Internationaler Motorenkongress 2017

Overall industry and thus also automobile industry is currently changing dramatically driven by digitalization. Future mobility will be more than moving from A to B. The car of the future will be the connection between digital world and passenger. In the far future it is likely that it will be electric, connected and autonomous.Four key megatrends – demographic change, urbanization, environmental policy and connectivity – are analyzed in relation to their impact on people, future mobility and therefore on the automobile industry.Market forecasts predict an increase in the share of electrified vehicles from today 3 % to 27 % in 2023. However the share of pure electric vehicles will remain on a comparatively low level below 5 %. In order to meet upcoming CO₂ legislation a strategy of improving the conventional gasoline and Diesel engine as well as introducing a wide range of eco-friendly vehicles is required. With the fuel cell ix35 Hyundai is offering today the technology of tomorrow.Automated driving – thus car is capable of sensing its environment and handling of navigating tasks under all roadway conditions without human input – will become reality step by step.This presentation describes the Hyundai Motors development roadmap to satisfy the requirements towards future mobility in terms of innovative powertrain technologies, connectivity and autonomous driving.

Quote from: ‘Natural Gas and Renewable Methane for Powertrains’ Future Strategies for a Climate-Neutral Mobility “An element in the action plan to achieve the global 2-degree goal is that transportation at least massively limits the growth in its greenhouse gas emissions or rather contributes significantly to a reduction in emissions. This is necessary on both a national and a global level. The whole world is experiencing a massive surge in the growth of the volume of traffic: all forecasts point to further growth. It is therefore a problem of global proportions for which an exclusively national view is insufficient. Apart from the different boundary conditions in the various regions, it must be noted that the different transportation platforms have different growth and have different potential and options for the reduction of greenhouse gases. Forecasts assume that the GHG emissions due to transportation will more than double by 2050, from 6 GtCO_2,eq to 14 GtCO_2,eq.Since economic growth and traffic growth are coupled in many countries, steps to drastically reduce the volume of traffic or to reduce its growth are politically difficult to impose. The conclusion is that it is highly probable that only minor successes can be achieved in this area. It appears that the key to the traffic-based climate issue lies in the domain of traffic energy supply.There are a variety of options available for the different transportation platforms: The direct use of electricity based on renewable energy is practicable. The current level of knowledge states that there are no short or medium term globally available options for the direct use of electricity for heavy-duty traffic, shipping or aviation. However it must be mentioned that the direct use of electricity in commercial vehicles is in its infancy. Since the greenhouse gas emissions from the traffic sector from a global perspective are currently still increasing, the pressure to act and solve issues in traffic is growing rapidly. It is therefore high time to develop strategies to make technologies and energy carriers available for the transportation sector and if possible other sectors too that have no negative impact on the climate.An important element in such a strategy is, according the wisdom of today, the production of synthetic methane utilizing electricity. This affects the purely technological availability of production and its future development. It can be the basis for a climateneutral energy supply for transportation, where for example direct use of electricity (rail, passenger car, light‑duty trucks) is not possible. Without a massive increase in the development of renewable electricity supply up to the time corridor 2050-2070, this technology, as a contribution towards climate protection, is however not very practicable. In parallel to this important initiative, the basis of every action in the transport sector is to significantly reduce the specific energy consumption of each individual traffic platform to dampen the growth of transportation effort.The use of synthetic methane is practicable in view of the already widely available infrastructure.Natural gas has the potential of reducing the CO2 emissions in traffic due to its physical properties (C / H ratio): It increases the efficiency of Otto engines since higher compression ratios are possible; methane can also be produced synthetically. Natural gas represents a step towards greenhouse gas neutral transportation. The next step would be the fastest possible formulation of a globally effective strategy for the industrial production and use of electricity-based fuels from renewable energy sources (for example PtG-methane) and the direct use of electrical energy in the transportation sector. At the same time, directed further development of the technical processes needs to be initiated, unless other more realistic methods can be found how to achieve the 2-degree goal without having to use electricity-based fuels.”

When it comes to reducing the emission of CO₂ and pollutants in the mobility sector, electrified drivelines are currently a particular focus of public interest. Interest in the use of CNG as a way of reducing the CO₂ emissions of road traffic, however, is considerably less widespread. The commitment of most vehicle makers and their system developers is similarly low in respect of CNG.This paper shows that CNG vehicles are already making a significant contribution to the reduction of CO₂ emissions. Furthermore, a cross-sector analysis of the future energy market demonstrates that CNG is extremely well suited as a partner to the electricity market within the context of the energy transition. CNG vehicles are therefore the ideal addition to e-traction on the road to CO₂-neutral mobility.

The future of the combustion engine is currently under discussion. The future viability of high-performance engines for Sports Cars in particular is the subject of debate. Legislative requirements worldwide are subject to dynamic change, and there is also a significant shift in customer demands. Both of these factors must be brought into line with the Porsche brand philosophy – after all, Porsche Sports Cars have always been synonymous with tradition and innovation.The challenge for the future will be to meet these requirements with innovative technical solutions. Taking Boxer engines as an example, where does further potential exist and where do the conceptual advantages and disadvantages lie? In this paper we address the issues of combustion processes, exhaust gas aftertreatment, mechanics, fuels and electrification for Boxer engines by reference to examples.

Public discussion concerning the “Dieselgate” scandal creates the impression that the Diesel engine is at the end of its life and does not need further development efforts. In reality, the Diesel engine in passenger car and truck application is and will be realizing the major duties for transportation of passengers and goods.Current engines were developed regarding the former market requirements, i.e. with respect to the legislation boundaries of the last decade. In fact, in the last decades, a reduction in particle emission of about 99 % and about 20 % for CO₂ emissions has been realized (please also refer to Mollenhauer and Tschöke).Upcoming fuel consumption requirements and future legislation levels will force further improvement of consumption and emissions of Diesel engines. This implies test cycles like WLTP (Worldwide Light Duty Vehicle Test Procedure) for passenger car or WHTC (World Harmonized Transient Cycle) for truck applications, and furthermore also real world driving cycles in the future. In particular, Real World Driving Emission (RDE) monitoring requires a special focus for almost all vehicles equipped with Diesel engines in future. Furthermore, the discrepancy between test cycle and “real world” consumption in passenger car applications is a concern of vehicle users and authorities worldwide. For the application in trucks and other commercial vehicles (e.g. off-highway and agricultural machines), consumption under real world payload conditions is a major factor for business success of cargo companies and other commercial vehicle users. As a result, fuel consumption in most Diesel engine applications needs to be improved further, leading to drastically increased development efforts compared to the past decade of development.

Increasingly strict fuel consumption and emission legislation is forcing engine developers to use combinations of technologies that complement each other to produce high potential for cutting fuel combustion.For this reason, IAV has examined future-oriented technologies initially for their individual potential and then with a special focus on their complementary potential. The combination of geometrically variable compression (VCR) and early intake valve closure (EIVC) proved to be especially promising in early studies. It transpired that both technologies enhance the inner efficiency. It is worth noting that while early intake valve closure reduces pumping losses, it is detrimental to combustion quality and residual gas tolerance due to a loss of temperature and turbulence. This comes from the smaller tumble energy with the reduced valve lift and from cooling the cylinder charge under intermediate expansion to BDC.

Development of mobile propulsion technology is driven by fuel consumption and exhaust emission reduction. New gasoline powertrains currently developed at FEV address both these major trends using extreme lean combustion systems to combine best efficiency with lowest emission levels. This paper elaborates on the technology potentials and development methodologies used to handle challenges associated with gasoline lean burn.One focus lies on the definition of a central DI combustion system, which is capable for stable operation at rel. AFR of >1.9 and an outstanding thermal efficiency by charge motion and combustion chamber optimization based on FEV’s CMD approach. A further focus is put on the analysis of suitable boosting systems and stoichiometric- lean switching strategies, which is obtained here by a combined TC and e-charger system in combination with a two-step variable valve lift system. The performance of such system investigated in detail by gas exchange simulation including a comprehensive lean combustion model capable to predict cyclic combustion stability. Finally, the CO₂ and fuel consumption reduction of an extreme lean GDI engine concept is compared to an equivalent stoichiometric engine.

Whether being „the problem of the problems“, as Carl Benz called it, or the central, even eponymous component: The challenges as well as the chances of the ignition system have accompanied the past 150 years of SI engine development.Within this process the activities focused for a long time on the development of lowcost, robust and as maintenance-free as possible ignition components to assure, in context with the developments of the injection systems, a reliable engine operation under all climatic conditions. With rising awareness towards exhaust emissions and for this reason increasing legislative requirements, the functional demands on the ignition process increased considerably since the 1970’s. The legislative restrictions with respect to the emissions of pollutants – gaseous as well as particulate emissions- are continuously rising ever since. This is accompanied by the necessity of a continuously rising engine efficiency to meet the steadily more severe CO₂ fleet emission limits.The adaptations of the SI-engine combustion strategies as a consequence of these requirements, such as charge dilution or gas exchange strategies, often significantly impede the inflammability of the mixture. Thus, besides the measures for the generation of a higher level of charge motion, it is especially the optimization regarding the ignition systems, which allows an extension beyond the currently valid tolerance limits. Hereby, besides the stationary demands of the engine map, especially the necessities of the transient engine operation as well as the worldwide performance compliance have to be taken into account.Within our presentation the potentials as well as the limitations of various ignition innovations are discussed. We will look upon optimizations of the classical spark ignition, referring always to today´s serial solution, as well as upon alternative, spacious ignition systems. Besides the evaluation of the stationary potentials, especially the transient and realization relevant aspects will be illustrated. The resulting demands and potentials towards an automotive industrialization will be discussed.

One of the most promising technologies to increase efficiency and to decrease CO₂-emissions for future combustion engines is the utilization of exhaust gas heat through a Rankine cycle. A so called waste heat recovery system (WHR) converts the thermal energy of the exhaust gas into mechanical or electrical energy which can be used to propel the vehicle or to lower the generator load and thereby reduce the fuel consumption.Additional to the recovered electric or mechanic energy the engine can also benefit from the recovered heat, which can be regained through the condenser. The condenser can be connected to the coolant circuit where the heat can be used to improve the warm up of the engine and passenger cabin of the vehicle. This creates further potential to increase the efficiency of the whole system during warm up.The target of this study was to display the warm up behavior of WHR system and engine during cold start at different starting temperatures (0° to +20°C) under realistic conditions for different coolant circuit configurations. Preliminary investigations were performed to identify the appropriate coolant volume flow rates and circuit configurations to improve the warm up of the desired component. The resulting temperatures of the components and the fuel consumption of the whole system were the main focus points.The tests were conducted on a 4-cylinder 2.0 l SI engine which fulfils the EURO6 standard. A WHR system consisting of components as close-to-production as possible was applied. Engine and WHR system were put on a test bench which allowed lowering its chamber temperature down to 0°C.The results show that a Rankine WHR system is able to improve warm up of the engine and its components. The fuel consumption can be decreased due to the reduced warm up time while the cabin temperature can be increased. Power output seems not to be affected by the lower environment temperatures, which means a WHR system is able to provide even more benefits in efficiency for cold start scenarios.

From the perspective of legislative requirements on combustion engines in regards to exhaust emissions, CO₂-efficiency as well as higher specific loads from downsizing measures, friction reduction is especially important. Wear can over time affect the performance of components which for instance is likely to have a negative effect on the emission robustness of an engine. Under the new legislation for emission requirements the engine must meet the requirements over the lifetime of the engine. Deterioration in emission performance due to wear of components will have to be considered when setting the engineering target for the emission performance of the engine.In this context the APL Group is developing an energy based friction and wear model for predictive calculation of friction and wear in lubricated contacts. It allows for more focus on friction and wear related issues earlier on in the development cycle.

Predictive diagnostics introduces new service models to enhance the availability, to optimize maintenance intervals and to reduce maintenance time and costs of vehicles and machines.The article gives an overview about concepts and methods of predictive diagnostics.Predictive diagnostics has to be use system and component knowledge, combined with existing and new algorithm and vehicle and environmental data. Target of this service is the prediction of upcoming component breakdowns during daily operation using state based pro-files and optimization of the period inspection. With this information the vehicle driver, automobile manufacturer or fleet management shall be enabled to plan a maintenance window or an exchange of the affected component in advance. Thus an unplanned breakdown can be converted into a predictable maintenance event.

Engine manufacturers have to face stringent emission regulations worldwide while maintaining performance and drivability targets as high as possible. However, some strong paradigm shifts are still necessary to further improve the typical trade-off between fuel consumption and tailpipe emissions of Diesel engines.Split-of-losses analyses have shown that improvements in fuel efficiency could be obtained by optimizing the combustion timing and duration. More generally, this article aims at showing that a fully optimized heat release rate could help in increasing the efficiency while complying with NOx, noise and peak firing pressure constraints.The reference engine for this study is a 2.3L Euro-6 compliant engine used for light commercial vehicles and passenger cars. First, experimental heat release rates have been modeled for different operating points by spline functions using a reduced number of relevant parameters. Then, based on these parameters, numerous heat release rates have been defined thanks to a design of experiments approach. Engine performance such as fuel consumption, noise, NOx emissions and peak firing pressure have then been quantified on a 0D single cylinder engine simulation platform. To do so, a new two-zones combustion model has been developed, allowing the user to specify the heat release rate due to combustion while quantifying the NOx emissions.All these steps define a complete workflow which allows the optimization of the heat release rate in different operating conditions. Thanks to this approach, it has been shown that the fuel consumption could be reduced by 5.5% at 3000 rpm full load and by 2% at 2000 rpm middle load. Finally, these works do not only confirm that the NOx emissions and noise can be lowered by controlling the very beginning of combustion, but they also show that the fuel consumption strongly depends on the duration of the second half of combustion.

The future worldwide emission legislation is posing a challenge for the powertrain development especially in regards to emission reduction under real driving conditions. To achieve the targets a suitable development methodology, the usage of simulation tools and dynamic measurement equipment, as well as a detailed understanding of the physical phenomena and mechanisms are essential.For evaluation of a powertrain under worst case boundary conditions RDE cycles and synthetic cycles are generated on the basis of real driving data from stationary and dynamic analysis and implemented on the test stand by support of a simulation model for vehicle, cycle profile and different boundary conditions. As an example combustion process and calibration strategy in regards to mixture formation, fuel/wall film interaction were investigated due to RDE sensitivity. The calibration over the complete operating map relevant for RDE requires a systematic methodology with Design of Experiments (DoE). A significant influence as well as optimization potential was identified by investigating the influence of hydraulic and chemical characteristics of both, fuel and oil on the restriction of calibration parameters with regard to the target figures combustion efficiency, emissions and combustion stability. Depending on the specific formulation and even interaction of fuel and oil there is a significant restriction in combustion parameters, compromising combustion efficiency.The results show the influence on the particle formation based on an example with mixture formation parameters. Coming from the higher dynamic shares within real driving, new areas for optimization unfold, especially during transient engine. In order to comply with the future legislative boundary conditions, the quality and speed of the air and fuel path control must be realized with lowest possible spray-wall interaction.The APL Group has developed a complex chain of methods and tools with the focus on RDE capability. The basis is the repeatable implementation of representative real driving conditions on powertrain and engine test beds. The so gathered data is used for further analysis in regards to operation parameters and especially the interaction between fuel and oil formulation for holistic combustion process optimization.

Powertrain electrification is a key to compliance with future exhaust emission and CO₂ limits. Besides conventional 12 V systems and high-voltage hybrid architectures, 48 V mild hybridization offers significant fuel economy potential and advanced emission control without the need for an entire powertrain redesign. The 48 V power net enables high recuperation capability, improved stop-start functionalities as well as electrical boosting by an electric compressor (e-Compressor) or belt-driven starter generator (BSG).The paper summarizes the key findings of a joint project between FEV and Valeo investigating the potential of mild hybridization and electrical boosting for a downsized passenger car Diesel engine. The considered engine is the well-known FEV HECS concept in its third generation, consisting of a 1.6-liter 4-cylinder engine with single stage VNT turbocharger, e-Compressor, 48 V BSG and dual loop EGR. The engine has been installed in a D-segment vehicle with a dual-voltage electrical system and an advanced model-based engine control unit (ECU) developed by FEV. The paper focuses on the vehicle set-up and performance in transient emission test cycles and under real world driving conditions. In addition, electrical energy management was considered to ensure an efficient power distribution.

The next steps of fuel consumption legislation will require a combination of engine measures with various electrification measures, dependent on the vehicle segment, to reduce the energy demand targets of the vehicle. The introduction of 48V electrical architecture provides increased electric recuperation and limited electric driving at lower cost compared to full hybrid solutions, offering considerable fuel reduction potential in the WLTC.Current belt starter-generator systems (P0) already realise direct recuperation and torque boost functions. Additionally they can support a highly effective electrical supercharging system. More flexible powertrain architectures with a clutch to disconnect the engine form the driveline (P2,P3,P4) allow pure electric driving in a limited range, or simplification of the base engine towards the goal of a beltless engine. Demand controlled, electrical auxiliaries are already in series production for the cooling-, vacuum- or air conditioning systems. Additional areas of interest are the oil system and variable elements in the valve train or crank train.The optimum balance of electrical and mechanical functions on the base engine and its periphery requires an application dependent evaluation with the aim of minimized overall system complexity and cost as well as added customer value.In previous papers [13, 14, 16] this had been evaluated for a gasoline engine application.In this paper, the electrical efficiency potential of the 48V E-Motor is compared in different architectures and dependent on the electrical power. Furthermore the effects of friction and power loss of electrified components are investigated in detail for the relevant driving conditions. The implementation of the accessary electrification has been investigated for a conventionally optimized gasoline and diesel engine in a Csegment vehicle with the aim of a tailored 48V base engine and focus on modular functional integration.

To meet the many and various development targets in relation to CO₂, emissions, performance, comfort, weight and costs for 2025 and 2030, manufacturers are looking for the most sustainable scenarios in the context of fleet demands, modular systems and production costs. The powertrain plays a key role in this regard. Fundamental decisions have far-reaching consequences, and correcting those leads furthermore to an enormous effort. The complexity of the goals, demands and boundary conditions is so high that optimizing the powertrain’s components with conventional development methods is no longer sufficient.

The development of the optimal combustion process is a challenge engineers have been struggling with for a long time. The optimization of all the different hardware parameters like combustion chamber geometry, swirl, nozzle flow, number of nozzle holes, tip protrusion and so on, is a big challenge and is currently performed with the use of single-cylinder up to full scale engine testing. More stringent legislation on emission control, growing system complexity and variant diversity make it especially challenging to develop an optimum combustion system. Although tools like CFD are already well accepted and applied in the industry, there is still potential to better support the hardware development phase. Remaining efficiency potential needs to be exploited in an economic way. In this paper we present a new approach to combustion process development. With high speed CFD simulation a large number of different hardware combinations (tens of thousands) are calculated. The results of this huge parameter study are used to set up a multi-dimensional DoE model using AVL’s CAMEO tool. Finally the optimization within the model space for best fuel consumption / Soot emission trade-off can predict which hardware configuration is the most promising, but also which one should not be tested. Finally a validation on the test bed is required. By using this novel approach the most promising hardware for optimal combustion can be found swiftly and efficiently. This reduces the time required at the engine test bench thus significantly reducing the costs while allowing more parameters to be investigated.The piston bowl and fuel injection system defined by 3D CFD was tested by VCC (Volvo Car Cooperation) on a single cylinder test bed and the findings of the CFD based layout could be confirmed.

One main focus in vehicle development is CO₂ reduction (Figure 1). In order to meet this goal a further increase in engine efficiency will be required. The optimization of the combustion process will play an important role. Therefore combustion influencing parameters like valve angle, intake port layout, piston surface and combustion chamber layout need to be optimized. Upcoming efficiency technologies for gasoline engines, e.g. Exhaust Gas Recirculation (EGR), Miller cycle, etc. will drive new, more challenging requirements for the combustion system. A fundamental understanding of the correlation between geometrical and combustion performance data is essential and will require a sophisticated development process comprising extensive 1D- and 3D-simulation, component testing and complete engine testing.

The number of mechatronic systems on-board motor vehicles has risen sharply in recent years. Increasing connectivity, integration of new functions and ever more stringent demands in terms of CO₂ reduction have driven this trend and focused attention on future requirements in automotive development.Digitization, urbanization and sustainability are the new strategic factors which are shifting the focus to the development of electrified systems, thereby closing the gap between conventional combustion engines and efficient high-voltage vehicles.An intelligent, highly interconnected drive train and operating concept as the enabler of new, future-proof CO₂ reduction functions combined with a substantially higher powered electrical system with more intensive functionality is needed and is being introduced into series production.The cost of such a new concept needs to be less than that of a high-voltage system, and the concept has to offer more functionality than a conventional present-day vehicle.These are ambitious goals, demanding extensive convergence of the drive train and the energy network. The groundwork has been laid for the integration of the 48 V system.This new voltage level, which is characterized by higher power and improved storage capacity, is increasingly attracting attention for applications beyond the drive train. Chassis control systems, such as electric roll stabilizers, or consumers such as electric drive compressors are also enjoying the superior performance and the new possibilities that are opening up.Consequently, energy-intensive functions to reduce CO₂ emissions are coming up against output-intensive control systems delivering high dynamics. The delicate balance required is analyzed and the scalable solution variants are presented.An intelligent operating strategy ensures an energy equilibrium within the vehicle and combines efficiency with driving experience. Yet the route to a production-ready power system topology for the broad range of vehicle concepts entails detail aspects which are often neglected.Issues such as crash safety, availability of supply to safety-related components and cross-system connectivity are proving highly complex, and demand a degree of process discipline in view of the need to rollout functionality across entire model series with different engine / transmission variants in a wide variety of different countries and specifications.An interdisciplinary approach is needed in order to spread the multiplicity of new tasks and focus concerted efforts on the shared goal. Cross-functional testing and integration planning, extending as far as closely linked functional and expert teams, must be established in order to progress a sustainable global electrification strategy to production maturity.

The first vehicles were not equipped with an electric supply distribution system: starting was assured by hand cranking, lights were oil laps and the function of the horn was assured by a bell.In the 1920s electric cranking was introduced with the use of 6V batteries whose positive terminal was connected to the chassis of the vehicle. The transition to 12V batteries was started in the 1950s due to the increased power requirements induced by the use of engines with more displacement and a higher compression ratio.

In recent years, Greenhouse gas (GHG) reduction has become the major driver for new technological developments in the transportation sector since CO2 emissions emitted by vehicles represent a significant part. In Europe for example, Greenhouse gases produced by Road Transportation comprise about 20% of anthropogenic CO₂, which is only 5% less than the biggest contribution coming from Heat and Electricity production. Although GHG emissions in Europe tend to go down, further efforts have to be undertaken in order to reduce the CO₂(+CH₄/N₂O)-concentration in the atmosphere even more in order to limit global warming. For 2030, the European Commission has targeted a CO₂- reduction of 40% compared to 1990 levels which also implies a stepwise reduction in fleet-averaged CO₂ levels for newly registered passenger car vehicles. In 2021 therefore a fleet average of 95 g/km was fixed which would correspond to 4.1 litre gasoline or 3.6 litre Diesel per 100 kilometres. Due to thermodynamical limitations, those numbers will not be achievable with conventional Diesel and Gasoline-based powertrain technology alone, which implies the necessity for OEMs to develop and apply new technology in order to provide sustainable, profitable and attractive vehicle solutions. Beside disruptive powertrain solutions such as battery electric vehicles, which require high investments in production and infrastructure development, there are also new more evolutionary powertrain concepts based on Low-Carbon-fuels, which do have a lot of promising features. If those new fuels are carefully selected, existing powertrain technology could be preserved with small modifications in fuel and tank system, which of course would strongly reduce required manufacturing investments. Even vehicles, which are already on the market could contribute to a sustainable mobility if the chosen fuels are compatible with conventional powertrain technology,

In commercial vehicle applications, particularly in the heavy-duty long-distance traffic use, the internal combustion engine is expected to remain a dominant engine type in the medium term. Beside high cruising range with moderate weight, the performance and torque characteristics are the decisive properties of today’s Diesel engines.With respect to global CO₂ targets, natural gas in commercial vehicle applications could play an increasing role. Compared with Diesel it provides a theoretical CO₂ advantage of 25% based on the C/H ratio of the fuel. Furthermore, improvements for regenerative production of natural gas are on the way that could further improve the CO₂ balance of natural gas combustion engines. However, due to the lower cycle efficiency, today’s state of the art natural gas engines based on a spark ignited Otto combustion principle, do only partially achieve the theoretical CO₂ benefit compared to Diesel engines. Furthermore, higher thermal load and disadvantages in the transient behavior have to be taken into account.

Natural Gas (NG) is an abundant and affordable energy carrier that is widely used in the power and heat sector. NG also offers attractive opportunities as a transportation fuel due to its lower carbon to hydrogen ratio and its ability to burn with relatively low local emissions in combustion engines.The paper gives an overview on NG resources and availability, as well as the options to utilize NG in transport. Natural Gas can power mobility in different ways: as compressed Natural Gas (CNG), as liquefied Natural Gas (LNG), as gas-to-liquids (GTL) but natural gas can be used as well to produce hydrogen or electricity as fuel for fuelcell electric or battery-electric vehicles. The paper explores the various possible fuel pathways. The paper covers the following mobility sectors: light duty (passenger cars) and heavy duty (on-road goods transport).The pros and cons of these pathways will be described in more detail covering the criteria Well-to-Wheel (WtW) efficiency, WtW greenhouse gas emissions and CO₂ abatement cost.

Future mobility based on internal combustion engines has to face two important sustainability issues. One is the environmental impact of fuel production and combustion, the other is the long term availability of fuel stocks. An important contribution to solve these problems can be given by the use of synthetically produced fuels, made out of recycled carbon dioxide (CO₂) [Ma10, Ma12, Ma14] and renewable energy [Ce09]. These fuels help to alleviate the problems both of storing renewable energy and reducing the emissions of greenhouse gases in the transport sector. For the latter, different scenarios have been investigated where power-to-liquid fuels will play an important role to reach the goal of the European Union, to reduce overall CO₂ emissions by 80-95 % until 2050 in comparison to 1990 [Be16, Sc15].

With an ever-increasing demand for fuel and a scarcity of existing crude oil resources as well as a desired elimination of greenhouse gas emissions in the transport sector by 2050, research on alternative fuels is gaining in importance. In addition to the further development of combustion engines and their exhaust gas aftertreatment systems, particularly climate-neutral fuels and their production offer great potential for fulfilling the CO₂ emission and pollutant emission requirements.

The paper is referring to various 2016 publications about the power to liquid (PtL) technology and shows the high technology readiness level of the technology. It shows the main energy balance and the carbon footprint of a PtL plant for the production of 100,000 annual tonnes of methanol or 42,000 annual tonnes of gasoline in Norway. It discusses the ten year history of methanol and gasoline pricing and is giving the techno-economic discussion of the described plant in Norway.

Electricity-based fuels are a missing link in an energy system between the electricity sector and the transportation sector. The electricity sector worldwide is undergoing a remarkable change. Since 2012, new additions in renewables overtook additions in fossil and nuclear power generation capacities1. In 2015, global investment in new renewable power capacity, at USD 265.8 bn, was more than double the USD 130 bn allocated to new coal and natural gas fired power plants2. Renewables outpaced fossil fuels regarding capacity additions and investments. Due to the increasing commitment to carbon emission reduction, climate change mitigation is now a worldwide target. The Paris Agreement entered into force on 4 November 2016 after countries responsible for an estimated 55 % of the total global greenhouse gas emissions (including China, the USA and the European Union) have ratified it. Political measures that reduce emissions (e.g. subsidies and tax reduction for technologies, bans for other technologies, CO₂ pricing) will probably increase in the most important markets. There will be a further clear trend towards renewable power generation technologies, and solar photovoltaic and wind generation will dominate the market for new capacity additions.

It is now widely accepted that CO₂ and other heat-trapping gasses released into the atmosphere by human activities are driving a global temperature rise that, if unchecked, could result in severe damage to natural and human systems [1]. The urgency of deep decarbonization of the U.S. economy is now clear and several renewable energy technologies are approaching cost parity with fossil fuels. However, debates around the requisite rate of reduction, and the form of regulations that can achieve those reductions fairly and cost-effectively have resulted in near inaction. Typical studies of the GHG reduction pathways rely on multiple sets of assumptions including a fixed trajectory for reduction in GHG emissions (a ‘glide-path’) designed to achieve a chosen representative concentration pathway (RCP, the actual atmospheric concentration of GHG) [2, 3], costs of technology alternatives and some form of model for technology selection and deployment. These models seek to minimize total cost (net of taxes and incentives) within other constraints [4-7]. As a result, such models are highly informative as to what technology pathways might be effective in meeting the stated goals (given the model assumptions) but are far less informative in regard to how precisely a given regulatory concept – which cannot ‘know’ the future or change personal preferences – will steer technology choices along a preferred pathway.

The introduction of the Stage V emission legislation requires a Particulate Matter (PM) filtration due to the Particle Number (PN) limit.The main objective of FPT’s Stage V development was to maintain the proven benefits of the high efficiency SCR-only technology implemented for Stage IV (HI-eSCR). In particular this involved low fuel consumption, compact and maintenance-free design as well as an overall robust layout.FPT integrated the filter function on the SCR (SCR-F) in cooperation with catalyst and substrate suppliers to meet all these challenging objectives. During the development further challenges as the reduction of SCR performance due to ash loading as well as the soot regeneration had to be tackled.FPT’s HI-eSCR2 for Stage V reaches all emissions targets while maintaining the muffler volumes and canning designs of Stage IV.A description of the HI-eSCR2 concept for Stage V as well as the development challenges are described in this paper.

The application of highly integrated exhaust aftertreatment systems like SCR-coated Diesel Particulate Filters (SDPF) allows both a reduction of required package space and functional advantages [1] like a further reduction of tailpipe emissions compared to conventional systems. In particular for engine cold start, earlier AdBlue/DEF dosing and thus reduced tailpipe emissions can be achieved by improving system heat-up through bringing SCR functionality further upstream within the exhaust aftertreatment system [2].In this report specific interactions resulting from integration of multiple functionalities on a single system component are investigated in detail and discussed regarding system aspects. One key trade-off arises from competing chemical reaction mechanisms involving nitrogen dioxide which is consumed on the same component by passive soot oxidation on the one hand and the fast SCR reaction on the other, the latter being significantly favoured due to faster reaction kinetics [3].As a consequence, it is shown that the passive regeneration capability of the accumulated soot is seriously inhibited with increasing SCR efficiency. A safe and stable passive regeneration can solely be achieved for applications running on high engine loads.Means by which this fundamental trade-off between safe filter regeneration and high NO_x reduction rates can be handled for future heavy duty diesel applications, optimized operation strategies and advanced system configuration, are identified.

Globally small industrial engines in the range from 2.5 to 4.5 liter displacement play a major role for construction, agricultural and other industrial applications. As shown in Figure 1 the number of emission regulated industrial engines today is still comparable small as especially in Asia and other emerging markets the emission requirements are still limited. Today SCR systems for these small engines just have been introduced and are causing several disadvantages to these applications, like space requirement, need for an infrastructure for a second liquid and additional sensors and actuators which cause some risk to reduce the robustness of these engines and at the same time increase the cost. A significant number of industrial engines in the Asia region will sooner or later require a simple and robust emission reduction technology which is easy to apply to many different applications.

For current and prior emission legislations, the focus of the development process was strongly influenced by achieving the limited emissions components like nitrogen oxide (NOx), particulates, etc. In future, the focus will be on improving the thermal efficiency and consequently reducing CO₂ emissions. For the already existing greenhouse gas legislation in the USA as well as the discussed CO₂ regulation in Europe, both measures on the vehicle (aerodynamics, tire rolling resistance, axle efficiency …) as well as measures on the power train will be mandatory to achieve the future limits. As an example: For the second phase of the greenhouse gas engine standards in the US there will be a reduction of up to 6.1% respectively, 5.1% considering same weighting factor in RMC for MY2027 compared to MY2017 required.

Commercial vehicles require continual improvements in greenhouse gas emissions to meet upcoming emission regulations and fleet fuel economy needs. Challenges for future emission standards require technologies for engine exhaust temperature management to deal with low engine load operation for optimal aftertreatment performance. The proposed ultra-low NOx emission standards of 10% of today’s US level (0.2 g/hp-hr) is challenging and requires significant temperature management strategies including heat-up strategies during the cold part of the emission cycle. Heavy duty commercial vehicle applications requires a heat source on the order of 30 kW to achieve aftertreatment temperatures for sufficient NOx reduction. There are technologies that can provide such high heat loads in a short period of time. A diesel exhaust burner is an option for fast heat-up at the expense of fuel economy. Variable valve actuation (VVA) solutions are effective for aftertreatment temperature management including early exhaust valve opening, intake valve closing modulation and cylinder deactivation. Further steps of emission legislation focus on in-service operation, including NOx emission reduction during low load operation. Such low engine load operation may result in exhaust temperatures between 100°C and 250°C, where NOx aftertreatment systems are not effective. Thus, technologies are needed to raise the exhaust temperature under such conditions. The use of VVA to vary the air-excess ratio in the cylinder is a fuel efficient method to increase exhaust temperature under low load conditions. Methods of intake air throttling are capable measures such as cylinder deactivation and Miller cycle. Cylinder deactivation during low load engine operation shows a marked increase in exhaust temperature by approximately 100°C which moves aftertreatment systems to a more optimal region, typically significantly above 250°C while also offering fuel economy benefits. The addition of a high efficiency boosting system enables Miller cycle operation to improve fuel economy. Thus, the use of VVA is a leading technology combining the future requirements to simultaneously reduce NOx and fuel consumption. This paper will show the benefits of variable exhaust valve opening, intake valve closing modulation with and without boosting, and cylinder deactivation for meeting future emission regulations and fuel economy needs. Finally, solutions combining VVA and engine braking are provided.

Reducing the total costs of ownership is a major goal during the development of commercial vehicles. Broken down into objectives with respect to the engine, this is synonymous with a decrease in fuel consumption while meeting the requirements regarding durability and market-specific exhaust-emission legislation. The adjustment of the charging system to the thermodynamic and mechanical boundary conditions of the engine is of great importance to fulfill the development targets.

Reducing fuel consumption still is a major driver in the development of engine and powertrain solutions for commercial vehicles. Especially in vehicles for long-haul operation, fuel cost is the most significant contribution to the overall cost of operation for the owner. Potential future CO₂ charges will further increase cost pressure and give the added incentive to operate efficient vehicles. Within the powertrain, hybridization and thermal management are two crucial topics to improve fuel efficiency.

Commercial vehicle engine efficiencies continue to increase due to friction reduction, combustion refinements, and air path improvements. This drives the cost per efficiency gain upward. As this occurs, waste heat recovery (WHR) becomes appealing as a solution for lower CO₂ emissions, addressing legislative and economic pressures. Distributing this harvested energy through a 48V mild hybrid architecture allows it to be immediately reintroduced to the vehicle powertrain or stored for future use. Likewise, a 48V infrastructure grants additional gains by electrifying accessories and enables the use of electrified turbomachinery such as an eTurbo™, eBooster®, or electric turbocompound system.One solution for exhaust WHR is the organic Rankine cycle (ORC). Ethanol was chosen as the working fluid in this research for its thermodynamic properties, low global warming potential, cost advantages, and low toxicity.Simulation and testing have demonstrated the expansion device is the key contributor to ORC system thermal efficiency and economic viability. For this study, a turbine expander was developed, realizing high thermal efficiency, large expansion ratio, wide operating range, mechanical simplicity, small package volume, and low mass. This design comprises an oil-free bearing system which eliminates the need for lubricant to be suspended in the working fluid, increasing system output and diminishing heat exchanger contamination risk. Also included is a shaft-coupled, high pressure pump which eliminates the cost and complexity of a separate device. A high speed electric machine is built into the expander, which, using a proprietary power electronics controller, distributes recovered energy to a 48VDC electrical bus. This paper details the decisions which took this machine through three generations of hardware development and two years of testing on an engine-coupled ORC system.One of the most difficult decisions in implementing waste heat recovery is selecting the method by which recovered energy is transferred back to the vehicle. This paper discusses the implementation of the above turbine expander/generator into a 48V mild hybrid system which integrates the WHR with a battery that acts as an electrical storage buffer. This stored energy is delivered back to the vehicle drivetrain via a motor/ generator capable of assist and regeneration coupled to the front engine accessory drive (FEAD).

With the introduction of EURO VI emission legislation, many innovations in the cooling system and its components became necessary to deliver the increased cooling performance requirements without an increase in fuel consumption. Some examples are radiators charge air coolers and EGR coolers with a high performance density, new fan actuators with improved control capabilities and, for the first time, a Visco actuator for the coolant pump. Whilst the components and there interaction got optimized, the principal architecture of the cooling module was, except some few exceptions, the same as originally introduced in the 1980s: The direct cooling system. In this system the individual cooling tasks are cooled directly in individual components by cooling air. This is typically the HVAC condenser, the charge air cooler and the radiator.

The expected growth of trade is a major challenge with regard to environmental sustainability. Especially in urban zones more distribution traffic will further worsen the local pollutant situation. Electrically driven distribution vehicles as part of low-carbon city mobility concepts can be one answer to this challenge. Based on requirements and boundary conditions of a typical distribution vehicle, representative load profiles and the demands for the electrical system are defined, leading to a power requirement for the traction motor of 150 kW and battery capacity which shall support at least 100 km of electric range. To cover longer distances of up to 200 km per day, different range extender powertrain configurations with combustion engines and also a fuel cell system are discussed in a simulation study, while the pure electrical vehicle with 200 km range is investigated for comparison. This results in investigating overall seven different vehicle configurations, covering energy consumption as well as package and costs aspects. The investigation shows that a benefit in fuel consumption is possible with all the range extended vehicles compared to the conventional vehicle. A benefit in operation cost and therefore a return of invest is highly depending on the daily mileage and prices for energy.

For enlarging the usability of electric locomotives an integration of the Diesel Power Module (DPM) into a customer locomotive was performed. The described paper represents the introduction into hybridization of E-locomotives for enlarging the existing product platform. STEYR MOTORS and SIEMENS MOBILITY therefore developed a complete aggregate with high performance density considering existing interfaces and normative requirements. As producer of high performance diesel engines for special applications STEYR MOTORS achieved high competence in delivering sub systems like the Diesel Power Module for rail applications.

Increasing market requirements regarding the lifetime expectation and reliability of combustion engines will lead to a part-replacement of passenger car engines in commercial applications.Because of this market segment’s cost sensitivity, there is the need for engines that will fulfil the requirements of being both highly reliable and durable, as well as cost efficient.

There are three different displacements of Mercedes-Benz heavy-duty engines available. The OM 470 with 10.7 l, the OM 471 with 12.8 l and the OM 473 with 15.6 l displacement, all six-cylinder in-line engines.

The death of the combustion engine and the timing of its passing have been predicted on numerous occasions, most recently as a result of the ongoing diesel emissions scandal. The fact remains that currently there is no comprehensive alternative that is energy-neutral, can deliver regardless of demand, and offer the potential to fully replace the conventional engine. However, a variety of electrification technologies – from 48 volt mild hybrid systems up to full hybridization – can deliver improved efficiency from the combustion engine. Another strategy demonstrates a zero-emission vison by powering conventional engines using synthetic fuels gained from renewable sources such as DME.

Upcoming most stringent legislations for greenhouse gas emissions (GHG) as well as for criteria pollutant emissions will confront the commercial vehicle industry with new challenges. The recently concluded 2nd phase of GHG regulation in North America demands a GHG reduction of up to 27% of for model year 2027 (MY2027) depending on the individual application. This regulation includes a dedicated reduction of CO₂ emissions from engines, e.g. in the magnitude of 5% for heavy heavy-duty tractor applications. At the same time, the California Air Resources Board (CARB) announced plans to introduce a 90% reduction of nitrogen oxide (NO_x) emissions compared to current levels (EPA10). In addition, EPA announced plans to lower the nationwide NOx standard. In Europe, a reduction of NO_x emission limits is a possible development for the future. A mandatory CO₂ declaration for heavy-duty vehicles will be in force in the EU from 2018. Based on the outcome of the monitoring, CO₂ limits could follow at a later stage.Engine and vehicle manufacturers need to investigate possible approaches to be able to fulfill the upcoming most stringent regulations as well as being competitive in those two major markets.It needs to be investigated to which extent new technologies are required, in parallel to a more evolutionary approach, and how the optimum future setting would look like.The combination of technologies will highly depend on the targeted branding and the product positioning.The product positioning will then determine the importance of attributes as product cost, weight, packaging and performance.