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Recently, a particle number (PN) limit was introduced in the European light-duty vehicles legislation. The legislation requires measurement of PN, and particulate mass (PM), from the full dilution tunnel with constant volume sampling (CVS). Furthermore, PN measurements will be introduced in the next stage of the European Heavy-Duty regulation. Heavy-duty engine certification can be done either from the CVS or from a partial flow dilution system (PFDS). For research and development purposes, though, measurements are often conducted from the raw exhaust, thereby avoiding the high installation costs of CVS and PFDS. Although for legislative measurements requirements exist regarding sampling and transport of the aerosol sample, such requirements do not necessarily apply for raw exhaust measurements. Thus, measurement differences are often observed depending on where in the experimental set up sampling occurs.

Volkswagen is the first automobile manufacturer to supply a passenger car with a direct fuel injection diesel engine to the US market, starting 1996. To meet the stringent US exhaust gas legislation the very successful European 1.9 liter TDI engine has been further developed for the 1996 and 1997 Passat. This TD1 incorporates a number of innovations in advanced diesel technology. Emissions-reducing innovations include: reduced crevice volume higher injection pressures upgraded injection management integrated EGR manifold system EGR cooling diesel catalytic converter This TDI engine configuration is also to be offered in the 1997 Golf and Jetta class and the new Passat in model year 1998. Over the coming years the TDI engine concept will be further optimized by utilizing variations of the above innovations.

Under city driving conditions, the powertrain represents one of the major vehicle exterior noise sources. Especially at idle and during full load acceleration, the oil pan contributes significantly to the overall powertrain sound emission. The engine oilpan can be a significant contributor to the powertrain radiated sound levels. Passive optimization measures, such as structural optimization and acoustic shielding, can be limited by e.g. light-weight design, package and thermal constraints. Therefore, the potential of the Active Structure Acoustic Control (ASAC) method for noise reduction was investigated within the EU-sponsored project InMAR. The method has proven to have significant noise reduction potential with respect to oil pan vibration induced noise. The paper reports on activities within the InMAR project with regard to a passenger car oil pan application of an ASAC system based on piezo-ceramic foil technology.

The acoustics insulation on the car body is ones of the more important target in the NVH (Noise Vibration and Harshness) vehicle development process. The method of SEA is a validated statistical approach to solve airborne noise transmission problems. In the vehicle analysis above 300 Hz where material trim and leakage paths makes a important contribution in the vehicle interior acoustics shows the methodology its advantages over deterministic methods.

The DEXA Cluster consisted of three closely interlinked projects. In 2003 the DEXA Cluster concluded by demonstrating the successful development of critical technologies for Diesel exhaust particulate after-treatment, without adverse effects on NOx emissions and maintaining the fuel economy advantages of the Diesel engine well beyond the EURO IV (2000) emission standards horizon. In the present paper the most important results of the DEXA Cluster projects in the demonstration of advanced particulate control technologies, the development of a simulation toolkit for the design of diesel exhaust after-treatment systems and the development of novel particulate characterization methodologies, are presented. The motivation for the DEXA Cluster research was to increase the market competitiveness of diesel engine powertrains for passenger cars worldwide, and to accelerate the adoption of particulate control technology.

The limitation of global warming to less than 2 °C till the end of the century is regarded as the main challenge of our time. In order to meet COP21 objectives, a clear transition from carbon-based energy sources towards renewable and carbon-free energy carriers is mandatory. Polymer electrolyte membrane fuel cells (PEMFC) allow an energy-efficient, resource-efficient and emission-free conversion of regenerative produced hydrogen. For these reasons fuel cell technologies emerge in stationary, mobile and logistic applications with acceptable cruising ranges as well as short refueling times. In order to perform applied research in the area of PEMFC systems, a highly integrated fuel cell analysis infrastructure for systems up to 150 kW electric power was developed and established within a cooperative research project by HyCentA Research GmbH and AVL List GmbH in Graz, Austria. A novel open testing facility with hardware in the loop (HiL) capability is presented.

This paper presents the results of an investigation on the influence of a duct’s geometry and shape on its acoustic length, which differs from its physical length by a factor referred to as end-correction. In addition to traditional parameters such as length and diameter, the author has investigated the effect of additional geometry features which are less commonly addressed in the technical literature, such as a diameter contraction or a bent section along the duct. The relative microphone position with respect to the pipe orifice and to the ground surface of the measurement environment has been investigated, showing negligible impact on the measurement results. The sound wave propagation within a pipe featuring a diameter contraction has then been analysed, showing the relationship between the pipe contraction shape and location and the pipe acoustic length.

Within the European research programme IDEA (Integrated Diesel European Action), detailed experimental and theoretical studies of the fundamental phenomena of the Diesel engine like flow, injection, mixture formation, auto-ignition, combustion and pollutant formation were carried out to improve knowledge and to set up models for a simulation code. Because this basic research of the Diesel combustion process is very complex and cost intensive, it was carried out jointly by the JRC (Joint Research Committee), an association of European car manufacturers (Fiat, Peugeot SA, Renault, Volvo and Volkswagen). The activities were also subsidized by the Commission of the European Communities and the Swedish National Board of Technical Development. The results of the research work will support the design of even more efficient engines and the further reduction of soot and NOx emissions and will also enable the companies to reduce time and cost in developing new engines.

In a joint research project between industrial companies and a number of research institutes, nitrogen oxide conversion in oxygen containing exhaust gas has been investigated according to the following procedure Basic investigations of elementary steps of the chemical reaction Production and prescreening of different catalytic material on laboratory scale Application oriented screening of industrial catalyst material Catalyst testing on a lean bum gasoline engine, passenger car diesel engines (swirl chamber and DI) and on a DI truck engine Although a number of solid body structures show nitrogen oxide reduction by hydrocarbons, only noble metal containing catalysts and transition metal exchanged zeolites gave catalytic efficiencies of industrial relevance. A maximum of 25 % NOx reduction was found in the European driving cycle for passenger cars, about 40 % for truck engines in the respective European test.

Both linear (frequency domain) and non-linear (time domain) prediction codes are used for the simulation of duct acoustics in exhaust systems. Each approach has its own set of advantages and disadvantages. One disadvantage of the linear method is that information about the engine as an acoustic source is needed in order to calculate the insertion loss of mufflers or the level of radiated sound. The source model used in the low frequency plane wave range is the linear time invariant 1-port model. This source characterization data is usually obtained from experimental tests where multi-load methods and especially the two-load method are most commonly used. These measurements are time consuming and expensive. However, this data can also be extracted from an existing 1-D non-linear CFD code describing the engine gas exchange process.

Compatibility has been a passive safety research issue for many years. Great advancements in secondary (passive) safety have been achieved in the last decades through focussing on the self-protection level provided by passenger cars. The next step is to consider the other vehicle involved in the collision as well. Compatibility relates to the simultaneous improvement of both self- and partner- protection. Several tests procedures have been proposed around the world to assess the compatibility of passenger cars. None are considered ready to be implemented. This paper shows that controlling vehicle front-end geometry is the most feasible step to improve both self- and partner-protection. Through this, an increase in the structural interaction potential offered by passenger cars would result. To improve structural interaction, a convergence of front-end structures, to within certain vertical limits, is necessary.

This paper focuses on psychoacoustical experiments for the assessment of roughness by using vehicle interior noise. The experimental design is carried out carefully to derive reliable data for further analysis with objective parameters. Apart from the acoustical properties of the recording/playback system the different meanings of the word roughness are taken into account, because each person has its own interpretation of ‘roughness’ differing between the phenomenons of roughness, r-roughness, rumble, harshness, fluctuation strength, etc.. An important preparation for psychoacoustical experiments is a clear definition of the sound attribute under investigation by using typical examples. Furthermore, accidental influences of other psychoacoustical parameters like the influence of loudness have to be avoided.

Originally developed for the automotive market, a fully automatic real-time measurement tool AVL-DRIVE is commercially available for analyzing and scoring vehicle drive quality, also known as “Driveability”. This system from AVL uses its own transducers, calibrated to the sensitivity and response of the human body to measure the forces felt by the driver, such as acceleration, shock, surging, vibration, noise, etc. Simultaneously, the vehicle operating conditions are measured, (throttle grip angle, engine speed, gear, vehicle speed, temperature, etc.). Because the software is pre-programmed with the scores from a multitude of different vehicles in each vehicle class via neural networks and fuzzy logic formula, a quality score with reference to similar competitor vehicles is instantly given. This tool is already successfully implemented in the market for years to investigate such driveability parameters for passenger cars.

The reduction of both harmful emissions (CO, HC, NOx, etc.) and gases responsible for greenhouse effects (especially CO2) are mandatory aspects to be considered in the development process of any kind of propulsion concept. Focusing on ICEs, the main development topics are today not only the reduction of harmful emissions, increase of thermodynamic efficiency, etc. but also the decarbonization of fuels which offers the highest potential for the reduction of CO2 emissions. Accordingly, the development of future ICEs will be closely linked to the development of CO2 neutral fuels (e.g. biofuels and e-fuels) as they will be part of a common development process. This implies an increase in development complexity, which needs the support of engine simulations. In this work, the virtual modeling of real fuel behavior is addressed to improve current simulation capabilities in studying how a specific composition can affect the engine performance.

Importance of electric and hybrid vehicles steeply increased in the last few years. Especially topics like CO2 reduction and local zero emissions are forcing companies to focus on electrification. While main technical problems seem to be solvable from a technical point of view, commercial and security topics are gaining more importance. For full electric vehicles the driving range is limited by the capacity of available batteries. As those batteries are one of the most heavy and expensive parts of these vehicles, reduction of battery size is a big topic in vehicle development. To increase a vehicle's driving range without increasing battery size some range extending backup system has to be available. Such a Range Extender should be a small system combining combustion engine and electric generator to produce the required electricity for charging the batteries whenever required.

The vehicle fleet differs in mass, geometry, stiffness and many other parameters. These differences are consequences of different design objectives for these vehicles and result from consumer demand, environmental and safety considerations etc. Accident research shows that the injury outcome differs in some cases, when two vehicles collide. Scientists often discuss a list of features that are assumed to be relevant for compatibility of vehicles. The relevance of these potentially important compatibility features and expected compatibility measures is examined from the perspective of accident analysis. An overview of this accident research is given and crash tests and measures are discussed that correspond with these findings.

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.

The turbulent flow around vehicles causes high amplitude pressure fluctuations at the underbody, consisting of both hydromechanic and acoustic contributions. This induces vibrations in the underbody structures, which in turn may lead to sound transmission into the passenger compartment, especially at low frequencies. To study these phenomena we present a run time fully coupled acoustic-fluid-structure interaction framework expanding a validated hybrid CFD-CAA solver. The excited and vibrating underbody is resembled by an aluminium plate in the underbody of the SAE body which allows for sound transmission into the interior. Different excitation situations are generated by placing obstacles at the underbody upstream of the aluminium plate. For this setup we carry out a fully coupled simulation of flow, acoustics and vibration of the plate.

Even though a number of developed countries enjoy a high level of vehicle safety, more than 1.2 million fatalities still occur each year on roadways worldwide. There remains a need to continue improving vehicle and road safety. New technologies in sensors and electronic control units, and the growing knowledge of car-to-car and car-to-infrastructure technologies have led to a fusion of the previously separated areas of accident avoidance (popularly known as active safety) and mitigation of injuries (popularly known as passive safety) into the newer concept of integrated vehicle safety. This new approach represents a further step toward lowering accident rates. This book, written by two of the foremost automotive engineering safety experts, takes a unique and comprehensive approach to describing all areas of vehicle safety: accident avoidance, pre-crash, mitigation of injuries, and post-crash technologies, providing a solutions-based perspective of integrated vehicle safety.