Internationaler Motorenkongress 2019

Frontmatter

FVV fuel study: Options for the defossilization of the transportation sector (100 % scenarios)

Zusammenfassung

The European Union overall greenhouse gas (GHG) emission target is an 80 % – 95 % reduction from the GHG emissions emitted in 1990, the German target of 95 % reduction is even tougher.

Ulrich Kramer, Stephan Stollenwerk, Felix Ortloff, Xavier Sava, Andreas Janssen, Steffen Eppler, Harry Schüle, Arndt Döhler, Reinhard Otten, Martin Lohrmann, Lars Menger, Sebastian Barth, Werner Kübler, Ralf Thee

Is car driving good or evil? The economic vs. the ideological view

Zusammenfassung

While car driving was once a synonym for liberty and welfare, not at least in the former Eastern German Democratic Republic, this has dramatically changed in recent years. We do no longer want to see cars in our cities, we accuse them for polluting the air and causing too much noise, we blame them for thousands of killed and injured people in accidents, and we try to bully them where-ever we can. The Diesel-bans in German cities are only the most recent climax in this change of thinking.

Ulrich van Suntum

RDE cycle generation – a statistical approach to cut down testing effort and provide a secure base to approve RDE legislation compliance

Zusammenfassung

The progression of emission legislations in Europe and China has increased the engagement of the automotive industry in the development of improved exhaust gas aftertreatment systems. The fulfillment of PN, NO_x and expected CO limits in real world driving scenarios has led to the introduction of gasoline particulate filters, and moreover has significantly increased the work load for calibration engineers and on calibration testing resources. Many OEMs are in extreme task force modes to hold planned SOPs, and some were even forced to reduce their product portfolio. This is due to the large testing matrix, required to cover all possible Real Driving Emissions (RDE)-driving scenarios. This paper presents an RDE-cycle-generator to tackle the huge RDE work load. This RDE-cycle-generator is based on FEV’s large real driving emission measurement data base. It enables reproducibility and significantly cuts down testing effort, while representing a secure base to approve RDE legislation compliance.

Johannes Claßen, Stefan Sterlepper, Frank Dorscheidt, Michael Görgen, Johannes Scharf, Martin Nijs, Norbert Alt, Andreas Balazs, Marius Böhmer, Matthieu Doucet, Sascha Krysmon, Christian Boßer

Consistent powertrain behavior – the key to achieve customer acceptance?

Zusammenfassung

Within todays powertrain development, the reduction of green house gas emission is of high priority. On October 9th 2018 the Environmental Ministers of the European Member States published their proposal for setting efficiency standards for new passenger cars for the timeframe 2021-2030 amending European Commission’s proposal from November 2016. The resolution foresees a reduction of CO₂ emission for new passenger cars by 15% until 2025 and 35% until 2030, based on the average fleet target value of the year 2021 [1]. To achieve these targets, an improvement of the total powertrain system efficiency is required.

Sebastian Barth, Derya Karabulut, Michael Fischer

The ICE in the electrified powertrain – modular approach within a common platform between cost and CO2 optimization

Abstract

The electrification of the powertrain is a prerequisite to meet future fuel consumption limits, while the internal combustion engine (ICE) will remain a key element of most production volume relevant powertrain concepts.

The high volume applications will be covered by electrified powertrains. The range will include parallel hybrids, 48V- or High voltage Mild- or Full hybrids, up to Serial hybrids.

In the first configurations the ICE is the main propulsion, requiring the whole engine speed and load range including the transient operation.

The competition of different technologies and variabilities, from variable compression ratio (VCR) to variable valve lift (VVL), advanced boosting technologies, high pressure injection at the gasoline engine, as well as add on measures such as water injection require a modular common engine family architecture with common parts and common machining and assembly concepts, as well as the feasibility to integrate different technology packages.

At serial hybrid applications the vehicle is generally electrically driven and the ICE provides power to drive the generator, either exclusively or supporting a plug-in battery charging concept. As the ICE is not mechanically coupled to the drive train, a reduction of the operation range to preferred load and speed ranges with high efficiency is feasible and transient as well as idle operation is irrelevant. Thus a partial simplification of the ICE is achievable.

The paper shows the chances of a modular technology approach, with focus on a balanced overall complexity of the powertrain with increasing electrical power in regard of Cost and CO₂-reduction.

Wolfgang Schöffmann, Helfried Sorger, Alois Fürhapter, Paul Kapus, Gerald Teuschl, Christoph Sams

Electric turbo, a key technology to achieve Eu7 hybridized powertrain (lambda 1, performance and energy efficiency)

Zusammenfassung

Global Light Vehicle production is set to rise towards 110M units p.a by the year 2025. Approximately 60% of those are expected to contain Turbocharged Powertrains. Hybridization will rise rapidly as it is the most cost effective route to lower emission and fleet CO2 in a period where cost, infrastructure and customer acceptance will still be significant ‘barriers to entry’ for fully electrified Vehicles such as BEV and FCEV.

N. Bontemps, A. Bas, M. Ladonnet, D. Zecchetti, S. Heintz, Peter Davies

Water injection for gasoline engines – potentials and challenges

Zusammenfassung

Specific engine power has significantly increased within the last decades as can be seen in Figure 1. For mass production powertrains a power density of more than 85 kW/l will be required in the future. On the other side the upper limit of stoichiometric operation has almost kept constant over the last years.

Ingo Hermann, Claus Glahn, Martin Paroll, Werner Gumprich

Combined application of 3D-CFD and high-speed video endoscopy on a turbocharged GDI engine

Zusammenfassung

The internal combustion engine will remain the dominant drive for individual mobility in the future. Gasoline direct injection (GDI) in combination with turbocharging plays a key role for a further reduction of CO2 emission. A major challenge for these kinds of engines is the reduction of particle number emissions (PN), whereby the injection system is the key component.

Markus Bertsch, Michael Lippisch, Wolfram Wiese, Erik Schünemann

Optimizing gasoline particulate filter technologies to improve filtration performance

Zusammenfassung

Gasoline Particulate Filters (GPF) are one of the primary technologies which are able to effectively reduce particulate number (PN) emissions from Gasoline Direct Injection (GDI) vehicles. Due to increasingly stringent global emission requirements as well as the implementation of Real Driving Emission (RDE) testing conditions, it is critical to continuously develop and improve GPF performance.

Previous investigations have shown that GPF PN filtration performance improves over the lifetime of the product, primarily as a result of Ash and Soot accumulation on the walls of the inlet channels in the filter. Additionally, it was identified that PN emissions generated during the cold start phase of a test cycle represent the primary portion of the total particles emitted during the test. Therefore further optimizations in particle number filtration performance should be concentrated at improving the initial filtration, subsequently defined as the “fresh” filtration performance, of the GPF material.

This paper investigates the next development steps and iterations in GPF technologies which will result in improved fresh filtration performance while maintaining acceptable pressure drop levels. Potential development materials will be compared by characterizing their performance through vehicle testing under laboratory conditions by using a 3-line particle number measurement setup (direct upstream GPF, direct downstream GPF, CVS tailpipe). Moreover, the influence of particle size on the filtration efficiency will be investigated by measuring particle size distributions in the range from 5nm up to 1000nm with and without a GPF installed.

David Waters, H. Jahnke, D. Thier, Y. Ito, F. Gaermer dit Richter, F. Striebel, C. D. Vogt, F. Yoshioka, K. Kato, T. Aoki, M. Yamashita, M. Makino

How to address durability-related challenges in commercial vehicle gas engines

Zusammenfassung

Engine developers for heavy duty commercial vehicles face major challenges in the coming years. On the one hand, more stringent pollutant levels are being discussed and partly already implemented. On the other hand, limitations on greenhouse gas emissions will require further improvements in fuel economy.

Johannes Gell, Johannes Andersen, Anton Arnberger, Gernot Hasenbichler

Impacts of powertrain hybridization on engine exhaust behavior of heavy‑duty vehicles with electrified trailers

Zusammenfassung

With regard to the Paris climate contract, the European Commission (EC) worked out a legislative proposal for CO₂ emission standards for heavy duty vehicles, which was presented in 2018 [6, 7]. The legislative proposal provides a reduction of tank-to-wheel CO₂ emission by 15 % in 2025 and by 30 % in 2030, both compared to a still to determine average value of 2019. Compared to today´s typical 40t-vehicle fuel consumption, this equals a reduction from 33 L/100km to about 23 L/100km in 2030 (Figure 1).

Mikula Thiem, Nicolas Hummel, Christian Beidl

Dedicated diesel range extender engine for medium-duty delivery trucks

Zusammenfassung

To address the global climate change concerns, challenging goals for the reduction of anthropogenic greenhouse gas emissions have been set as per the 2015 Paris Agreement of the United Nations Framework Convention on Climate Change [1.1]. One major contribution towards achieving this goal, is expected to come from fuel economy improvements in the field of transportation. In addition to the already established legislative regulations for the fleet CO2 emissions/fuel consumption for Light- and Heavy- Duty vehicles in the United States, China and Japan [1.2, 1.3, 1.4], the European Commission presented a two-stage legislative proposal setting CO2 standards for Heavy- Duty truck applications in May 2018 [1.5].

Markus Ehrly, Joschka Schaub, Korbinian Vogt, Farouk Odeim, Bernd Lindemann, Stefan Wedowski, Matthias Kötter

Modular HJS heavy-duty exhaust gas aftertreatment system with independent thermal management for high NOX conversion especially in urban operation

Zusammenfassung

With the European Directive 2008/50 EC on Ambient Air Quality [1], the European Commission is pursuing the goal of ensuring that the annual average ambient air quality limit of 40 μg/m3 for NO2, which has been in force since 2010, is ensured. Compliance with this directive is a major challenge for many municipalities and federal states.

Especially in urban areas, NO2 limit values are often exceeded. Transient low-load operation with low exhaust temperatures and sometimes high NOX raw emissions during the acceleration phases also pose special challenges for the complex exhaust aftertreatment systems of buses and commercial vehicles. With regards to the problem of Real Driving Emissions (RDE) in the urban environment and in light of the expected future exhaust emission legislation, HJS has further developed the well-known SCRT technology and added important technology components.

In addition to highly efficient catalytic converters and optimized NH3 mixture preparation, the focus was placed on autonomous thermal management technologies and corresponding control algorithms in order to achieve very high NOX conversion rates even in demanding urban operation. The first application of this modular HJS heavy duty exhaust aftertreatment platform is in city buses.

Diesel particulate filters are well established to reduce particulate emissions from diesel engines and are being used in most new applications already.

The guidelines for retrofitting diesel buses as part of the “Sofortprogramm Saubere Luft 2017 – 2020” have defined emission limits and testing boundary conditions which even go beyond the IUC regulations for Euro VI buses, especially in inner-city operation.

In order to meet the emission requirements of this directive in real city bus operation, a thermal management is required in addition to an optimised EURO VI exhaust gas aftertreatment with DOC, DPF and SCR in order to operate the SCR system in an efficiency-optimised temperature window even at the lowest speed profiles.

The modular heavy duty exhaust aftertreatment system with independent thermal management presented in this paper aims to significantly increase the efficiency of the SCR system in transient inner-city operation. The exhaust gas temperature in the low load range is raised by up to 50 °C for this purpose. Central elements for this are a quick, electrically controlled and operated exhaust flap along with an electrically heated diesel oxidation catalyst.

With the aid of the exhaust flap, the exhaust back pressure is increased in certain driving situations. The electrically heated catalytic converter arranged in front of the particulate filter increases the exhaust gas temperature and increases the engine load via the additional load on the alternator.

The HJS ACU control unit processes the measured values such as NOx flux, temperatures, pressures, exhaust gas mass flow, status of the electrical system, etc. and controls the actuators in such a way that the best possible NOX reduction is achieved with minimum fuel consumption penalty. The system is also fully diagnosable.

The HJS system contributes immediately to the reduction of NOx emissions and thus to improved air quality in urban areas. The modular concept and the smart CAN bus and sensor-based control also qualifies the HJS system for other commercial vehicle applications beyond city bus applications and EURO VI legislation. For the first time, engine heating measures can be enhanced by engine operating point independent thermal management measures to help reliably meet future RDE-focused legislation in critical city operation.

In the following, the performance of the system will be demonstrated as an example for retrofitting a city bus application.

Christoph Menne, Klaus Schrewe, Bernd Maurer, Jens Schlencker

Assessment of factors influencing the wall heat transfer with regard to increasing efficiency and compliance with future CO2 limits for commercial vehicles

Zusammenfassung

More than 125 years ago, Rudolf Christian Karl Diesel succeeded in putting the first 4-stroke heat engine, later called Diesel engine after its inventor, in operation [1]. The reached increase of efficiency, by three or four times compared with the efficiency of steam engines at this time, and the resulting advantage of the Diesel engine has not lost any actuality in today’s engine development ever since. Right now, confronted with strictly increasing emission control laws, while there’s a change to a multi-drive-technology path, the efficiency increase of the Diesel engine is more important than ever. Moreover the buyers demand is still a low total cost of ownership, which is depending mainly on the engines fuel efficiency.

Christian Hennes, J. Lehmann, P. Kožuch, T. Koch

Influence of engine cooling concepts on fuel economy and performance – results of the simulative investigations and test bench measurements

Zusammenfassung

The primary function of an engine cooling system is to transfer heat to the environment – defined as a heat sink, which is generated by combustion as well as in the charge air path, during compression of air. The thermal load of the combustion unit is dependent on the turbocharging concept (e.g. one- or two stage), type of charge air cooling (direct, indirect), concept of exhaust after treatment (SCR, EGR) and the overall thermodynamic efficiency of the engine. The thermohydraulic and geometrical layout of the cooling system makes it possible to meet the condition of all criteria, within the defined limits.

Alexander Schydlo, Robert Martens, Dominik Renner, Thomas Malischewski

Hydrogen as the basis for mobility with a low carbon footprint: from a fundamental, technological, economic and ecological perspective

Zusammenfassung

In nature, hydrogen (H) occurs in large quantities only in combination with either oxygen (O), in the form of water (H₂O), or carbon (C) in the form of natural gas, which mainly consists of methane (CH₄), as well as in the form of crude oil (CH₂), coal (CH) or biomass (CHOH).

Otto Machhammer, Hans-Jürgen Maaß

Normung von Kraftstoffen und die Bedeutung für die Realisierbarkeit neuer Kraftstofflösungen

Zusammenfassung

Was ist Normung? Wie für fast alles gibt es auch hier verschiedene Definitionen. Man sollte annehmen, dass die Normung selbst es am besten weiß: die ISO 45020:2007 beschreibt Normung als die Formulierung, Herausgabe und Anwendung von Regeln, Leitlinien oder Merkmalen durch eine anerkannte Organisation und deren Normengremien. Sie sollen auf den gesicherten Ergebnissen von Wissenschaft, Technik und Erfahrung basieren und auf die Förderung optimaler Vorteile für die Gesellschaft abzielen. Die Festlegungen werden mit Konsens erstellt und von einer anerkannten Institution angenommen.

Jürgen Fischer

System approach for future diesel blends with sustainable fuels

Zusammenfassung

In the Paris Climate Agreement of 2015, the not-to-exceed limit of 2 °C global warming until 2050 was defined and in Katowice, 2018, measures were agreed how to control the activities of participating nations. To meet the mentioned target of global warming limitation, worldwide CO₂ emitting processes must be improved in all industry and life sectors. Hence, transport industry and therefore propulsion systems of passenger cars and trucks must reduce their CO₂ emissions as well. The European Union just recently defined the CO₂ reduction targets to 15% and 37.5% for 2025 and 2030, respectively, for passenger cars (based on the 2021 CO₂ emissions value for 100 km driving distance).

Beside full electrical and hybrid vehicles, the application of sustainable fuels in combustion engines is supposed to become an important brick for the required CO₂ reduction. These fuels can be based on bio sources or synthetically produced. CO₂ must be the carbon source for any of these sustainable fuels. This is taken either from bio sources or from industry gases or directly captured from atmosphere. Hence, during fuel production process CO₂ is captured (Well-to-Tank) and during the usage in any combustion process and therefore also for usage in propulsion systems (Tank-to-Wheel) this CO₂ is released again to the atmosphere. Overall, the CO₂ is moved in closed loop without any climate impact. If H₂ is used in the production process of the fuel, it has to be produced from green electricity, the same is valid for any energy required in the production process.

Continental, as an FIE system supplier, evaluated the bio fuel R33 and the synthetical fuel OME15% with respect to its fossil partner (B7 reference diesel fuel) on a diesel car. The fuels were tested on the Super Clean Electrified Diesel Vehicle (SCED) developed at Continental under WLTC and RDE driving conditions. The SCED (C-segment vehicle) shows very low NO_x emissions below 25 mg/km in WLTC and below 35 mg/km under all ambient temperature and driving conditions, due to the integration of Continental components (48 V Belt-starter-generator, EMICAT^®, FIE System) and sophisticated engine and after treatment system management strategies, all developed by Continental.

G. Rösel, Giovanni Avolio, J. Grimm, O. Kastner, T. Swigon, M. Weisse

Operation of a diesel engine with intake manifold alcohol injection

Zusammenfassung

The transport sector is a major contributor to the greenhouse gas emissions in the European Union with a share of about 24 % in 2016 [1]. Reducing CO₂ from traffic is crucial for achieving the desired climate stabilizing objectives and lowering the dependence on fossil fuels. The efforts on this field should be supported by rational as well as technically and economically feasible sustainable solutions. Increasing the usage of biofuels is one of these solutions [2].

Aleksandar Damyanov, P. Hofmann

Flex-fuel capability via advanced digital combustion rate shaping and airpath control

Zusammenfassung

The worldwide four warmest years (2015-2018) since weather records began and a new peak CO₂ concentration in the atmosphere [2] highlight the urgency of reducing the anthropogenic CO₂ emissions. Only with the expansion of power generation from regenerative energy sources, a drastic reduction of CO₂ emissions is possible. Due to the fluctuating nature of these sources, new challenges arise. The storage of larger amounts of energy needs to be realized by gaseous or liquid energy carriers [6].

Daniel Neumann, Paul Muthyala, Christian Frenken, Joschka Schaub, Christian Jörg, Matthias Kötter

Combustion process optimization for oxymethylene ether fuels in a heavy‑duty application

Zusammenfassung

Oxymethylene ethers (OME) are synthetic fuels based on C1 chemistry, which can be produced from sustainable feedstocks like waste CO₂ and hydrogen out of electrolysis [10]. The constitutional formula of OME_n is CH₃-O-(CH₂-O)_n-CH₃ while the number of oxymethylene groups n determines the chain-length of the molecule. OME_n with 0 ≤ n ≤ 6 are suitable as diesel fuels because of their good ignitability.

Kai Gaukel, Patrick Dworschak, Dominik Pélerin, Martin Härtl, Georg Wachtmeister

Analysis of two engine configurations using OME as a potential CO2-neutral and low emission diesel substitute

Zusammenfassung

The increasingly stringent CO₂ limits of the European Union require a total elimination of greenhouse gas emissions for the transport sector by the year 2050. In addition, pollutant emissions must be further reduced in order to improve air quality, especially in urban areas. The necessary technologies for the reduction of pollutant emissions are state of the art, but must be spread over time by a renewal of the existing fleet in the market and also be further developed.

Markus Münz, Alexander Mokros, Christian Beidl

The new highly efficient hydrogen internal combustion engine as ideal powertrain for the heavy-duty sector

Zusammenfassung

Obvious changes in the world‘s climate make action necessary. Burning of fossil fuels in combustion engines not only results in CO2 emissions but also NOx and other pollutants harmful to all living beings. Today’s transport sector, including air, rail, marine, road transport and traffic, is responsible for almost a fifth of the world’s CO2 emissions.

Thomas Korn

Transport policy and climate change: and never the twain shall meet?

Zusammenfassung

In today’s political discussions, the challenge to decarbonise transport is moving center stage. A stringent regulatory framework is being put in place by the EU, taking 2030 into focus. Studies show that to follow an optimal path towards de-carbonisation of the transport sector, priority should be given to a wide array of technology measures with a focus on achieving the 2050 climate goals.

Kurt-Christian Scheel