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To date, no generally valid statements can be made about the service life of brake pads, which may be due to factors such as driving style, the friction material used or the varying vehicle weight. While dynamic friction models including friction history are already established [1], the investigation of wear and wear dust behavior is currently in the focus of many research projects. One example is the investigation of calculation models for brake pad wear while neglecting the temperature development in the brake [2]. In cars, temperatures of up to 800°C occur in the brake under high loads, which leads to a significant increase in wear. Accordingly, the question arises how an estimation of brake pad wear can be applied to highly dynamic load cases. To do this, however, the processes taking place in the boundary layer between pad and disc must first be comprehensively understood and described.

Wireless Power Transfer (WPT) promises automated and highly efficient charging of electric and plug-in-hybrid vehicles. As commercial development proceeds forward, the technical challenges of efficiency, interoperability, interference and safety are a primary focus for this industry. The SAE Vehicle Wireless Power and Alignment Taskforce published the Recommended Practice J2954 to help harmonize the first phase of high-power WPT technology development. SAE J2954 uses a performance-based approach to standardizing WPT by specifying ground and vehicle assembly coils to be used in a test stand (per Z-class) to validate performance, interoperability and safety. The main goal of this SAE J2954 bench testing campaign was to prove interoperability between WPT systems utilizing different coil magnetic topologies. This type of testing had not been done before on such a scale with real automaker and supplier systems.

Over the past years, the question as to what may be the powertrain of the future has become ever more apparent. Aiming to improve upon a given technology, the internal combustion engine still offers a number of development paths in order to maintain its position in public and private mobility. In this study, an innovative combustion process is investigated with the goal to further approximate the ideal Otto cycle. Thus far, similar approaches such as Homogeneous Charge Compression Ignition (HCCI) shared the same objective yet were unable to be operated under high load conditions. Highly increased control efforts and excessive mechanical stress on the components are but a few examples of the drawbacks associated with HCCI. The approach employed in this work is the so-called Spark Assisted Compression Ignition (SACI) in combination with a pre-chamber spark plug, enabling short combustion durations even at high dilution levels.

This paper summarizes the validation of prototype vehicle-to-infrastructure (V2I) safety applications based on Dedicated Short Range Communications (DSRC) in the United States under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). After consideration of a number of V2I safety applications, Red Light Violation Warning (RLVW), Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure Warning (RSZW/LC) were developed, validated and demonstrated using seven different vehicles (six passenger vehicles and one Class 8 truck) leveraging DSRC-based messages from a Road Side Unit (RSU). The developed V2I safety applications were validated for more than 20 distinct scenarios and over 100 test runs using both light- and heavy-duty vehicles over a period of seven months. Subsequently, additional on-road testing of CSW on public roads and RSZW/LC in live work zones were conducted in Southeast Michigan.

Water vapor is, aside from carbon dioxide, the major fossil fuel combustion by-product. Depending on its concentration in the exhaust gas mixture as well as on the exhaust gas pressure, its condensation temperature can be derived. For typical gasoline engine stoichiometric operating conditions, the water vapor dew point lies at about 53 °C. The exhaust gas mixture does however contain some pollutants coming from the fuel, engine oil, and charge air, which can react with the water vapor and affect the condensation process. For instance, sulfur trioxide present in the exhaust, reacts with water vapor forming sulfuric acid. This acid builds a binary system with water vapor, which presents a dew point often above 100 °C. Exhaust composition after leaving the combustion chamber strongly depends on fuel type, engine concept and operation point. Furthermore, the exhaust undergoes several chemical after treatments.

Adoption of high-pressure common-rail (HPCR) fuel systems, which subject diesel fuels to higher temperatures and pressures, has brought into question the veracity of ASTM International specifications for biodiesel and biodiesel blend oxidation stability, as well as the lack of any stability parameter for diesel fuel. A controlled experiment was developed to investigate the impact of a light-duty diesel HPCR fuel system on the stability of 20% biodiesel (B20) blends under conditions of intermittent use and long-term storage in a relatively hot and dry climate. B20 samples with Rancimat induction periods (IPs) near the current 6.0-hour minimum specification (6.5 hr) and roughly double the ASTM specification (13.5 hr) were prepared from a conventional diesel and a highly unsaturated biodiesel. Four 2011 model year Volkswagen Passats equipped with HPCR fuel injection systems were utilized: one on B0, two on B20-6.5 hr, and one on B20-13.5 hr.

The regulations for mobile applications will become stricter in Euro 6 and further emission levels and require the use of active aftertreatment methods for NOX and particulate matter. SCR and LNT have been both used commercially for mobile NOX removal. An alternative system is based on the combination of these two technologies. Developments of catalysts and whole systems as well as final vehicle demonstrations are discussed in this study. The small and full-size catalyst development experiments resulted in PtRh/LNT with optimized noble metal loadings and Cu-SCR catalyst having a high durability and ammonia adsorption capacity. For this study, an aftertreatment system consisting of LNT plus exhaust bypass, passive SCR and engine independent reductant supply by on-board exhaust fuel reforming was developed and investigated. The concept definition considers NOX conversion, CO2 drawback and system complexity.

Internal combustion engines with lean homogeneous charge and auto-ignition combustion of gasoline fuels have the capability to significantly reduce fuel consumption and realize ultra-low engine-out NOx emissions. Group research of Volkswagen AG has therefore defined the Gasoline Compression Ignition combustion (GCI®) concept. A detailed investigation of this novel combustion process has been carried out on test bench engines and test vehicles by group research of Volkswagen AG and IAV GmbH Gifhorn. Experimental results confirm the theoretically expected potential for improved efficiency and emissions behavior. Volkswagen AG and IAV GmbH will utilize a highly flexible externally supercharged variable valve train (VVT) engine for future investigations to extend the understanding of gas exchange and EGR strategy as well as the boost demands of gasoline auto-ignition combustion processes.

Looking for car weight reduction related to the use of High Strength Steels (HSS) for manufacturing body-in-white components, an innovative application of the high velocity forming techniques has been developed: the Electro Magnetic (EM) calibration and elimination of the spring-back effect (sidewall curl) of High Strength Steel U-channels. Within this paper the initial tests on L and U-shaped parts will be presented. Being the mechanical stiffness the main parameter for improving the coil endurance, the prediction of the coil strains under EM forces is a basic issue, which has been addressed within this study.

This paper compares 4 different EGR systems by means of simulation in GT-Power. The demands of optimum massive EGR and fresh air rates were based on experimental results. The experimental data were used to calibrate the model and ROHR, in particular. The main aim was to investigate the influence of pumping work on engine and vehicle fuel consumption (thus CO2 production) in different EGR layouts using optimum VG turbine control. These EGR systems differ in the source of pressure drop between the exhaust and intake pipes. Firstly, the engine settings were optimized under steady operation - BSFC was minimized while taking into account both the required EGR rate and fresh air mass flow. Secondly, transient simulations (NEDC cycle) were carried out - a full engine model was used to obtain detailed information on important parameters. The study shows the necessity to use natural pressure differences or renewable pressure losses if reasonable fuel consumption is to be achieved.

Laser-based measurements of charge temperature and exhaust gas recirculation (EGR) ratio in an homogeneous charge compression ignition (HCCI) engine are demonstrated. For this purpose, the rotational coherent anti-Stokes Raman spectroscopy technique (CARS) was used. This technique allows temporally and locally resolved measurements in combustion environments through only two small line-of-sight optical accesses and the use of standard gasoline as a fuel. The investigated engine is a production-line four-cylinder direct-injection gasoline engine with the valve strategy modified to realize HCCI-operation. CARS-measurements were performed in motored and fired operation and the results are compared to polytropic calculations. Studies of engine speed, load, valve timing, and injection pressure were conducted showing the strong influence of charge temperature on the combustion timing.

Meeting current exhaust emission standards requires rapid catalyst light-off. Closed-coupled catalysts are commonly used to reduce light-off time by minimizing exhaust heat loss between the engine and catalyst. However, this exhaust gas system design leads to a coupling of catalyst heating and engine operation. An engine-independent exhaust gas aftertreatment can be realized by combining a burner heated catalyst system (BHC) with an underfloor catalyst located far away from the engine. This paper describes some basic characteristics of such a BHC system and the results of fitting this system into a Volkswagen Touareg where a single catalyst was located about 1.8 m downstream of the engine. Nevertheless, it was possible to reach about 50% of the current European emission standard EU 4 without additional fuel consumption caused by the BHC system.

In this paper we report on a new state of the art diesel LNT (Lean NOx Trap) formulation that is designed to comply with North American emission legislation for diesel passenger cars. Improved performance and durability is demonstrated in an aging study using hydrothermal furnace aging and a prolonged procedure behind the engine consisting of repeated cycles containing sulfur exposure, desulfation and simulated regeneration of a diesel particulate filter. The improved barium based technology shows an increased thermal stability in terms of upper not-to-exceed temperature of at least 50°C. Our data show that potassium based technologies can represent a viable solution for certain applications that require extremely high NOx-conversions at temperatures above 500°C. Potassium based technologies with improved anchoring of the alkali metal show significant reduction in potassium loss to the exhaust gas.

The growing demand for the use of magnesium alloys in the production of automotive powertrain components led to the development of creep resistant diecasting alloys MRI153M and MRI230D. The present paper addresses the main high-pressure die casting parameters, which significantly affect the performance of components, produced of these new alloys. A systematic study was carried out in order to correlate die-casting parameters to the performance of new alloys. The results obtained clearly indicated that optimization of molten metal and die temperatures, injection profile parameters and lubrication mixtures allowed to improve the die castability and service properties of the new alloys and produce high performance components with intricate geometry. This was manifested by production of several practical demonstrators such as gearboxes, oil pans, oil pumps and crankcases.

For the measurement of NO and NO2 the CLD-analyzer (chemiluminescense detector) has been used for more than twenty-five years. The disadvantage of the CLD is that NO can be measured only. To obtain total NOX (NO+NO2) the exhaust gas sample has to flow through a catalytic converter, which reduces NO2 to NO. The converter has a efficiency between 90 and 100%. For precise NO and NO2 values it is an advantage to analyze NO and NO2 directly. This paper describes a new UV NOX-analyzer for the simultaneous measurement of NO and NO2. Two different configurations, for high and low concentrations, eg. CVS-bag analysis are presented. The performance of the analyzers is documented in comparison to the UV-RAS analyzer with converter for NOX [1] and the conventional CLD-analyzer. The benefits of the new analyzer compared to analyzers equipped with a converter are given in detailed test results.

In direct-injection gasoline (GDI) engines with charge stratification, minimizing engine-out nitrogen oxide (NOx) emission is crucial since exhaust-gas aftertreatment tolerates only limited amounts of NOx. Reduced NOx production directly lowers the frequency of energy-inefficient catalyst regeneration cycles. In this paper we investigate NO formation in a realistic GDI engine. Quantitative in-cylinder measurements of NO concentrations are carried out via laser-induced fluorescence imaging with excitation of NO (A-X(0,2) band at 248 nm), and subsequent fluorescence detection at 220-240 nm. Engine modifications were kept to a minimum in order to provide results that are representative of practical operating conditions. Optical access via a sapphire ring enabled identical engine geometry as a production line engine. The engine is operated with commercial gasoline (“Super-Plus”, RON 98).

The need to reduce weight of large and heavy components used by the automotive and aerospace industries such as engine block, cylinder head cover and helicopter gearbox housing has led to the development of new Mg gravity casting alloys that provide adequate properties and cost effective solution. The new Mg gravity casting alloys are designed for high stressed components that operate at a temperature up to 300°C. These new alloys exhibit excellent mechanical properties and creep resistance in T-6 conditions. The present paper aims at introducing three new Mg gravity casting alloys designated MRI 201S, MRI 202S and MRI 203S, which were recently developed by the Magnesium Research Institute of DSM and VW. Apart from the excellent high temperature performance of these alloys, they provide adequate castability and dimension stability along with good weldability and corrosion resistance.

Compatibility has been a research issue for many years now. It has gained more importance recently due to significant improvements in primary and secondary safety. Using a rigorous approach, combining accident research and theoretical scientific considerations, measures to improve vehicle-vehicle compatibility, with an emphasis on feasibility, were discussed. German accident research statistics showed that frontal impacts are of higher statistical significance than side impacts. Based on this and the high potential for improvement due high available deformation energy, the frontal impact configuration was identified as the most appropriate collision mode for addressing the compatibility issue. In side impacts, accident avoidance was identified as the most feasible and sensible measure. For frontal vehicle-vehicle impacts, both trucks and passenger cars were identified as opponents of high statistical significance.

1 In this paper results obtained with different particulate matter (PM) reduction technologies are presented. Diesel oxidation catalysts (DOC) are well known as a reliable PM reduction technology which can efficiently remove the soluble organic fraction (SOF) but which has no effect on the solid particles in PM. A drawback is that in combination with high sulfur fuel, oxidation of SO2 to SO3 by the DOC can occur, resulting in an increase of PM emissions. An alternative technology that is proven to significantly reduce soot emissions comprises diesel particulate wall-flow filters. High filtration efficiencies of up to 90% and beyond are feasible. The main obstacle is the combustion of the trapped soot. As shown in this paper, the application of a catalyst coating to the filter aids the filter regeneration by lowering the balance-point temperature. The main disadvantages of wall-flow filters are an increase in back-pressure and possible plugging caused by oil-ash accumulations.

Recently several new magnesium alloys for high temperature applications have been developed with the aim to obtain an optimal combination of die castability, creep resistance, mechanical properties, corrosion performance and affordable cost. Unfortunately, it is very difficult to achieve an adequate combination of properties and in fact, most of the new alloys can only partially meet the required performance and cost. This paper aims at evaluating the current status of the newly developed alloys for powertrain applications. The paper also addresses the complexity of magnesium alloy development and illustrates the effect of alloying elements on properties and cost. In addition, the paper presents an attempt to set the position of each alloy in the integrated space of combined properties and cost