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2024 | Buch

Internationaler Motorenkongress 2022

Mobilität und Fahrzeugkonzepte von morgen


Über dieses Buch

In diesem Tagungsband werden von anerkannten Experten der Automobil- und Nutzfahrzeugbranche eine Fülle neuer technischer Lösungen aufgezeigt.

Die Tagung ist eine unverzichtbare Plattform für den Wissens- und Gedankenaustausch von Forschern und Entwicklern aller Unternehmen und Institutionen.

Der Inhalt

Klimagerechte Verbrennungsmotoren aus globaler Sicht.- Gesamtsystem Verbrennungsmotoren und Kraftstoffe: CO2-Neutralität, Emissionen, Elektrifizierung.- Nutzung von Wasserstoff und synthetischen Kraftstoffen.- Sektorübergreifende Lebenszyklus-Betrachtungen.

Die Zielgruppen

Fahrzeug- und Motoreningenieure sowie Studierende, die aktuelles Fachwissen im Zusammenhang mit Fragestellungen ihres Arbeitsfeldes suchen - Professoren und Dozenten an Universitäten und Hochschulen mit Schwerpunkt Kraftfahrzeug- und Motorentechnik - Gutachter, Forscher und Entwicklungsingenieure in der Automobil- und Zulieferindustrie

Die Veranstalter

ATZlive steht für Spitzenqualität, hohes Niveau in Sachen Fachinformation und ist Bestandteil von Springer Nature. Hier wird unter einem Dach das Know-how der renommiertesten Wirtschafts-, Wissenschafts- und Technikverlage Deutschlands vereint. VDI Wissensforum vermittelt als ein führender Weiterbildungsspezialist das Wissen aus praktisch allen Technikdisziplinen und den wichtigsten außerfachlichen Gebieten. Dabei wird großer Wert auf Nachhaltigkeit und Praxisrelevanz gelegt.


Reduction of catalyst purge air mass flow at overrun fuel cut-off as an alternative to torque neutral combustions
The following paper introduces a new approach of reducing the purge air slip during overrun phases with fuel cut off to keep the three-way-catalyst near its operating range for the following tip-in, as an alternative to late combustions at zero load with high specific fuel consumption. Therefore there are investigations at a gasoline engine with electromechanical camshaft phase actuation in a wide range presented, that show a significant reduction of the air mass flow at overrun without engine stopping. Using the camshaft actuation the flow and the oxygen concentration over time in the exhaust system are controlled via the measured throttle pressure ratio and the exhaust oxygen sensors. To achieve a noticeable and reproducible reduction in nitrous oxide and carbon monoxide tailpipe emission concentrations at tip-in, the flow has to be reduced quickly towards zero to keep the oxygen concentration low in the exhaust aftertreatment system, while the hydrocarbon tailpipe emission concentration remains at the reference level. The presented observations are pointing out key points for a derived cascaded controller structure.
The presented investigation is part of the author’s doctoral thesis program at Mercedes- Benz AG in cooperation with the ILS at TU Berlin.
Thomas Pausch
Turbo Compressor for Efficient High-Pressure Air Supply in Catalyst Heaters
The expected requirements of future emission legislations for internal combustion engines (ICE), like EU7, require a very short start-up time of the emission reduction systems in the exhaust after treatment and an effective operation of these systems in all driving conditions. The critical aspect for effective operation of the exhaust after treatment system is to run the catalyst above the so-called light-off temperature. It is therefore necessary to reduce the time to reach light-off temperature during engine start-up. For periodically activated systems, especially in hybrid powertrains where the catalyst cools down during electrical drive modes, it is also necessary to maintain light-off temperature.
To overcome these challenges, the potential of in-cylinder exhaust thermal management approaches is limited and external measures like secondary air injection (SAI), electrically heated catalysts (EHC) or fossil fuel burners (Burner) are required. These different external solutions have unique advantages and requirements for the air supply system. The air supply units are faced with challenging requirements concerning mass flow, pressure ratio, and installation space. The three systems SAI, EHC, and fossil burner are compared in this paper and the requirements for the necessary air supply are derived. Possible solutions for the corresponding air supply units are investigated and compared.
Jens Löffler, Mario Staiger, Benjamin Dietz, Ahmet Çokşen, Sönke Teichel, Philipp Handschuh
Why internal combustion engines and fuel cells will both play a role in a future hydrogen society
The transport sector is facing stringent greenhouse gas (GHG) reduction targets in all regions around the globe. The use of green hydrogen as an energy carrier is expected to play a key role in the defossilization of the transport sector. This will be enabled by technological advancements and the plans of various national governments to establish a broad hydrogen supply infrastructure. Especially for medium and heavy commercial vehicles, hydrogen fueled powertrains can become an attractive and competitive zero-emission solution.
In this publication, FEV compares the competitiveness of fuel cell (FC) powertrains with hydrogen internal combustion engines (ICEs) for various use-cases. For commercial vehicles, the total cost of ownership (TCO) is a key purchasing criterion. But further aspects such as payload, uptime, interoperability, access to low/zero-emission zones, etc. are also relevant to assess the competitiveness of a powertrain solution. Against these criteria, vehicles powered with fuel cells and hydrogen internal combustion engines are analyzed to forecast their market relevance towards 2030 and beyond.
In addition, the possibility of retrofitting hydrogen-based powertrains into “conventional” commercial vehicles as a means of defossilizing the existing vehicle fleet is being investigated.
Thomas Lüdiger
Experimental investigation of a hydrogen powered heavy-duty truck engine
A baseline HD diesel truck engine is converted to a port fuel injection hydrogen engine. Dedicated components, developed for this application proved to be suitable in this full engine run. The paper focuses on thermodynamics investigation and crankcase ventilation. The performance target of > 80% of the baseline engine is achieved with 20.5 bar BMEP and 315 kW peak power. A very good thermal efficiency, similar to that of the baseline engine, is demonstrated with > 44% in significant areas of the map. Second main topic is MAHLE’s solution to ensure uncritical hydrogen concentration in the crank case. An active ventilation system, including the High Pressure Impactor (HPI) component, uses scavenging with ambient air to ensures safe hydrogen concentration levels. Its development was aligned with the hydrogen PCU applied, with in turn is optimized for good blowby performance.
Daniel Rieger, Florian Mayer, Fabian Weller, Simon Schneider, Roman Stiehl
Multi-dimensional knock control for lean operating HICEs
A carbon-free drive concept must be established as a long-term solution for meeting the climate targets. The hydrogen-powered internal combustion engine (HICE) represents a robust, cost-effective and CO2-free option. Therefore it can make a significant contribution to the transformation of the transportation sector.
The unwanted self-ignition of the mixture that occurs in gasoline engines is also relevant in the HICE. But the underlying combustion process offers several opportunities to optimize the conventional knock control strategy. Instead of reducing the knocking tendency by means of ignition angle retardation, which entails disadvantages in combustion efficiency, a multi-dimensional control concept was developed. This is based on the adjustment of the air-fuel equivalence ratio for each individual cylinder and the overall exhaust gas recirculation rate. The ignition angle retardation is still available as a fallback level, which is used when the other two intervention parameters have been exhausted.
The advantages of the new control method are demonstrated with the aid of tests on a real engine and a comparison with a conventional knock control. Besides slight efficiency advantages and an effective reduction of the knocking tendency, the flexibility of the application and the adaptability of the control method to the prevailing conditions increase.
Daniel Thomas Koch, Benedikt Judt, Alvaro Sousa
FVV Fuels Study IV – Transformation of European Mobility to the GHG Neutral Post-Fossil Age
In the new FVV Fuels Study IV altogether 42 technology (energy/fuel – powertrain) pathways (100% scenarios) - which all lead to carbon neutral mobility in 2050 - are compared, with regard to energy demand, total costs, cumulative greenhouse gas emissions and other environmental impacts. Unlike numerous other studies on the same topic, a holistic cradle-to-grave approach is chosen, that considers all relevant costs and emissions from vehicle production and the setup of a sustainable energy supply system to use and recycling. For this purpose, the emissions caused by the construction of the infrastructure, such as wind turbines, electrolysers or charging stations, were also included. With this approach, the cumulative emissions up to the year 2050 are examined for six different energy sources, seven different powertrain technologies (on three different vehicle efficiency levels) and for two energy sourcing scenarios (domestic and international). This is because valid insights can only be obtained by integrated simulations of the entire energy system.
Regardless of which of the 42 technology pathways for new vehicles Europe chooses, the 1.5°C greenhouse gas budget set for Europe will already be exceeded by 2032 due to transport emissions alone, with the already challenging assumed ramp-up speed of carbon neutral technology (determined by the vehicle fleet exchange rate). The reason for this is the dominant share of the existing fleet using fossil fuels, phasing out by 2050, in total emissions. Irrespective of the scenario, this amounts to around 70 percent at an identical rate of introduction of defossilised vehicle technologies and accordingly replacing fossil energy in transportation at the same rate. Without technology options that reduce emissions in the existing fleet, it will not be possible to achieve the ambitious European climate targets.
Ulrich Kramer, David Bothe, Frank Dünnebeil
Fulfilling fuel specifications and resulting challenges of refuels
Immediately effective CO2 savings can only be achieved in the existing vehicle fleet. For this reason, it is important to produce drop-in fuels in accordance with the current quality standards EN228 and EN590, which have a high regeneratively produced content. Within the project "reFuels- rethinking fuels" both BtL- and PtL-fuels are produced and investigated in a holistic manner. In this study, the focus is on the use of gasoline fuel, which is within the valid EN228 standard and has a regenerative content of 40%. The fuel, called G40, has an octane number higher than 100 as a relevant difference to conventional gasoline.
The regenerative content of 40% is achieved by using 10% EtOH and 30% bioliq®. An improved bioliq® batch with reduced >C9 aromatics content was used. In previous studies, the increased aromatics content led to slightly higher particle emission, but this could be corrected with the improved batch.
Characteristic engine map measurements were performed in single-cylinder tests. As expected, the fuels behaved very similarly, with the influence of the octane number and the increased ethanol content compared to the E5 reference.
In ICE cold start tests down to minus 7°C, the fuels therefore behave very similarly. There are slight advantages of the G40 in WLTC and RDE cycles with regards to the particle count. All tests revealed that G40 could replace conventional gasoline fuel without restrictions.
Thomas Weyhing, Mitra Zabihigivi, Olaf Toedter, Uwe Wagner, Thomas Koch
Synthetic Fuel Detection for Vehicles in Field using Machine Learning
In order to achieve the EU-wide climate targets and to realize the full CO2 savings potential, a reliable in-vehicle fuel type detection is inevitable. We developed an appealing solution for fuel type detection, which is inexpensive and robust. Our software approach uses existing hardware of diesel vehicles and can be integrated into standard engine control units, thus allowing retrofitting of vehicles in field. As a novelty, our approach uses the fuel temperature as the most important distinguishing feature and is based on several machine learning methods. For our research we used a large endurance run data set of Hydrogenated Vegetable Oil (HVO) and diesel fueled vehicles. We modeled numerous sensor models using time series regression analysis and calculated the differences between model outputs and the actual sensor values. These differences are the main input for our fuel type classifier, which is a feed forward neural network. Moreover, we developed a filtering method using the neural network output probabilities and a one-class-SVM to enhance the robustness of the fuel type detection. Our approach achieves an overall accuracy of 97%. To the best of our knowledge, our approach allows for the first time distinguishing HVO and diesel without additional hardware.
André Bojahr, Hilko Janßen, Nils Paetsch
Passive Pre-Chamber Spark Plug Development, Optical Analysis and Mass Production Feasibility
Prechamber ignition is a means to further optimize the internal combustion engine in terms of knock resistance and thus efficiency. The flame plumes emitted by the prechamber lead to a faster flame propagation especially to the outer circumference of the combustion chamber.
The paper describes the development and the features of this passive pre-chamber spark plug including layout, CFD simulation, thermal simulation and testing up to a prototype vehicle. Specialties like AVL’s residual gas chamber, which allows zero load operation, are described.
Together with Tenneco a production feasible solution of this passive pre-chamber is developed. The way from the prototype to the functional production feasible part is described. Design features as well as simulation results are described. A specific part of the paper is reserved for optical analysis of prechamber spark plugs as this represents a straightforward tool for developing against some deficiencies allocated with prechamber spark plugs such as catalyst heating, starting and low load operation.
We report on some principal thermodynamic and visual analysis of ignition and flame propagation in a passive PC system with documentation of ignition and combustion behavior including the limits of ignitability and misfires.
High load operation, on the other hand, needs to observe limits arising from PC component temperatures. Here, thermal imaging of the pre-chamber’s internal surfaces and especially the spark electrodes, provides understanding of temperature limits and gives guidance for well controlled thermal conditioning of the PC’s contacting surfaces.
Marko Certic, Peter Janas, Paul Kapus, Harald Philipp, Ernst Winklhofer, Daniel Hilbert, James Lykowski, Matthias Neubauer
Comparison of DOC-based vs. NOx storage-based aftertreatment architectures as related to pollutants conversion efficiency and GHG impact
Besides reaching lower tailpipe emissions, upcoming regulations are likely to require lower CO2 values and, at the same time, limit other GHG (such as N2O and CH4) over RDE cycles. Focusing on light commercial vehicles, the present work will show a comparison (relying on an extensive testing campaign) of aftertreatment architectures based on DOC and NOx trapping coupled with SDPF. Strengths and weaknesses of the different architectures will be highlighted with special regard to GHG contribution as related to aftertreatment efficiency.
Chiara Pozzi, Giuseppe Previtero, Luisa Cusanno, Rahul Mital
Investigations on the Impact of Urea-Dosing on Particulate Number Measurement for Heavy-Duty Applications
This paper addresses the influencing parameters of the generation of urea-based nano-particulates on top of engine-based soot emissions. Steadystate and transient engine operation studies show that the urea mass-flow and the exhaust temperature have the most significant impact on the formation of those extra particles. The number of those particulates correlates proportionally to the injected urea mass-flow with a major share of diameters below 23 nm. Injection parameters such as pressure or nozzle geometry show only a minor influence on the particle formation. To some extent the emissions are influenced by the aftertreatment layout with parameters like catalyst volume, cell density and technology selection. Various parameters associated with the urea injection show limited influence on the increase of particulate number. In a WHTC, the specific tailpipe particulate emissions increase up to a level of 2300% compared to a reference state without urea dosing. This needs to be critically considered especially in view of stricter exhaust emission regulations scheduled post Euro VI.
Patrick Noone, Nicolas Hummel, Marcel Lehrian, Christian Beidl, Neil Kunder, Hannes Noll, Werner Hirtler, Cosimo Fiorini, Christos Dardiotis, Ansgar Wille, Kazuya Mori, Henry Jahnke, Claus Dieter Vogt, Andreas Geißelmann, Christian Tomanik
Integration of Neural Networks in GT-Suite and Coupling with an RL-Agent for Automation of Control and Regulation Tasks for a commercial H2 engine
Due to the change in mobility to lower CO2 emissions, there is a turnaround in the automotive industry. The share of classic combustion engines with petrol or diesel fuel will continue to decline. As a result, the development capacities for ICEs will also decrease. Therefore, development process becomes an even greater challenge. The IFS has been researching in the application of artificial intelligence in the development process since 2019. Various successes have already been achieved here, e.g. in virtualizing the combustion chamber or the stack of a fuel cell with the help of neural networks. Since the majority of all AI projects fail, the application of current research projects has to be carried out at an early stage. In the course of the paper, first the combustion chamber of a hydrogen engine is modelled with neural networks. In contrast to the petrol engines used in the previous papers, the combustion speed of hydrogen combustion is much higher. Despite that, very good predictions can be made with the neural networks. The connection of the networks to the 0D-/1D-simulation software, GT-Suite, is shown as an example. Here, two different possibilities are examined via the FMU interface. In the first variant, an FMU of the neural networks is generated and then integrated into the software. This makes it possible to generate a user-friendly variant that can also be sent to a calculation cluster. This was used to do a benchmark with regard to the computing speed and prediction quality. The computing time could be accelerated by a factor of 4.
In the second variant, an FMU is made from the simulation and coupled with the networks in Python. Since this also allows direct coupling with Python, an OpenAI Gym environment is set up for coupling with an RL agent. Following this, an RL agent for throttle control was trained.
Sebastian Bodza, Dominik Rether, Michael Grill, Michael Bargende, Arijeet Chakrabarty
Drop-In Renewable Gasoline Fuels for CO2 Reduction: Evaluation and Demonstration of Functional Potentials
Introducing drop-in renewable fuels into the market is the only option to effectively reduce CO2 emission of the existing vehicle fleet in near time. In this study the two EN228 compliant drop-in renewable fuels POSYN and MTO are evaluated on different gasoline engine hardware platforms. The fuel candidates are benchmarked against EN228 market fuels (RON95E10, RON98), reference fuels (EU5cert and EU6cert) and a high quality first fill fuel (ASF). First, the fuels were screened broadly by evaluation of the fuel properties including the Yield Sooting Index (YSI). Second, the fuels are evaluated in stationary engine tests and typical dynamic test cycles (WLTC, RDE) regarding emissions. Finally, the two renewable fuel candidates were analyzed in more detail via spray tests using optical measurement technologies and engine testing on combustion behavior, engine-out emissions and calibration neutrality including different conditions. The functional advantages of the fuels are highlighted. POSYN and MTO show promising results, e.g. PN emissions are significantly reduced, which is attributed to the fuel specific composition. With increasing renewable share and introducing such fuels, both well-to-wheel CO2 and criteria pollutant emissions reduction is possible within in the current vehicle fleet. Hence, lower criteria pollutant emissions and noticeable air quality improvements associated with rollout of new EU6d vehicles equipped with advanced technologies, e.g. gasoline particulate filters (GPF), can be complemented.
Hanno Krämer, Markus Send, Maik Gessner, Michael Storch, Torsten Kunz, Jan Niklas Geiler
Impact of OME-Diesel blends to a state of the art exhaust gas aftertreatment system and resulting tailpipe emissions of a multi cylinder and a single cylinder research engine
In this paper, various investigations are carried out with blends of conventional diesel fuel and the synthetic fuel oxymethylene ether (OME). OME belongs to the group of C1 oxygenates and can potentially be produced in a climate- neutral manner under certain boundary conditions. An important property is the almost soot-free combustion, which represents a great potential for emission reduction. A single cylinder research engine and a passenger car multicylinder engine are used for the presented investigations. Both engines are equipped with specific exhaust gas aftertreatment components. The aim of the investigations is to show the influence of the blending of OME on the raw emissions as well as on the efficiency of the exhaust gas after-treatment components. On the single cylinder research engine, the focus is on studying particle emissions and particle oxidation effect at stationary operating points. Whereas on the passenger car engine, low level blends are investigated in the context of stationary operating points and WLTC drives. The findings show that OME as a regenerative blend component is a promising approach to contribute to future sustainable mobility.
Alexander Mokros, Philipp Demel, Friedemar Knost, Christian Beidl
Renewable fuels from biomass and their contribution for a sustainable mobility
Moving towards a sustainable mobility is a massive challenge as this is directly connected with reducing GHG emissions in transport down to zero by 2050. Even with clear targets and measures in countries like Germany it is all about increasing. So far, reduction in only GHG emission reduction has been achieved almost completely realized by renewable fuels based on biomass. The adapted GHG mitigation quota in transport considers different compliance options including next to biofuels also electro mobility, green hydrogen and e-fuels. The current status as well as research and developments aspects of renewable fuels that can be accounted for the GHG mitigation quota are summarized. The role these fuels may play in competition with all the compliance options until 2030 is investigated in three exemplary scenarios for road transport.
Franziska Müller-Langer, Jörg Schröder, Karin Naumann
Analysis of Mixture Formation and Combustion in H2 Engines for Passenger Cars and Light Commercial Vehicles
Hydrogen is on its way to become an important energy carrier of the future. It will contribute to well-to-wheel and life cycle CO2 neutral on-road mobility solutions including EU targets for CO2 neutrality towards 2050. Following a technology neutral approach, the hydrogen engine powertrain can be an important part of potential solutions.
The paper focuses on relevant powertrain topologies for applications in light commercial vehicles (LCV) and passenger cars (PC) utilizing future hydrogen engines. The requirements and challenges on related components as well as subsystems like fuel injectors and exhaust gas treatment are discussed.
For the analysis of the H2 mixture formation, optical measurements in a pressure chamber visualizing the injected jet are used for basic understanding of the process. Further, 3D-CFD in-cylinder flow simulations are introduced for optimizing the H2 mixture preparation. The assessment of the engine efficiency based on thermodynamic loss analysis is illustrated using the cases of port fuel and direct injection.
The requirements of the exhaust gas treatment concepts for LCV/PC powertrains utilizing H2 engines are discussed, and possible configurations are shown. The results demonstrate feasibility and attractive characteristics of hydrogen engine- based powertrains for future on-road mobility.
David Lejsek, Philippe Leick, Paul Jochmann, Peter Grabner, Eberhard Schutting
Exhaust gas aftertreatment system layout for hydrogen internal combustion engines
Hydrogen internal combustion engines are already at an advanced stage of development. They can provide a sustainable CO2 free power source for vehicles in areas where fuel cell or battery electric powertrains are not a suitable option. To achieve zero impact emissions from such engines, particular attention must be paid to reducing the nitrogen oxide (NOx) emissions, which also occur in a hydrogen-fueled internal combustion engine.
In addition, substances such as ammonia (NH3) and nitrous oxide (N2O), which may result from the use of hydrogen, must be considered when developing zero impact emission concepts.
This paper demonstrates how tailored exhaust gas aftertreatment systems in combination with optimized combustion systems and engine calibration can enable a virtually emission-free propulsion system with hydrogen as fuel.
Lukas Virnich, Thomas Durand, Verena Huth, Matthias Thewes
Application of Dynamic Skip Fire for NOX and CO2 Emissions Reduction on a HD Diesel Truck and for an Off Highway Engine
Dynamic Skip Fire (DSF®) has been shown to significantly reduce CO2 on gasoline engines and has been in mass production since 2018 with more than 1.5 million vehicles produced. DSF is an advanced cylinder deactivation technology which enables any number of cylinders to be fired and dynamically decides on a cylinder event basis. Noise, vibration, and harshness (NVH) is proactively mitigated by manipulating the firing pattern and cylinder loading to avoid vehicle resonances. The technology is implemented via modification of the engine valve train and controller software where Tula’s proprietary DSF algorithms dictate each combustion event.
Diesel Dynamic Skip Fire (dDSF™) builds upon this technology and extends it to diesel engine applications. Meeting low NOX emission standards is becoming increasingly challenging, especially in lightly loaded operating conditions where maintaining ideal aftertreatment system efficiency is difficult. Most existing techniques to increase aftertreatment temperatures at low loads increase fuel consumption. Diesel applications with DSF benefit significantly from a simultaneous reduction in CO2 and NOX due to reduced heat transfer and pumping losses. The result is increased exhaust gas temperatures at low engine loads aiding emissions conversion, and a reduction in fuel spent on heating the aftertreatment system.
In this paper, the combined benefits of dDSF are demonstrated with a Cummins HD diesel engine operating in an on-highway truck and a Liebherr HD diesel engine operating in various off-highway machine applications. For the Cummins application, results are shown for steady state engine testing, transient cycle simulation, and transient vehicle tests. NVH testing and evaluation was performed at the vehicle level to characterize vehicle response and ensure acceptance of this technology. Results show a 74% reduction of NOX and a 5.0% reduction in CO2 on the Low Load Cycle (LLC) compared to the baseline engine using conventional thermal management. For the Liebherr application, simulation results show a NOX reduction of 41% and a CO2 reduction of 9.5% over a mobile crane machine cycle.
Robert Wang, Hao Chen, Vijay Srinivasan, Hans-Josef Schiffgens, Bouzid Seba, Nicolas Jansen
Variable Compression Ratio System for Next Generation Large Bore Engines - Latest Development Results
In order to meet the pollutant emission targets, set by the International Maritime Organization (IMO), an increasing number of ships using Liquefied Natural Gas (LNG) as fuel have been put into service. However, de-fossilized fuels such as green Methanol and Hydrogen are also getting more and more into focus. In this context, many shipowners are particularly interested in the dual-fuel large engine technology, which enables ships to operate with both natural gas and conventional liquid fuels. The advantages of these engines can be fully exploited by a variable compression ratio (VCR) system, which improves efficiency at part-load operation for the premixed combustion with LNG, while allowing overall efficiency to be maintained in Diesel mode, if required. Therefore, a VCR system is a technology that enables fuel flexibility in large engines with respect to low pollutant emissions and fuel economy benefits. This paper presents an innovative VCR connecting rod design for modern dual-fuel large bore engines which adapts the piston position by changing the effective connecting rod length. The VCR connecting rod was developed by the Chair of Thermodynamics of Mobile Energy Conversion Systems of the RWTH Aachen University together with FEV Europe GmbH. It features a novel functional principle inside the connecting rod’s small eye specifically tailored to the boundary conditions of large bore engines. The system includes an advanced hydraulic circuit combining the function of a hydraulic freewheel, the oil supply for piston cooling and a mechanical locking device for both compression ratios. With results of comprehensive simulation & test studies, the layout of the system is presented. The paper includes CAE and test results of the mechanical and hydraulic components. Studies on the switching process between the two compression ratios and the position of the fixed compression ratio position during engine operation are shown. This provides a deeper system understanding and identification of critical operating conditions.
Christopher Marten, Stefano Ghetti, Werner Bick, Uwe Schaffrath, Dieter van der Put
Sustainable heavy-duty transport from an energy-system perspective
The transport sector contributes significantly to global CO2 emissions. In fact, road freight accounts for 9 % of global combustion-related emissions and is expected to further grow in the coming decades.
Battery electric and hydrogen powertrains are both effective solutions to decarbonize heavy duty transport. In a recent study carried out by Shell and Hamburg University of Technology, efficiency and cost of the energy carrier supply chain were compared. The following energy-carrier-powertrain options were investigated: battery electric, gaseous hydrogen and liquid hydrogen with fuel cell and ICE as powertrain. The diesel powertrain was used as the reference case.
The paper gives a holistic overview well-to-wheel overview including the production and distribution of the energy carrier to the nozzle and the use on the truck.
The study also considers constraints from the energy system perspective, i.e. the need for seasonal energy storage and molecular energy imports into Europe. If hydrogen in the future needs to be imported into Europe at scale, is it better to reconvert into electricity and power battery electric trucks or should hydrogen be used directly in a FCEV or ICE powertrain of the truck? The answer is: both technologies will be needed in the future: battery electric trucks and hydrogen trucks. It depends on the needed share of hydrogen reconversion to power and it depends on the use case of the truck application.
Karsten Wilbrand, Jörg Adolf, Andreas Janssen, Andreas Kolbeck
Closed Carbon Cycle Mobility – Evaluation of Synthetic Fuels Based on Methanol from Renewable Sources
Regarding the reduction of CO2 emissions from the transport sector, the public debate and legislative bodies are currently focusing almost exclusively on the widespread use of battery electric vehicles (BEVs). However, it is expected that by 2030 the vast majority of the vehicle fleet stock and even by 2050, about 50% of the passenger car stock will still be powered by an internal combustion engine (ICE). Relying only on replacing the vehicle stock with BEVs will not be enough to achieve the climate targets fast enough. It is therefore an absolute must to also bring CO2-neutral fuels to the market that reduce the greenhouse gas emissions of the existing fleet with internal combustion engines. For this reason, more than 30 partners from academia and industry have joined forces across several industrial sectors in the publicly funded project “Closed Carbon Cycle Mobility” (C3-Mobility) to investigate the production and application of different synthetic fuels based on methanol from renewable sources. C3-Mobility has been funded by the German Federal Ministry of Economic Affairs and Climate Action under the grant number 19I18006.
Benedikt Heuser, Johanna Otting, Thorsten Schnorbus, Martin Müther
Mobility of the Future – Mood Among Mobile Citizens
With the help of surveys conducted in 2016, 2019 and 2021, ÖAMTC surveyed the mood of mobile citizens in relation to e-mobility and to vehicle assistance and equipment systems. Some of the results were surprising.
With regard to e-mobility, there were increases in the level of information and personal charging options, while range anxiety decreased.
When it comes to environmental friendliness, electric vehicles are no longer rated as highly as they were in 2016. The view that electric vehicles are harmful to the environment is becoming more dominant and fire risks are viewed as a greater hazard. Hydrogen-based power trains are seen as the source of the future for powering passenger cars after 2050.
Combustion engines will remain the most common power source for new vehicles purchased in the next five years. Costs and monetary aspects (tax benefits, bonuses, free parking, etc.) are and will remain the key factor when a new vehicle is purchased, with half of respondents stating that they would buy a vehicle on the new car market, the other half on the used car market.
The attitude of many respondents to assistance and entertainment systems paints an ambivalent picture. The fact that assistance systems increase safety is undisputed, but they can also be annoying and even cause stress for 6%. Other annoyances reported by respondents included malfunctions and feeling overwhelmed by these systems. Nevertheless, the equipment provided plays a major role when a new vehicle is purchased.
Thomas Hametner, Andrej Prosenc, Jürgen Blassnegger
Renewable and eFuels take us closer to the climate goals
Climate change is the most pressing challenge we face today. The urgency to address transport emissions must drive a fundamental change in the way we power mobility. Business as usual is simply not an option.
Over the past 200 years, fossil fuels have come to power the vast majority of transport on land, at sea and in the air. We cannot continue depleting fossil resources and releasing its sequestrated carbon into the atmosphere. The era of fossil fuels must end.
We need to drive improved sustainability in the transport sector by replacing all fossil fuels with climate-friendlier alternatives. This means replacing liquid fossil fuels as well as all fossil fuels used to generate electricity or produce hydrogen. The Well-to-Wheels approach helps us take all the relevant carbon emissions into account and helps us make more sustainable choices. We need to base the future of the transport sector on renewables; we need renewable energy to produce electricity, hydrogen and e-fuels, as well as, renewable raw materials to produce liquid or gaseous fuels.
In November 2021the EU Innovation Fund gave a positive grant decision of EUR 88 million funding to Neste’s green hydrogen and CO2 capture & storage project, which aims to quickly and efficiently reduce greenhouse gas emissions at the Porvoo refinery in Finland. The project introduces carbon capture and storage (CCS) and electrolysis solutions that allow decarbonisation of production at the refinery. The project is currently in the feasibility phase.
With the availability of green hydrogen and CO2 there is also possibilities to start producing power-to-liquids like eFuels for different applications. Neste also explores this technologies thru partnerships and joint research projects to evaluate different technology paths.
M. Hultman, T. Sarjovaara
xHEV-concept for achieving the 2030 CO2 emission targets
Public perception of the automobile is currently very focused on environmentally sustainable drive trains. Legislation for Europe envisages a 37.5 % reduction in CO2 emissions for passenger car fleets brought to market by 2030, with values towards 55-75 % under discussion. To comply with these ambitious targets, most OEMs anticipate a significant share of vehicles with electric hybridized powertrains (xHEVs) and battery electric vehicles (BEVs). In this study, vehicles belonging to different segments are defined to create a “representative fleet” for a virtual OEM in 2030. Taking into account the diverse use cases (e. g. predominantly city driving vs. long distance commuting) and customer preferences (e. g. low-cost vs. high performance requirements), different powertrain architectures are defined for each vehicle segment. It is shown that a CO2- reduction of 55 % can be achieved in 2030 even with a still rather low BEV share of 15 %, with a chance of achieving 75 % reduction with a BEV share of slightly more than 50 %. In a second step, the real-driving behavior incl. battery charging strategy of the end-user as well as the battery sizing for plug-in-hybrids (PHEVs) are considered. The Hybrid BEV concept is presented as an approach for the D/Esegment to reduce the number of platforms for 2030 and beyond.
Matthias Thewes, Tolga Uhlmann, Christian Sahr, Norbert Alt, Dominik Lückmann, Andreas Balazs, Tobias Vosshall, Matthias Uebbing, Christian Kürten, Peter Zwar, Andreas Müller
Thermal management of e-drivetrains through new cooling fluids
Many governments mandate rapid electrification of cars to limit carbon dioxide emissions from the private transport sector. The performance requirements for batteries are increasing due to high currents arising from ultra-fast charging, dynamic driving, increasing energy density and more demanding system safety requirements. Conventional indirect battery cooling systems with glycol/water can not sufficiently control the battery temperatures which then in turn can lead to reduced battery life. It has been demonstrated that immersive battery design with new dielectric cooling fluids can significantly improve thermal management performance of batteries under fast charging conditions allowing high charging and discharging rates. Safety performance of immersive battery systems has been demonstrated with different cell form factors by successfully passing the abuse test requirements. Material compatibility of the new cooling fluids with typical construction materials and material impact on dielectric fluid properties have been evaluated. Accelerated aging tests demonstrated life-time performance of battery systems with the new cooling fluid types.
Volker Null
Spark Ignition - Searching for the Optimal Spark Profile
The impact of different spark designs on the ignition and combustion stability is studied using a 13-liter CNG fueled heavy duty spark ignited engine to search for the “optimal” spark design. Experimental results show that robust ignition can be achieved using a significantly shorter spark duration and lower energy than expected. A capacitive discharge ignition (CDI) system enabled to separately control the available spark voltage, current and duration (FlexiSpark® CDI) was compared to a standard CDI system without spark control and an inductive discharge (IDI) ignition system. Typically, a robust ignition can be provided using only 5% of the spark duration and 17% of the spark energy compared to that required by an IDI system to accomplish an equivalent ignition and combustion stability. By applying control of the spark, a robust ignition can be provided which is optimized for the fuel, the engine design, the engine operating condition, and the condition of the spark plugs. This offers a potential to significantly reduce the spark-plug wear and the total cost of ownership without compromising engine performance. The results are especially interesting in the view of hydrogen fueled SI-ICE, where the required available spark voltage is high, but the required spark energy is low. It is desirable to use a spark design with just enough voltage and power to initiate a sustainable combustion, but with minimal energy not to excessively wear and heat the spark plug electrodes to avoid preignition.
Jakob Ängeby, A. Saha, O. Björnsson, M. Lundgren
Direct Air Capture (DAC): Challenges and Opportunities to Meet Climate Targets
There is increasing emphasis on removal of carbon dioxide from the atmosphere as a key strategy for meeting climate change mitigation goals. The two leading approaches are direct air capture and bioenergy with carbon capture. Both can involve either an offset of fossil fuel use or carbon dioxide sequestration, the latter providing a carbon negative result. In this brief review, we discuss the pros and cons of these two systems with emphasis on direct air capture and the approaches employed by the three companies with the most advanced commercial aspirations.
Hans Kistenmacher, Ron Chance, Peter Eisenberger
Measures to increase the CO2 reduction potential of renewable fuels in the period up to 2030
Man-made climate change will have significant consequences. In order to develop solutions for the task of limiting CO2 emissions all stakeholders in road transport have to rethink their roles and responsibilities. The Volkswagen AG and the Robert Bosch GmbH have already supported the market introduction of drop-in climate fuels to address the need of existing vehicle fleets but see additional efforts that require close collaboration of all stakeholders. To support climate targets set for 2030 as per the European Green Deal in a sustainable way many perspectives need to be considered. The paper aims to stimulate a discussion on the proposed directions of such collaboration.
Thomas Garbe, Bjoern Noack
The off-highway sector in the field of tension of future power train concepts - Which chances has the internal combustion engine (ICE) in this industry?
Combustion engine with diesel fuel are currently the most convenient power train for Off-Road application thanks to its higher energy density and shorter refueling time. However, the increase in global warming leads to a defined limit of the CO2 budget until 2050 which forces several authorities to establish strict regulations on pollutant and CO2 emissions. These stringent CO2 limitations are challenging for manufacturers, and driving them to develop new technologies and concepts (mainly zero emission power trains) to decarbonize their fleet. The current solution and trends for zero emission technologies are based on Tank-to-wheel approach, which considers only CO2 emission generated by machine operation. A more global approach for evaluation of CO2 emission in the whole chain such as “Well-to-wheel” is more suitable in order to respect the limited CO2 budget by 2050. This paper reviews the current investigations regarding ZE powertrain technologies in Off-Road sector, analyzing of the different type of power train in terms of power and energy density. After that, the duty condition in the Off-Road sectors has been explained, followed by a review of the application of new technologies such as fuel cell, battery electric vehicle and combustion engine in Off-Road sector.
Ulrich Weiss
Renewable Engine Oils Test
Evaluation of the Evolve Lubricants, Inc. (“Evolve Lubricants”) renewable non-petroleum crankcase finished lubricant with respect to wear under severe operating conditions using the Porsche MA203 3.0-liter turbo charged engine and gasoline fuel POSK E25. The test was performed on behalf of Porsche AG (“Porsche”) by APL Automobil-Pruftechnik Landau GmbH, Landau, Germany during July 2021. The unique test is designed to provide valuable data not highlighted in current ACEA tests. This includes oil ageing before wear testing, simulated high performance and racetrack conditions, high piston ring grove temperatures, worst case fuel scenarios addressing hybrid use cases with significant oil dilution and no oil top up or revitalization during the test. The entirety of the testing sequence and total test length is proprietary to Porsche. The length and duration of the test exceeded one hundred hours.
Rick Lee
Internationaler Motorenkongress 2022
herausgegeben von
Alexander Heintzel
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