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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.

Current developments in automotive industry such as hybrid powertrains and the continuously increasing demands on emission control systems, are pushing complexity still further. Validation of such systems lead to a huge amount of test cases and hence extreme testing efforts on the road. At the same time the pressure to reduce costs and minimize development time is creating challenging boundaries on development teams. Therefore, it is of utmost importance to utilize testing and validation prototypes in the most efficient way. It is necessary to apply high levels of instrumentation and collect as much data as possible. And a streamlined data pipeline allows the fleet managers to get new insights from the raw data and control the validation vehicles as well as the development team in the most efficient way. In this paper we will demonstrate a data-driven approach for validation testing.

In relation to further tightening of the emissions legislation for on-road heavy duty Diesel engines, the future potential of cooled exhaust gas recirculation (EGR) as a result of developments in the cooling systems of such engines has been evaluated. Four basic engine concepts were investigated: an engine with SCR exhaust gas aftertreatment for control of the nitrogen oxides (NOx), an engine with cooled EGR and particulate (PM) filtration, an engine with low pressure EGR and PM filtration and an engine with two stage low temperature cooled EGR also with a particulate filter. A 10.5 litre engine was calibrated and tested under conditions representative for each concept, such that 1.7 g/kWh (1.3 g/bhp-hr) NOx could be achieved over the ESC and ETC. This corresponds to emissions 15% below the Euro 5 legislation level.

The world of automotive engineering shows a clear direction for upcoming development trends. Stringent fleet average fuel consumption targets and CO2 penalties as well as rising fuel prices and the consumer demand to lower operating costs increases the engineering efforts to optimize fuel economy. Passenger car engines have the benefit of higher degree of technology which can be utilized to reach the challenging targets. Variable valve timing, downsizing and turbo charging, direct gasoline injection, highly sophisticated operating strategies and even more electrification are already common technologies in the automotive industry but can not be directly carried over into a motorcycle application. The major differences like very small packaging space, higher rated speeds, higher power density in combination with lower production numbers and product costs do not allow implementation such high of degree of advanced technology into small-engine applications.

Vehicle driveability evolves more and more as a key decisive factor for marketability and competitiveness of passenger cars, since the final decision of customers to buy a car is usually taken after a more or less intensive test drive. Car manufacturers currently evaluate vehicle driveability with subjective assessments and by having their experienced test drivers fill out form sheets. These assessments are time and cost intensive, limited in repeatability and not objective. The real customer requirements cannot be recognized in detail with this method. This paper describes a completely new approach for an objective and real time evaluation of relevant driveability criteria, for use in a vehicle and on a high dynamic test bed. The vehicle application enables an objective comparison between vehicles and an application as a development tool in many development and calibration phases, where ever fast and objective driveability results are required.

Gasoline direct injection is one of the main issues of actual worldwide SI engine development activities. It requires a comprehensive system approach from the basic considerations on optimum combustion system configuration up to vehicle performance and driveability. The general characteristics of currently favored combustion system configurations are discussed in this paper regarding both engine operation and design aspects. The engine performance, especially power output and emission potential of AVL's DGI engine concept is presented including the interaction of advanced tools like optical diagnostics and 3D-CFD simulation in the combustion system development process. The application of methods like tomographic combustion analysis for investigations in the multicylinder engine within further stages of development is demonstrated. The system layout and operational strategies for fuel economy in conjunction with exhaust gas aftertreatment requirements are discussed.

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.

Highest grow or highest attention in vehicles power-train is related to AWD and hybrid concepts. Some of the targets for these technologies are conflicting, others are very similar, and sometimes it depends on the application. In a first look it is very questionable weather these technologies should be combined. But it can be shown, that the combination makes quite some sense. It is possible to get the superior performance and enhance safety combined with reasonable fuel economy by hybridizing an AWD powertrain. From simulation to testing, efficient processes and a consistent development platform is key to fulfill all the development tasks in the environment of this increased complexity. Simulation and benchmark activities are valuable in the early project phases to define the targets and create the specifications. In the virtual world the system selection is a major task. To get appropriate results software modules are incorporated in the simulation environment.

The demand for improved fuel economy and the request for Zero Emission within cities require complex powertrains with an increasing level of electrification already in a short-termed timeframe until 2025. According to general expectations the demand for Mild-Hybrid powertrains will increase significantly within a broad range of implementation through all vehicle classes as well as on electric vehicles with integrated Range Extender (RE) mainly for use in urban areas. Whereas Mild Hybrid Vehicles basically use downsized combustion engines at current technology level, vehicles with a high level of powertrain electrification allow significantly different internal combustion engine (ICE) concepts. At AVL, various engine concepts have been investigated and evaluated with respect to the key criteria for a Range Extender application. A Wankel rotary engine concept as well as an inline 2 cylinder gasoline engine turned out to be most promising.

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.

Today combustion analysis has to be used in every step of the engine development process and is no longer a tool for some specialists but most test bed operators have to deal with combustion analysis (also called Indicating). AVL reacts on the widened area of application and the broad spread of the Indicating measurement technology by introduction of user friendly user interfaces, which make the work during preparation of measurements as well as during measurements itself easier.

The internal combustion engines, and the heavy duty truck diesel engines in particular, are facing a severe challenge to cope with the upcoming stringent emission legislation world-wide. To comply with these low limits, engine internal measures must be complemented with exhaust gas aftertreatment systems with sophisticated electronic control. A reduction of NOx and particulate emission of more than 90% is required. Various strategies to comply with Euro 4, 5 and US 2007 are discussed, also in view of engine performance, fuel economy and cooling system load. Recommendations are given for the most suitable approach to comply also in future with emission legislation in Europe and the United States.

A broad variety of new technologies for improving fuel economy is currently under development or investigation. The general statement is that always a compromise between fuel economy benefit and engine oncost has to be found. This paper describes a new way for improving fuel economy based on existing technologies used in a refined way. It is shown that with very simple and robust measures on the intake and exhaust ports and on the valve train mechanism 2 valve and 4 valve engines can show a significant improvement in fuel consumption without having a great cost penalty for production. The basic system consists of a single cam phaser and a special port arrangement on a 2 valve engine with a single camshaft operated at stoichiometric air/fuel ratio utilizing internal EGR and a reverse “Miller-Cycle”. Variable charge motion is generated using a shared flow through the intake and the exhaust port by varying cam timing.

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.

Local air pollution, noise emissions as well as global CO2 reduction and public pressure drive the need for zero emission transport solutions in urban areas. OEMs are currently developing battery electric vehicles with the focus to provide emission free urban transportation combined with lowest total cost of ownership and consequently a positive business case for the end customers. Thereby the main challenges are electric range, product cost, system weight, vehicle packaging and durability. Hence they are the main drivers in current developments. In this paper AVL describes two of its truck and bus solutions - a modular battery concept as well as a concept for an integrated electric axle. Based on the vehicle requirements concept designs for both systems are presented.

A TGDI (turbocharged gasoline direct injection) engine is developed to realize both excellent fuel economy and high dynamic performance to guarantee fun-to-drive. In order to achieve this target, it is of great importance to develop a superior combustion system for the target engine. In this study, CFD simulation analysis, steady flow test and transparent engine test investigation are extensively conducted to ensure efficient and effective design. One dimensional thermodynamic simulation is firstly conducted to optimize controlling parameters for each representative engine operating condition, and the results serve as the input and boundary condition for the subsequent Three-dimensional CFD simulation. 3D CFD simulation is carried out to guide intake port design, which is then measured and verified on steady flow test bench.

The reduction of CO₂ emissions represents a major goal of governments worldwide. In developed countries, approximately 20% of the CO₂ emissions originate from transport, one third of this from commercial vehicles. CO₂ emission legislation is in place for passenger cars in a number of major markets. For commercial vehicles such legislation was also already partly published or is under discussion. Furthermore the commercial vehicles market is very cost sensitive. Thus the major share of fuel cost in the total cost of ownership of commercial vehicles was already in the past a major driver for the development of efficient drivetrain solutions. These aspects make the use of new powertrain technologies, specifically hybridization, mandatory for future commercial powertrains. While some technologies offer a greater potential for CO₂ reduction than others, they might not represent the overall optimum with regard to the total cost of ownership.

Alternative fuels, especially fuels based on biological matter, are gaining more and more attention. Not only as a pure substitute of oil but also in terms of a possibility for further reduction in emission and as an option to improve the global CO2 balance. For improving the engine performance (emissions, fuel consumption, torque and drivability) the adjustment of fuel injection, the fuel evaporation process and the combustion process itself is paramount. In order to exploit the full potential of alternative fuels excellent knowledge of the fuel properties, including the impact on ignition and flame propagation, is required. This needs suitable tools for analysis of the fuel injection and combustion process. These tools have to support the optimization of the combustion system and the dynamic engine calibration for lowest emissions and most efficient use of fuel. As the term “Alternative Fuels” covers a very wide area a brief overview on available fuel types will be made.

Further fuel efficiency improvements are mandatory in order to achieve the CO2 emission limits envisaged in the future. Electrification of the powertrain is seen as one of the key technologies to achieve these future goals. However, electrification of the power train typically goes with a massive cost increase of the overall system itself which is especially crucial for cost sensitive markets like India. AVL's approach to cost reduction for comparable performance and fuel consumption target values is an integration of functions. This paper demonstrates that, through a deeper interaction of the single powertrain components, further fuel efficiency optimization may be gained. System optimization at a powertrain level enables the achievement of future powertrain targets with respect to fuel efficiency and performance with only minimal and reduced requirements at a component level (i.e. combustion engine, electric drive, transmission and battery).