Heimo Schreier

Electrically assisted turbocharging in long-haul truck application

Electric charging systems were investigated with regard to its performance potential on a classical 12L class heavy duty diesel engine. To assess the overall system behavior and to find best system configuration, characteristic operation modes for electric boosting and electric energy recuperation were investigated by 1/D simulations. Besides this detailed analysis in selected load points, a more holistic analysis was executed by a combined engine, vehicle and drivetrain simulation considering mixed highway, country road and city drive situation of a 40 ton semi-trailer truck. As a boundary for the electric boosting and electric energy recuperation systems a 48 V vehicle on-board power network was considered.

Combustion concepts for commercial gas engines with highest efficiencies

In the last years truck manufacturers worldwide brought more and more natural gas engines on the market, mainly motivated by the cost benefit of natural gas and expected limitations of CO2 emissions in future. Recently the main benefit of natural gas, the lower fuel price compared to diesel, reduced substantially or even disappeared due to significant price decline of diesel and gasoline, at least on the US-American and European market, as Figure 1 shows.

Electrification in the powertrain mix 2025 – effects on application development for commercial vehicles

CHANGE – The automotive industry as well as the transport industry are facing a big change. The demand for e-driven vehicles is getting higher, not just because of debates about “driving restriction within cities”, “fine dust” or “CO2”. But, the worldwide increase of urbanisation is the key driver for the alternative driven automobiles. Additionally, trucks and busses are an essential part of the city’s daily life.

Neue Technologien für Verbrennung – Ladungswechsel – Mechanik – Einspritzung

The development of commercial vehicle on-road applications, such as long haul trucks or busses, is driven by the optimization of the total cost of ownership (TCO) which relates the initial product cost with operating cost. Long haul truck applications have high annual mileage at high engine loads. Thus the operating costs dominate the total cost of ownership. Consequently lowest possible fuel consumption is one of the major drivers for long haul truck applications all over the world.

Future Commercial Vehicle Powertrains: Contributions to Sustainable Transportation

Objective Already for many years, fuel consumption and operating cost were the major technology drivers for commercial vehicles. Today, in order to achieve agreed CO2 goals and to reduce the dependency on crude oil, governments are implementing CO2 or fuel consumption legislation. Even more, reduction of fuel consumption and consequently low operating costs are continuously an important focus for manufacturers and owners of commercial vehicles. New powertrain technologies, which will further reduce fuel consumption, are able to combine these three drivers, to reduce CO2 emission, to reduce the dependency on crude oil and to address the need of lower total cost of ownership of the owners of commercial vehicles. Conclusions The efficiency of commercial powertrains can be significantly increased in future. Several potentials for improvement are seen specifically in those technologies, which are able to provide a global optimum of the whole powertrain system, from engine to exhaust aftertreatment to cooling system up to transmission and the final drive. In total a fuel efficiency potential of 20 % is seen for long haul trucks. Results AVL has developed a whole line of technologies, which can be implemented to the commercial powertrain in the future to address the requirements above. The individual measures are the optimization of the balance between engine and aftertreatment systems, reduced engine friction by advanced thermal management systems, reduced parasitic losses of the auxiliaries in real life driving cycles, conversion of exhaust energy in driving power, application of new and advanced transmission technologies and shift strategies as well as degrees of electrification of the powertrain. Additionally, alternative fuels provide another field of CO2 friendly technologies as well as reduced operating cost. Here specifically, the availability of local resources drive short term applications. This paper will compare the individual saving potentials of these technologies, will rate it against criteria like market readiness, cost efficiency and others. It will be demonstrated that major reductions in CO2 emissions and operating cost are still possible by commercial vehicle powertrain measures. Methodology To quantify the fuel saving potentials of the individual technologies AVL applied its proven seamless system simulation environment to analyze the whole vehicle system. Interlinked sub-models for all relevant vehicle, respectively engine sub-systems, are the core of this simulation environment. Where necessary, the individual models have been aligned with specific test bed and vehicle measurements. For some of the analyzed technologies the predicted fuel saving potential could already be confirmed by transient operation on test bed using prototype components. To analyze the cost efficiency for the individual technologies the predicted additional product costs have been rated against the saving in operational cost for the final vehicle owner. A return of investment calculation analysis has been made for each individual technology. To predict the market readiness of the individual technology, relevant boundary conditions like estimated development effort, components availability, established supplier base, development risk, etc. have been considered. Limitations Basically the results of this study can be transferred to all commercial powertrain systems. However, the main focus of the study is on the long haul truck application since it has the most significant impact to total CO2 emissions caused by the high mileage as well as the high absolute fuel consumption level of this vehicle category.