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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.

This paper describes a method for optimization of engine settings in view of best total cost of operation fluids. Under specific legal NOX tailpipe emissions requirements the engine out NOX can be matched to the current achievable SCR NOX conversion efficiency. In view of a heavy duty long haul truck application various specific engine operation modes are defined. A heavy duty diesel engine was calibrated for all operation modes in an engine test cell. The characteristics of engine operation are demonstrated in different transient test cycles. Optimum engine operation mode (EOM) selection strategies between individual engine operation modes are discussed in view of legal test cycles and real world driving cycles which have been derived from on-road tests.

The paper outlines and discusses the possibilities of a new instrumentation tool for the analysis of engine and gearbox noise radiation and the prediction of pass-by noise from powertrain test cell measurements. Based on a 32 channel data acquisition board, the system is intended to be quick and easy to apply in order to support engineers during their daily work in the test cell. The pass-by prediction is a purely experimental approach with test cell recordings being weighted by measured transfer functions (from the powertrain compartment to the pass-by point).

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.

The paper gives an overview of the partially extremely complex problem when looking into commonalities and differences of the three main application areas of engines and powertrains - automotive, agricultural tractors, and industrial engines, the last being predominantly but not exclusively focused on construction equipment. The modern “platform” approach has been used in the automotive world to a large extent and the learned experiences may be of interest for the agricultural tractors and/or the construction equipment manufacturers. On the other hand the truck engine engineers and manufacturers will learn more about the special requirements of the tractor and the industrial engines fields, and thus influence concepts and development procedures and also the production of the automotive engines which in many cases serve as the basis for derivate engines.

Volvo Truck Corporation has developed a new cold-start method for heavy duty engines. The background for this new method is to get a high cold-start quality, at a low product cost for the customer. This paper describes the development of the new cold-start method, the layout for the system and the start procedure in low ambient temperature. The basic element for this start principle is to increase the temperature in the combustion chamber before the combustion begins. The tools for achieving higher temperature are the following: Precranking a number of revolutions without fuel injection. Produce a back-pressure in the exhaust pipe to reduce the gas exchange and decrease the loss of heat in the combustion chamber. Volvo Truck Corporation uses the new cold-start method in production of the D12 engine.

For commercial vehicles the availability of the truck has become increasingly important to the owner. Unexpected stops and visits to workshops are expensive nuisances not least if caused by some minor faults. The cab comfort and the vehicle response are fundamental to the driver. The accessibility and fault localizing are principal to the mechanic. The safety and the environmental impact are scrutinized by the authorities. The adaptability are vital to the dealers. The climate capability is needed to global presence and to long distance transports. Light weight structural solution permits heavy pay-loads. Low total usage cost is a must to be competitive. Advanced technology is implemented into the truck at increasing rate to satisfy all the aspects above. Quality has become the key issue to reach for the high standard demanded.

Experience front nearly six years in production of air-to-air (A-A) charge air cooling (CAC) is reported. Solutions to overcome the drawbacks of air-to-air compared to water-to-air charge air cooling are presented.

Particulate-bound hydrocarbons emitted by diesel engines have been analysed using a rapid new technique. The method involves directly loading filter-borne particulate into a modified injection port of a gas chromatograph. Hydrocarbons are vaporized in this solid sample injection system and subsequently become adsorbed on to a chromatography column. The merits of this procedure are demonstrated by comparing results with those obtained using conventional gas chromatography (with liquid injection) and thermogravimetry. The contribution of unburned engine oil to diesel particulate emissions has been investigated using the new method. For a DI truck diesel engine operated over the U.S. Federal Heavy Duty Transient Cycle it is shown that 40% of the particulate appears to be derived from unburned oil. For a comparable IDI truck diesel engine this value was 28%.

The paper presents the development and experiences of the multifuel TM101G engine. The standard TD101G engine, which is a turbocharged, direct injection engine with a displacement of 9.6 litres, was modified and equipped with two separate injection systems. Diesel fuel was used to ignite the alcohol. Performance and endurance tests were carried out, together with emission measurements. Twenty trucks and buses run on methanol or ethanol were involved in a field test. Fuel consumption and oil analyses were followed up.

In a consortium of European industrial partners and research institutes, a combination of industrial development and scientific research was organised. The objective was to improve the catalytic NOx conversion for lean burn cars and heavy-duty trucks, taking into account boundary conditions for the fuel consumption. The project lasted for three years. During this period parallel research was conducted in research areas ranging from basic research based on a theoretical approach to full scale emission system development. NOx storage catalysts became a central part of the project. Catalysts were evaluated with respect to resistance towards sulphur poisoning. It was concluded that very low sulphur fuel is a necessity for efficient use of NOx trap technology. Additionally, attempts were made to develop methods for reactivating poisoned catalysts. Methods for short distance mixing were developed for the addition of reducing agent.

On the path to decarbonizing road transport, electric commercial vehicles will play a significant role. The first applications were directed to the smaller trucks for distribution traffic with relatively moderate driving and range requirements, but meanwhile, the first generation of a complete portfolio of truck sizes is developed and available on the market. In these early applications, many compromises were accepted to overcome component availability, but meanwhile, the supply chain can address the specific needs of electric trucks. With that, the optimization towards higher usability and lower costs can be moved to the next level. Especially for long-haul trucks, efficiency is a driving factor for the total costs of ownership. Besides the propulsion system, all other systems must be optimized for higher efficiency. This includes thermal management since the thermal management components consume energy and have a direct impact on the driving range.