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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.

Two optical techniques were developed and combined with a CFD simulation to obtain spatio-temporally resolved information on air/fuel mixing in the cylinder of a methane-fueled, fired, optically accessible engine. Laser-induced fluorescence (LIF) of anisole (methoxybenzene), vaporized in trace amounts into the gaseous fuel upstream of the injector, was captured by a two-camera system, providing one instantaneous image of the air/fuel ratio per cycle. Broadband infrared (IR) absorption by the methane fuel itself was measured in a small probe volume via a spark-plug integrated sensor, yielding time-resolved quasi-point information at kHz-rates. The simulation was based on the Reynolds-averaged Navier-Stokes (RANS) approach with the two-equation k-epsilon turbulence model in a finite volume discretization scheme and included the port-fuel injection event. Commercial CFD software was used to perform engine simulations close to the experimental conditions.

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.

With the introduction of the New Beetle, Volkswagen is offering the next generation of the 1.9l TDI engine. Several evolutionary changes have been made to the TDI concept to further improve its emissions, efficiency and performance. Emissions performance is improved with increased fuel injection pressure, optimized fuel injectors, calibration modifications, EGR cooling and reduced crevice volume in the combustion chamber. Efficiency is improved with new oil pump, vacuum pump and water pump drive systems and the elimination of an auxiliary driveshaft. Performance and efficiency is improved with the addition of a variable geometry turbocharger, which increases torque at lower engine speeds while preserving performance at higher engine speeds. This paper describes the many enhancements found in this latest generation TDI and gives a brief lookout to the future trends in diesel engine development such as a high pressure injection system with unit injectors.

The use of a newly developed approach results in a highly accurate three dimensional analysis of the occupant movement. The central point of the new method is the calculation of precise body-trajectories by fitting standard sensor-measurements to video analysis data. With the new method the accuracy of the calculated trajectories is better than 5 to 10 millimeters. These body trajectories then form the basis for a new multi-body based numerical method, which allows the three dimensional reconstruction of the dummy kinematics. In addition, forces and moments acting on every single body are determined. In principle, the body movement is reconstructed by prescribing external forces and moments to every single body requiring that it follows the measured trajectory. The newly developed approach provides additional accurate information for the development engineers. For example the motion of dummy body parts not tracked by video analysis can be determined.

For substantial reduction of fuel consumption of their vehicle fleet, Volkswagen AG has decided to develop spark-ignition engines with direct fuel injection. To launch this new engine concept with stratified lean operation mode while at the same time meeting the stringent EU IV emission standards, it was necessary to develop a suitable exhaust gas aftertreatment system. This was achieved as part of an intensive co-operation between Volkswagen AG and OMG, formerly dmc2 Degussa Metals Catalysts Cerdec AG. The paper describes the demands for exhaust gas aftertreatment due to lean burn operation. In addition the main development steps of the exhaust gas aftertreatment system for Volkswagen FSI engines and catalyst durability over vehicle lifetime are discussed. Focus is laid on the catalyst system design and coating variations. Volkswagen developed a new closed-loop emission control management system which uses NOx-sensor signals for the first time worldwide.

Meeting the stringent efficiency demands of next generation direct injection engines requires not only optimization of the injection system and combustion chamber, but also an optimal in-cylinder swirling charge flow. This charge motion is largely determined by the shape of the intake port arm geometry and the valve position. In this paper, we outline an extensible methodology implemented in OPENFOAM® for multi-objective geometry optimization based on the continuous adjoint. The adjoint method has a large advantage over traditional optimization approaches in that its cost is not dependent upon the number of parameters being optimized. This characteristic can be used to treat every cell in the computational domain as a tunable parameter - effectively switching cells "on" or "off" depending on whether this action will help improve the objectives.

This paper summarizes the development of a wireless message from infrastructure-to-vehicle (I2V) for safety applications based on Dedicated Short-Range Communications (DSRC) under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). During the development of the Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure (RSZW/LC) safety applications [1], the Basic Information Message (BIM) was developed to wirelessly transmit infrastructure-centric information. The Traveler Information Message (TIM) structure, as described in the SAE J2735, provides a mechanism for the infrastructure to issue and display in-vehicle signage of various types of advisory and road sign information. This approach, though effective in communicating traffic advisories, is limited by the type of information that can be broadcast from infrastructures.

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.

Cervical Spine Distortions (CSD) - sometimes called whiplash injuries - have turned out in passenger car accidents to be one of the most important types of injuries to occupants, according to the rate of occurences and to the significance of consequences as well. Many technical aspects of traffic accidents which in the past have led to CSD have been analysed and reported in a large number of publications. However human factors data are not as good represented in the literature. Particularly these parameters and their relationship to whiplash injuries have been analysed on the basis of the Volkswagen Accident Database. The significance of the items gender, age, body height and body weight of belted occupants in passenger cars involved in rear end collisions is presented in quantitative terms regarding frequencies of occurance and risk of suffering CSD respectively.

A new method has been designed to examine car seats by technical means only, whether they fit summer conditions or not. Test procedures start with the application of a carefully wetted cloth onto the seat to be examined. The test area is then covered by a temperature controlled, electrically heated solid body bloc. This simulates the body temperature and the seat pressure of a real seat user. During test periods of standard three hours, temperature and humidity is measured beneath the test device and in the surrounding air. As an effect of the water impulse the humidity increases under the body bloc. It has been proved that good summer suitability of a car seat is characterised by moderate amount and moderate duration of increased humidity readings. Poor suitability results in higher amount and longer duration of raised humidity. The method is shown to be useful to examine full scale car seats, child safety seats and single design characteristics of car seats as well.

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.

This paper describes an investigation of one operating point of the transient warmup curve of a gasoline engine. Coolant liquid and oil of this engine have been cooled down to a constant low level in order to perform detailed measurements and an analysis of this particular warmup point. The influence of low coolant temperature, different pressure drop in an air assisted fuel injection system and a variation of ignition angles on specific fuel consumption, exhaust emissions, energy conversion etc. will be shown. The results show that the suggested test procedure (keeping the coolant temperature at a constant low level) provides the possibility to simulate the behaviour of an engine with air assisted fuel injection during warmup. During this warmup period it is desired to run the engine with retarded ignition timing to realize a fast catalyst warmup.

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.

Laser-induced exciplex fluorescence has been applied to the mixture formation process in the combustion chamber of an optically-accessible four-cylinder in-line spark-ignition engine in order to distinguish between liquid and vapor fuel distribution during the intake and compression stroke for different injection timings. The naphthalene/N,N,N′N′-tetramethyl p-phenylene diamine (TMPD) exciplex system excited at 308nm with a broadband XeCl excimer laser is used to obtain spectrally-separated, single-shot fluorescence images of the liquid or vapor phase of the fuel. For different timings of the fuel injector this technique is applied to obtain crank-angle-resolved images of the resulting mixture in the combustion chamber. The fluorescence light is detected with an intensified slow-scan CCD-camera equipped with appropriate filters.

Quantitative 1-D spatially-resolved NO LIF measurements in the combustion chamber of a mass-production SI engine with port-fuel injection using a tunable KrF excimer laser are presented. One of the main advantages of this approach is that KrF laser radiation at 248 nm is only slightly absorbed by the in-cylinder gases during engine combustion and therefore it allows measurements at all crank angles. Multispecies detection turned out to be crucial for this approach since it is possible to calculate the in-cylinder temperature from the detected Rayleigh scattering and the simultaneously acquired pressure traces. Additionally, it allows the monitoring of interfering emissions and spectroscopic effects like fluorescence trapping which turned out to take place. Excitation with 248 nm yields LIF emissions at shorter wavelengths than the laser wavelength (at 237 and 226 nm).

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.

Based an extensive preparatory work and analyses, suggestions have been drawn up with regard to solutions for front door frames in the following regions:- door hinge mountings, seat belt anchorage mountings of B pillars, cross sections for the top of A pillars. At the same time as the design work, FEM calculations should be carried out to ensure optimization of the concepts. Economy reasons and experiences in production runs point towards a very strong fibre glass-reinforced door frames manufacutred in the SMC procress. The complete door frame is examined in comparison with geometrically similar sheet metal parts on a test frame and in the vehicle.

The VOLKSWAGEN VANAGON SYNCRO is presented as a novel 4 WD. The visco coupling is the heart of the forward drive train. Main advantages are automatic performance distribution between the axles and self-locking at extreme revolution differences between front and rear. Another important advantage of the standard 2 WD Vanagon is the well-known excellent spring suspension and damping comfort which is not negatively effected by the 4 WD technique. The vehicle is equipped with a new more powerful engine with 2,1 liter displacement and 70 kW (95 HP) nominal power output which is based on the watercooled horizontally opposed engine program. Electronic fuel injection and ignition are integrated into a unique Volkswagen system called DIGIFANTR. Vehicle performance data and fuel economy figures are given in comparison with 2 WD designs and previously available engine power train combinations.