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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.

Octane appetite of modern engines has changed as engine designs have evolved to meet performance, emissions, fuel economy and other demands. The octane appetite of seven modern vehicles was studied in accordance with the octane index equation OI=RON-KS, where K is an operating condition specific constant and S is the fuel sensitivity (RONMON). Engines with a displacement of 2.0L and below and different combinations of boosting, fuel injection, and compression ratios were tested using a decorrelated RONMON matrix of eight fuels. Power and acceleration performance were used to determine the K values for corresponding operating points. Previous studies have shown that vehicles manufactured up to 20 years ago mostly exhibited negative K values and the fuels with higher RON and higher sensitivity tended to perform better.

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.

A vehicle thermal management system is required to increase the operating efficiency of components, to transfer the heat efficiently and to reduce the energy required for the vehicle. Vehicle thermal management technologies, such as engine compartment encapsulation together with grille shutter control, enable energy efficiency improvements through utilizing waste heat in the engine compartment for heating powertrain components as well as cabin heating and reducing the aerodynamic drag . In this work, a significant effort is put on recovering waste heat from the engine compartment to provide additional efficiency to the components using a motor compartment insulation technique and grille shutter. The tests are accelerated and the cost is reduced using a co-simulation tool based on high resolution, complex thermal and kinematics models. The results are validated with experimental values measured in a thermal wind tunnel, which provided satisfactory accuracy.

There is an increasing recognition of injector deposit (ID) formation in fuel injection equipment as direct injection spark ignition (DISI) engine technologies advance to meet increasingly stringent emission legislation and fuel economy requirements. While it is known that the phenomena of ID in DISI engines can be influenced by changes in fuel composition, including increasing usage of aliphatic alcohols and additive chemistries to enhance fuel performance, there is however still a great deal of uncertainty regarding the physical and chemical structure of these deposits, and the mechanisms of deposit formation. In this study, a mechanical cracking sample preparation technique was developed to assess the deposits across DISI injectors fuelled with gasoline and blends of 85% ethanol (E85).

Increasingly strict government emissions regulations in combination with consumer demand for high performance vehicles is driving gasoline engine development towards highly downsized, boosted direct injection technologies. In these engines, fuel consumption is improved by reducing pumping, friction and heat losses, yet performance is maintained by operating at higher brake mean effective pressure. However, the in-cylinder conditions of these engines continue to diverge from traditional naturally aspirated technologies, and especially from the Cooperative Fuels Research engine used to define the octane rating scales. Engine concepts are thus key platforms with which to screen the influence of fundamental fuel properties on future engine performance.

In Gasoline Direct Injection engines, direct exposure of the injector to the flame can cause combustion products to accumulate on the nozzle, which can result in increased particulate emissions. This research observes the impact of injector fouling on particulate emissions and the associated injector spray pattern and shows how both can be reversed by utilising fuel detergency. For this purpose multi-hole injectors were deliberately fouled in a four-cylinder test engine with two different base fuels. During a four hour injector fouling cycle particulate numbers (PN) increased by up to two orders of magnitude. The drift could be reversed by switching to a fuel blend that contained a detergent additive. In addition, it was possible to completely avoid any PN increase, when the detergent containing fuel was used from the beginning of the test. Microscopy showed that increased injector fouling coincided with increased particulate emissions.

Control of NOx and Particulate Matter (PM) emissions from diesel engines remains a significant challenge. One approach to reduce both emissions simultaneously without fuel economy penalty is the reformed exhaust gas recirculation (REGR) technique, where part of the fuel is catalytically reacted with hot engine exhaust gas to produce a hydrogen-rich combustible gas that is then fed to the engine. On the contrary to fuel cell technology where the reforming requirements are to produce a reformate with maximized H2 concentration and minimized (virtually zero) CO concentration, the key requirement of the application of the exhaust gas fuel reforming technique in engines is the efficient on-demand generation of a reformate with only a relatively low concentration of hydrogen (typically up to 20%).

Several different possibilities will be described and discussed on the processes of reducing NOx in lean-burn gasoline and diesel engines. In-company studies were conducted on zeolitic catalysts. With lean-burn spark-ignition engines, hydrocarbons in the exhaust gas act as a reducing agent. In stationary conditions at λ = 1.2, NOx conversion rates of approx. 45 % were achieved. With diesel engines, the only promising variant is SCR technology using urea as a reducing agent. The remaining problems are still the low space velocity and the narrow temperature window of the catalyst. The production of reaction products and secondary reactions of urea with other components in the diesel exhaust gas are still unclarified.

Over the next decades to come, fossil fuel powered Internal Combustion Engines (ICE) will still constitute the major powertrains for land transport. Therefore, their impact on the global and local pollution and on the use of natural resources should be minimized. To this end, an extensive fundamental and practical study was performed to evaluate the potential benefits of simultaneously co-optimizing the system fuel-and-engine using diesel as an example. It will be clearly shown that the still unused co-optimizing of the system fuel-and-engine (including advanced exhaust after-treatment) as a single entity is a must for enabling cleaner future road transport by cleaner fuels since there are large, still unexploited potentials for improvements in road fuels which will provide major reductions in pollutant emissions both in vehicles already in the field and even more so in future dedicated vehicles.

The blending of oxygenated compounds with gasoline is projected to increase because oxygenate fuels can be produced renewably, and because their high octane rating allows them to be used in substitution of the aromatic fraction in gasoline. Blending oxygenates with gasoline changes the fuels' properties and can have a profound affect on the distillation curve, both of which are known to affect engine-out emissions. In this work, the effect of blending methanol and ethanol with gasoline on unburned hydrocarbon and particulate emissions is experimentally determined in a spray guided direct injection engine. Particulate number concentration and size distribution were measured using a Cambustion DMS500. These data are presented for different air fuel ratios, loads, ignition timings and injection timings. In addition, the ASTM D86 distillation curve was modeled using the binary activity coefficients method for the fuel blends used in the experiments.

In addition to the price factor, the success of an electric vehicle primarily depends on its performance characteristics and operating range. Advances both in vehicle design and better technology help to improve these characteristics, thus providing the customer with a convincing vehicle concept. Three vehicle generations will be examined and the development advances between 1993 and 2003 will be listed by way of comparison. Improvement potential and technical limits will be analyzed from cost aspects. Since the limits of battery technology cannot be extended at will, it is necessary to develop both battery-driven electric vehicles and vehicles fitted with hybrid drive units. Based on the drive technology of purely electric-powered vehicles, concepts of range extender hybrid and fuel-cell hybrid vehicles will be presented.

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.

The regeneration of a Diesel Particulate Filter (DPF) is dependent on both the amount and type of soot present on the filter. The objective of this work is to understand how the fuel can affect this ease with which soot can be oxidized. This soot was produced in a two-cylinder four-stroke direct-injection diesel engine, operated with a matrix of fuels with varying aromatic and sulphur level. Their oxidation behaviour in different environments was determined by Temperature Programmed Oxidation in TGA and a six-flow reactor. Transmission electron microscopy was used to examine the soot morphology. Oxidation with only O2 shows oxidation temperatures strongly dependent on the fuel type. Soot oxidation in the presence of NO and a Pt-catalyst results in a lower oxidation temperature. SO2 has an inhibiting effect leading to higher soot oxidation temperature.

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.

An investigation was conducted to elucidate, how the latest turbocharged, direct injection Volkswagen diesel engine generation with cylinder pressure based closed loop control, to be launched in the US in 2008, reacts to fuel variability. A de-correlated fuels matrix was designed to bracket the range of US market fuel properties, which allowed a clear correlation of individual fuel properties with engine response. The test program consisting of steady state operating points showed that cylinder pressure based closed loop control successfully levels out the influence of fuel ignition quality, showing the effectiveness of this new technology for markets with a wide range of fuel qualities. However, it also showed that within the cetane range tested (39 to 55), despite the constant combustion mid-point, cetane number still has an influence on particulate and gaseous emissions. Volatility and energy density also influence the engine's behavior, but less strongly.

Limits on the total future potential of biodiesel fuel due to the availability of raw materials mean that ambitious 20% fuel replacement targets will need to be met by the use of both first and next generation biodiesel fuels. The use of higher percentage biodiesel blends requires engine recalibration, as it affects engine performance, combustion patterns and emissions. Previous work has shown that the combustion of 50:50 blends of biodiesel fuels (first generation RME and next generation synthetic fuel) can give diesel fuel-like performance (i.e. in-cylinder pressure, fuel injection and heat release patterns). This means engine recalibration can be avoided, plus a reduction in all the regulated emissions. Using a 30% biodiesel blend (with different first and next generation proportions) mixed with Diesel may be a more realistic future fuel.

Synthetic fuels are expected to play an important role for future mobility, because they can be introduced seamlessly alongside conventional fuels without the need for new infrastructure. Thus, understanding the interaction of GTL fuels with modern engines, and aftertreatment systems, is important. The current study investigates potential benefits of GTL fuel in respect of diesel particulate filters (DPF). Experiments were conducted on a Euro 4 TDI engine, comparing the DPF response to two different fuels, normal diesel and GTL fuel. The investigation focused on the accumulation and regeneration behavior of the DPF. Results indicated that GTL fuel reduced particulate formation to such an extent that the regeneration cycle was significantly elongated, by ∼70% compared with conventional diesel. Thus, the engine could operate for this increased time before the DPF reached maximum load and regeneration was needed.

The effects of various aspects of FAME quality and sources on injector nozzle fouling, when blended into diesel were investigated systematically. The B10 fuels used for this investigation are representative of available FAME qualities in the market. The variables used to assess quality were age, water content, saturation level, monoglycerides level, antioxidant content and feedstock. The B10 fuels were tested in a PSA (Peugeot Société Anonyme) DW10 bench engine operating to a modified version of the CEC (Coordinating European Council) F-98 Nozzle Coking Test. Power loss was used as the primary indicator of nozzle fouling. Power loss did not exceed 1% with any of the B10 blends tested, which is within the repeatability limits. These results show that this set of B10s, formulated with market quality and worst-case quality FAME, did not cause measurable injector nozzle fouling in this modified version of the industry standard engine test.

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.