis and physical tests - some of the considerations for friction brakes related to usage on vehicles with regenerative braking, including corrosion, off-brake wear, and friction levels.

Over the last two decades, engine research was mainly focused on reducing fuel consumption in view of compliance with more stringent homologation cycles and customer expectations. As it is well known, the objective of overall engine efficiency optimization can be achieved only through the improvement of each element of the efficiency chain, of which mechanical constitutes one of the two key pillars (together with thermodynamics). In this framework, the friction reduction for each mechanical subsystem has been one of the most important topics of modern Diesel engine development. The present paper analyzes the crankshaft potential as contributor to the mechanical efficiency improvement, by investigating the synergistic impact of crankshaft design itself and oil viscosity characteristics (including new ultra-low-viscosity formulations already discussed by the author in [1]).

This study presents the comparison of vehicle handling performance results obtained using physical test tire data and a tire model developed by means of Finite Element Method. Real tires have been measured in laboratory to obtain the tire force and moment curves in terms of lateral force and align torque as function of tire slip angle and vertical force. The same tire construction has been modeled with Finite Element Method and explicit formulation to generate the force and moment response curves. Pacejka Magic Formula tire response models were then created to represent these curves from both physical and virtual tires. In the sequence, these tire response models were integrated into a virtual multibody vehicle model developed to assess handling maneuvers.

The paper describes the challenges and results achieved in developing a new high-speed Diesel combustion system capable of exceeding the imaginative threshold of 100 kW/l. High-performance, state-of-art prototype components from automotive diesel technology were provided in order to set-up a single-cylinder research engine demonstrator. Key design parameters were identified in terms boost, engine speed, fuel injection pressure and injector nozzle flow rates. In this regard, an advanced piezo injection system capable of 3000 bar of maximum injection pressure was selected, coupled to a robust base engine featuring ω-shaped combustion bowl and low swirl intake ports. The matching among the above-described elements has been thoroughly examined and experimentally parameterized.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

In order to increase the efficiency of automotive turbochargers at low speed without compromising the performance at maximum boost conditions, variable geometry compressor (VGC) systems, based on either variable inlet guide vanes or variable geometry diffusers, have been recently considered as a future design option for automotive turbochargers. This work presents a modeling, analysis and optimization study for a Diesel engine equipped with a variable geometry compressor that help understand the potentials of such technology and develop control algorithms for the VGC systems,. A cycle-averaged engine system model, validated on experimental data, is used to predict the most important variables characterizing the intake and exhaust systems (i.e., mass flow rates, pressures, temperatures) and engine performance (i.e., torque, BMEP, volumetric efficiency), in steady-state and transient conditions.

Powerful vehicles that are adequately designed to corner at high speeds can generate very high lateral forces at tire-road interface. These forces are counter balanced by chassis, suspension and brake components allowing the vehicle to confidently maneuver around a corner. Although these components may not damage under such high cornering loads, elastic deflections can significantly alter a vehicles performance. One such phenomenon is increased brake pedal travel, to engage brakes, after severe cornering maneuvers. Authors of this paper have worked together to solve exactly this problem on a very powerful luxury segment car.

We present a cost model that analyzes monetary costs for a product-line architecture to help the optimization of the architecture. The paper illustrates the usefulness of this methodology in a case study based upon the design exploration of a product-line architecture for an active safety system.

Automakers are designing smaller displacement engines with higher power densities to improve vehicle fuel economy, while continuing to meet customer expectations for power and drivability. The specific power produced by the spark-ignited engine is constrained by knock and fuel octane. Whereas the lowest octane rating is 87 AKI (antiknock index) for regular gasoline at most service stations throughout the U.S., 85 AKI fuel is widely available at higher altitudes especially in the mountain west states. The objective of this study was to explore the effect of gasoline octane rating on the net power produced by modern light duty vehicles at high altitude (1660 m elevation). A chassis dynamometer test procedure was developed to measure absorbed wheel power at transient and stabilized full power operation. Five vehicles were tested using 85 and 87 AKI fuels.

In practice, the piston wrist pin is either fixed to the connecting rod or floats between the connecting rod and the piston. The tribological behavior of fixed wrist pins have been studied by several researchers, however there have been few studies done on the floating wrist pin. A new bench rig has been designed and constructed to investigate the tribological behavior between floating pins and pin bore bearings. The experiments were run using both fixed pins and floating pins under the same working conditions. It was found that for fixed pins there was severe damage on the pin bore in a very short time (5 minutes) and material transfer occurs between the wrist pin and pin bore; however, for the floating pin, even after a long testing time (60 minutes) there was minimal surface damage on either the pin bore or wrist pin.

Regulations have been established for the monitoring and reporting of greenhouse gas (GHG) emissions and fuel consumption from the transport sector. Low carbon fuels combined with new powertrain technologies have the potential to provide significant reductions in GHG emissions while decreasing the dependence on fossil fuel. In this study, a lean-burn ethanol-diesel dual-fuel combustion strategy has been used as means to improve upon the efficiency and emissions of a conventional diesel engine. Experiments have been performed on a 2.0 dm3 single cylinder heavy-duty engine equipped with port fuel injection of ethanol and a high-pressure common rail diesel injection system. Exhaust emissions and fuel consumption have been measured at a constant engine speed of 1200 rpm and various steady-state loads between 0.3 and 2.4 MPa net indicated mean effective pressure (IMEP).

The friction material is arguably at the heart of any brake system, with its properties taking one of the most important roles in defining its performance characteristics. High performance applications, such as race track capable brake systems in high powered vehicles, exert considerable stress on the friction materials, in the form of very high heat flux loads, high clamp and brake torque loads, and high operating temperatures. It is important, for high performance applications, to select capable friction materials, and furthermore, it is important to understand fully what operating conditions the friction material will face in the considered application.

This paper investigates the application of the Hybrid FE-SEA method to the prediction of the Transmission Loss (TL) of a front-of-dash component. SEA subsystems are used to represent the source and receiving chambers of a TL test suite and an FE structural subsystem is used to represent the dash component. The potential advantages of the Hybrid FE-SEA method for this application are that: (i) it can provide detailed narrowband predictions of the radiation efficiency and TL of a given component across a broad frequency range and (ii) the computational cost of the approach is typically several orders of magnitude less than that of traditional low frequency FE/BEM/IEM methods. The approach is also potentially well suited to existing analysis processes since information from detailed component level models can be used to update and refine targets obtained from system level SEA models (the use of a common environment for such models simplifies model management).

DFSS (Design for Six Sigma) is a very useful method to optimize product design in various fields of the industry. This paper presents the implementation of the DFSS method to optimize an engine intake manifold with PDA system. The focus of optimization is to maximize the swirl strength and mass flow rate in the cylinder chamber. There are so many factors that affect the swirl strength and mass flow rate in intake manifold system, but only six main control factors such as plenum shape, primary and secondary length, port diameter, primary pipe section shape, etc. are adopted. The L18 orthogonal table is used for calculating CFD simulation to evaluate the swirl number and mass flow rate in the cylinder chamber.

Friction Launch transmissions use a wet multi-plate clutch to replace the torque converter in an automatic transmission. By using one of the range clutches inside the transmission, the benefits of this integrated friction launch technology (IFL), such as reduction in mass, packaging, and cost, can be enhanced. The availability of new automatic transmissions with higher number of speeds and wider ratio spreads makes IFL technology more viable than ever before. The new GM Rear-Wheel-Drive (RWD) six-speed transmission has paved the way for a full implementation of integrated friction launch technology in a GM full size Sport-Utility Vehicle (SUV). This project focuses on both hardware and control issues with the friction launch clutch. The hardware issues include designing the clutch for launch energy, cooling, and durability.

Time-averaged temperatures at critical locations on the piston of a direct-fuel injected, two-stroke, 388 cm3, research engine were measured using an infrared telemetry device. The piston temperatures were compared to data [7] of a carbureted version of the two-stroke engine, that was operated at comparable conditions. All temperatures were obtained at wide open throttle, and varying engine speeds (2000-4500 rpm, at 500 rpm intervals). The temperatures were measured in a configuration that allowed for axial heat flux to be determined through the piston. The heat flux was compared to carbureted data [8] obtained using measured piston temperatures as boundary conditions for a computer model, and solving for the heat flux. The direct-fuel-injected piston temperatures and heat fluxes were significantly higher than the carbureted piston. On the exhaust side of the piston, the direct-fuel injected piston temperatures ranged from 33-73 °C higher than the conventional carbureted piston.

The objective of this paper is to propose a new model in the identification of a contributing factor to the generation of Radio Frequency Interference (RFI) due to the operation of a spark-ignited engine. This model incorporates parameters in the electrical operation of the ignition system components and their interaction with the engine mechanical structure, which is also used as a circuit component (the ignition system “ground”). T he model was developed as a result of analysis of numerous studies that have been conducted over the years in an attempt to identify why RFI characteristics can differ when using identical components on different engines, or locating the components in different locations on identical engines. This situation is a problem due to the resulting uncertainty with respect to the determination of what is the optimum vehicle ignition system configuration to meet all electrical and RFI or electromagnetic compatibility (EMC) requirements.

The need for fuel economy gains is crucial in todays automotive market. There is also growing interest and knowledge of greenhouse gases and their effect on the environment. Paulstra's magnesium powertrain brackets were a solution that was presented not just to reduce the weight of the engine mounting system (which was already under its weight target before magnesium introduction), but in response of the OEM's desire to further reduce the weight of the vehicle for CAFE and weight class impact. This new engine mounting system has three powertrain mount brackets that are high-pressure die cast AZ91D magnesium alloy. This paper will show that these brackets to have a dramatic weight reduction compared to the standard aluminum die-cast material that they replaced. This paper describes the process of approval: concept and material sign-off by the OEM, FEA for strength and modal performance, corrosion, and the final product.