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Gasoline turbocharged direct injection (GTDI) engines, such as EcoBoost™ from Ford, are becoming established as a high value technology solution to improve passenger car and light truck fuel economy. Due to their high specific performance and excellent low-speed torque, improved fuel economy can be realized due to downsizing and downspeeding without sacrificing performance and driveability while meeting the most stringent future emissions standards with an inexpensive three-way catalyst. A logical and synergistic extension of the EcoBoost™ strategy is the use of E85 (approximately 85% ethanol and 15% gasoline) for knock mitigation. Direct injection of E85 is very effective in suppressing knock due to ethanol's high heat of vaporization - which increases the charge cooling benefit of direct injection - and inherently high octane rating. As a result, higher boost levels can be achieved while maintaining optimal combustion phasing giving high thermal efficiency.

Fuel Cells (FC) are promising candidates to reduce energy consumption and, hence, to improve the global climate situation due to significant gains in the process efficiencies. Whereas the development of fuel cells for passenger car applications has intensified during the last years, commercial vehicle applications have not been in the focus of developers so far. A reason for that is the limited availability of fuels such as hydrogen. Commercial vehicles are in the most cases operated with diesel fuel. AVL has developed three fuel cell applications for commercial vehicles operated with diesel fuel.

Dimethyl Ether has been proposed as alternative fuel for combustion engines. The paper gives a brief overview of resources, production, distribution and use of different automotive fuels and compares Dimethyl Ether with other oxygenated synthetic fuels recently proposed. For use in combustion engines Dimethyl Ether requires the introduction of new technologies, mainly in the field of fuel injection systems for direct injection. Such a fuel injection system is described in detail and measured characteristics are shown. For assessment of Dimethyl Ether from the environmental point of view, efficiencies and emissions during production and use of different fuels are summarized and discussed. For evaluation of environmental impacts a method is introduced which compares technical processes with natural cycles of substances and thus determines their “sustainability”.

In the past application of alternative fuels was mostly concentrated to special markets - e.g. for ethanol and ethanol blends Brazil or Sweden. Now an increasing sensitivity towards dependency on crude oil significantly enhances the interest in alternative fuels. With spark ignited engines, ethanol and gasoline / ethanol blends are the most promising alternative fuels - besides CNG. The high octane number of ethanol and the resulting excellent knock performance gives significant benefits, especially with highly boosted engines. However, the evaporation characteristics of ethanol result in challenges regarding cold start and oil dilution with GDI application. This paper deals with investigations on a turbocharged DI engine operated on ethanol fuel in order to improve challenges of ethanol fuel, such as oil dilution and cold start. Cold start can be improved by injecting fuel late in the compression stroke (high pressure start) based on a refined engine design and operation strategies.

Worldwide OBD legislation has and will be tightened drastically. In the US, OBD II for PC and the introduction of HD OBD for HD vehicles in 2010 will be the next steps. Further challenges have come up with the introduction of active exhaust gas aftertreatment components to meet the lower future emission standards, especially with the implementation of combined DPF-De-NOx-systems for PC and HD engines. Following such an increase in complexity, more comprehensive algorithms and software have to be developed to cope with the legislative requirements for exhaust gas aftertreatment devices. The calibration has to assure the proper functionality of OBD under all driving situations and ambient conditions. The increased complexity can only be mastered when new and efficient tools and methodologies are applied for both algorithm design and calibration. Consequently, OBD requirements have to be taken into account right from the start of engine development.

The reduction of nitrous oxides in the exhaust gases of internal combustion engines using a urea water solution is gaining more and more importance. While maintaining the future exhaust gas emission regulations, like the Euro 6 for passenger cars and the Euro 5 for commercial vehicles, urea dosing allows the engine management to be modified to improve fuel economy as well. The system manufacturer Robert Bosch has started early to develop the necessary dosing systems for the urea water solution. More than 300.000 Units have been delivered in 2007 for heavy duty applications. Typical dosing quantities for those systems are in the range of 0.01 l/h for passenger car systems and up to 10 l/h for commercial vehicles. During the first years of development and application of urea dosing systems, instantaneous flow measuring devices were used, which were not operating fully satisfactory.

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.

As emission regulations become tighter and tighter, equipment must evolve to be able to achieve the new standards. Also additional test requirements demand a system that is flexible and can accommodate differences both in the tests and the test facility. By that test cell equipment for chassis dynamometer as well as engine dynamometer applications is getting increasingly complex. That also will require new concepts for the design of such systems. In the past emission system design was more likely a collection and packaging process, which has interfaced various independent components. Now, the development of modern analytical emission systems requires a true holistic design process. This paper will describe the demands and the realization of a modern emission system. It can be shown that an extended effort during the design process will result in a high performance system, which still remains simple and robust.

Emission standards as proposed in Europe and the United States for heavy duty diesel engines will require a NOx and particulate reduction of more than 90%. This cannot be achieved by internal engine measures alone. Aftertreatment systems, for either one or both emission components, plus sophisticated electronic control strategies will be required. Various strategies to comply with EU 4, 5 and US 2007 are discussed, also showing their impact on engine performance. For typical 1 and 2 liter per cylinder engines, emission reduction concepts are assessed to identify the most suitable technology for major worldwide markets. The assessment is based on thermodynamic studies, test-bed results and estimates on cost and infrastructure implications.

DiMethyl Ether (DME) has been shown to be a very attractive fuel for low emission direct injection compression ignition (DICI) engines. It combines the advantages of the high efficiencies of diesel cycle engines with soot free combustion. However, its greatest drawback is the need to develop new fuel injection and handling systems. Previous approaches have been common rail type injection systems which have shown great potential in reducing harmful exhaust emissions and achieving good engine performance and efficiency due to good control of both the fuel injection characteristics and temperature. The concept also has proven benefits with respect to convenient and safe fuel handling. The logical evolution of this concept simplifies the fuel system and avoids special components for DME handling such as high pressure rail pumps while retaining all the benefits of the common rail principle.

Over the last few years there has been much interest in DiMethyl Ether (DME) as an alternative fuel for diesel cycle engines. It combines the advantages of a high cetane number with soot free combustion, which makes it eminently suitable for compression ignition engines. However, due to the fact that it is a gas under ambient conditions, it requires special fuel handling and a specially designed fuel injection system, which until recently, was not available. The use of the digital hydraulic operating system (DHOS), combined with a fuel handling system designed to cope with the properties of DME, enables the fuel to be safely and conveniently handled, In addition, the flexibility of the injection system enables injection pressures to be chosen according to the needs of the combustion.

The well-to-wheel CO2 emissions and energy use of internal combustion engines (diesel and gasoline) are compared to fuel cell automotive propulsion systems. The fuel cell technologies investigated are polymer electrolyte fuel cell (PEFC), alkaline fuel cell (AFC) and solid oxide fuel cell (SOFC). The fuels are assumed to be produced from either crude oil or natural gas. The comparison is based on driving cycle simulations of a mid-class passenger car with an inertia test weight of 1350 kg. The study shows that the optimized diesel drive train (downsized mated to an integrated starter generator) achieves the best overall energy efficiency. The lowest CO2 emissions are produced by compressed natural gas (CNG) vehicles. Fuel cell propulsion systems achieve similar or even better CO2 emission values under hot start conditions but suffer from high energy input required during warm-up.

Exhaust emission legislation world-wide have a common trend towards very low limits, measured for compliance in transient cycles specific for the United States, Japan and Europe. The emission development strategy is focussing on lowest engine-out emissions to require a minimum of exhaust gas aftertreatment. The base engine concept is described and test results, complying with Euro 4, are shown. The emission reduction development for future regulations requires exhaust gas aftertreatment, test results are shown for US 2007, JNLTR and Euro 5. With exhaust gas aftertreatment, discussed in the appendix, the engine development is faced with a big challenge to ensure the minimum exhaust gas temperature required for their proper function.

In recent years several new gasoline engine technologies were introduced in order to reduce fuel consumption. Controlled autoignition seems to be an alternative to stratified part load operation, which is handicapped due to it's lean aftertreatment system for world wide application. The principal advantages of controlled auto ignition combustion under steady state operation - combining fuel economy benefits similar to stratified charge systems with nearly negligible NOx and soot emissions - are already well known. With the newly developed AVL- CSI system (Compression and Spark Ignition), a precise combustion control is achieved even under transient operation. For compensation of production and operation tolerances a cost optimized cylinder individual control was developed. Completely new functionalities of the engine management system are applied. This lean GDI concept complies with future emission standards without DeNOx catalyst and can be applied worldwide.

The combined requirement of achieving CAFE values between 32 to 38 mpg plus LEV/ULEV emission standards to comply with US legal requirements between 1995 and 2000 represents the most demanding challenge for engine engineering. Thus all possible methods of engine improvement towards fuel economy and emissions have to be considered. Besides using new ideas also the methods of engine development have to be modernized to cope with the challenge. The paper presents advanced combustion and exhaust gas aftertreatment systems which combine high power output, favourable torque characteristics and high fuel economy with the potential for obtaining LEV/ULEV emission values, as well as improved development techniques.

With the implementation of EURO VI and similar emission legislation, the industry assumed the pace and stringency of new legislation would be reduced in the future. The latest announcements of proposed and implemented legislation steps show that future legislation will be even more stringent. The currently leading announced legislation, which concerns a large number of global manufacturers, is the legislation from the United States (US) Environmental Protection Agency (EPA) and the California Air Resources Board (CARB). Both announced new legislation for CO2, Greenhouse Gas (GHG) Phase II. CARB is also planning additional Ultra Low NOx regulations. Both regulations are significant and will require a number of technologies to be used in order to achieve the challenging limits. AVL published some engine related measures to address these legislation steps.

No abstract available.

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.

One main general goal during product development in the passenger car industry as well as in the commercial vehicle industry is to reduce time to market. The customer wants to get the newest product and is not accepting the risk of any product call backs. This means the minimization of the risk of field claims for the manufacturer. The challenge to reach this goal is a capable volume production of each new product. To create a competitive, innovative product it is the task for design and simulation engineers in the development phase to design the product in view of function, efficiency, fatigue strength, optimized weight and optimized product costs. Additionally an agreement between design and industrial production planning is required. An early involvement of production engineers into the development of a product ensures design for manufacturing from the very beginning.