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2022 | Buch

# 22. Internationales Stuttgarter Symposium

## Automobil- und Motorentechnik

herausgegeben von: Prof. Dr. Michael Bargende, Prof. Dr. Hans-Christian Reuss, Prof. Dr. Andreas Wagner

Buchreihe: Proceedings

Enthalten in:

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SUCHEN

### Über dieses Buch

Band I
In einer sich rasant verändernden Welt sieht sich die Automobilindustrie fast täglichmit neuen Herausforderungen konfrontiert: Der problematischer werdende Rufdes Dieselmotors, verunsicherte Verbraucher durch die in der Berichterstattungvermischte Thematik der Stickoxid- und Feinstaubemissionen, zunehmendeKonkurrenz bei Elektroantrieben durch neue Wettbewerber, die immer schwierigerwerdende öffentlichkeitswirksame Darstellung, dass ein großer Unterschiedzwischen Prototypen, Kleinserien und einer wirklichen Großserienproduktion besteht.Dazu kommen noch die Fragen, wann die mit viel finanziellem Einsatz entwickeltenalternativen Antriebsformen tatsächlich einen Return of Invest erbringen, wer dienotwendige Ladeinfrastruktur für eine Massenmarkttauglichkeit der Elektromobilitätbauen und finanzieren wird und wie sich das alles auf die Arbeitsplätzeauswirken wird.Für die Automobilindustrie ist es jetzt wichtiger denn je, sich den Herausforderungenaktiv zu stellen und innovative Lösungen unter Beibehaltung des hohenQualitätsanspruchs der OEMs in Serie zu bringen. Die Hauptthemen sind hierbei,die Elektromobilität mit höheren Energiedichten und niedrigeren Kosten der Batterienvoranzutreiben und eine wirklich ausreichende standardisierte und zukunftssichereLadeinfrastruktur darzustellen, aber auch den Entwicklungspfad zum schadstofffreienund CO2-neutralen Verbrennungsmotor konsequent weiter zu gehen. Auch dasautomatisierte Fahren kann hier hilfreich sein, weil das Fahrzeugverhalten dann –im wahrsten Sinne des Wortes - kalkulierbarer wird.Dabei ist es für die etablierten Automobilhersteller strukturell nicht immer einfach,mit der rasanten Veränderungsgeschwindigkeit mitzuhalten. Hier haben Start-upseinen großen Vorteil: Ihre Organisationsstruktur erlaubt es, frische, unkonventionelleIdeen zügig umzusetzen und sehr flexibel zu reagieren. Schon heute werdenStart-ups gezielt gefördert, um neue Lösungen im Bereich von Komfort, Sicherheit,Effizienz und neuen Kundenschnittstellen zu finden. Neue Lösungsansätze,gepaart mit Investitionskraft und Erfahrungen, bieten neue Chancen auf dem Weg derElektromobilität, der Zukunft des Verbrennungsmotors und ganz allgemein für dasAuto der Zukunft.

### Inhaltsverzeichnis

#### EU7 Emission Limits

##### Electrically Heated Catalyst for Emissions Reduction for Euro7

For Euro7 real driving cycles require an increase in exhaust gas temperature at cold start. This paper presents results on the emissions reduction effects of using an electric heating catalyst. Different heating strategies for diesel and gasoline engines are discussed. The application in diesel engines requires a high heat input into the exhaust gas already at very low mass flows in order to heat up also the downstream components of the SCR system quickly. Measurements and simulations are used to show how the heat input is influenced by the geometry and the heat transfer surface of the heating element and how this is affected under different operating conditions. Measurements on the engine test bench show the potential for emission reduction. In addition, it is shown that a catalytic coating of the heating element results in a further increased emission reduction. Particular emphasis is placed on robustness in operation. The presented Lamella Heater is tolerant to fuel and AdBlue and due to its fully insulated design insensitive to condensate and particles.

Gerd Gaiser, Tobias Lehr, Volker Brichzin
##### EU 7: A First Assessment

The next European emission regulation, EU 7/VII for Light- and Heavy-Duty Vehicles is under discussion since end of 2018. First proposals were published in the first half of 2021.Within the scope of the EU 7 regulation emission limits of the on-road emissions are to be further reduced and additional components are to be regulated, nitrous oxide, methane, ammonia, and formaldehyde for instance. By the end of 2021 an official draft regulation is expected to be published by the European commission.Despite the transition in automobile powertrains, diesel will remain important in the powertrain mix as highly efficient powertrain with a high milage range, especially for heavy duty and light commercial vehicles.Powertrain Solutions as business unit of the Robert Bosch GmbH has been conducting comprehensive studies for diesel and gasoline powertrains by means of demonstrator projects for many years. Technical requirements are derived from these and customers receive the best possible support in complying with future emission limits.In this paper a first assessment of the EU 7 proposal for the diesel PC segment is presented. Furthermore, the assessment is extended to the light commercial vehicles through a hardware-in-the-loop approach.The focus is on nitrogen oxide emissions, which have been the primary focus over the past few years and on emission components that are new in the upcoming EU 7 regulation, such as nitrous oxide.At the time when this report was written, the EU Commission had not yet published its official EU 7 draft. For this reason, this assessment is based on the proposals of the CLOVE consortium, the scientific advisory group of the EU Commission, that were published in April 2021.

Stefan Bareiss, Michael Krüger, Andreas Kufferath, Dirk Naber, Herbert Schumacher, Marcel Wüst
##### Euro 7 Light Duty SCR System Solution with Software-Extraction of the Ammonia-Signal from NOx-Sensors

Two-stage SCR systems with double dosing are now state of the art for passenger cars and light commercial vehicles and thus the starting point for meeting future Euro7 requirements. Even lower emission limits, the regulation of further exhaust gas components such as NH3 and N2O, the extension of the RDE boundary conditions and On Board Monitoring will be core requirements for the SCR system. Therefore, hardware and software of the SCR system will have to be further developed or newly developed accordingly. For the AdBlue dosing system, this results in new requirements for monitoring capability, dosing quantity accuracy and fast system readiness, which have been implemented with the new Denox5.3 generation. The central Euro 7 requirements for the NOx sensor are a fast signal readiness from engine start as well as an even further increased accuracy, which have been incorporated into the development of the new sensor generation EGS-NX3. In order to achieve robustly high efficiencies, closed-loop control is required that takes into account the system architecture of the two-stage SCR system. For this purpose, it is important to know the NH3 levels in both catalysts as precisely as possible. However, the NOx sensor at the position between the catalysts can only measure the sum of NOx and NH3. With sophisticated software procedures, it is nevertheless possible to infer the respective NOx or NH3 signal components and thus increase system performance without additional sensor costs.

Dirk Samuelsen, David Sammet, Thomas Wahl, Erik Weingarten

#### Electric Powertrains

##### Optimized Drive Systems for Electric All-Wheel Drive Vehicles

In this paper, three different possibilities of torque distribution as well as three different kinds of electric motor configurations for an electric all-wheel drive vehicle are simulated. The used vehicle for the observation has two electric drive systems, each integrated into an E-Axle. Each E-Axle has either an induction or a permanent magnet synchronous motor as well as a two-speed-gearbox and a separating clutch. The three different torque distributions include a 50/50-torque split between front- and rear-axle, a front-axle-drive with a rear-axle-drive option for high loads and an optimal torque distribution with consumption minimization strategy. The electric drives vary first by using two E-Axles with induction motors. Second, a variation with a permanent magnet synchronous motor on the front-axle and an induction motor on the rear-axle. Third, a configuration with both motors being permanent magnet synchronous motors. Each configuration is validated in three different load cases by varying the drive cycles as well as adding a 2.0 t trailer to the SUV base vehicle. In conclusion, the simulation results show the different effects of operational strategy and the configuration of the motors on the overall electric energy consumption of the all-wheel drive vehicle.

Tobias Stoll, Michael Bargende, Hans-Jürgen Berner
##### Model-Based Design and Evaluation of Future Fail-Operational Electric Drivetrains

In highly and fully automated vehicles, a driver is not required to permanently supervise the driving task. This leads to new requirements on fail-operational system behavior with the goal to reach a safe state in case of a fault. With fail-operability of the propulsion system, a vehicle can be stopped outside of active traffic, increasing the safety of passengers. Thus, it is assumed as a requirement for future electric powertrains. Fail-operability is generally achieved with redundancy at different architecture levels to ensure a minimum required level of functionality in case of a fault. This also leads to additional degrees of freedom for enhanced control in fault-free operation. In this work, a model-based methodology including dynamic safety analysis to support architectural decisions of drivetrain systems in the early design process is presented. Further, the proposed methodology is applied to examine feasible drivetrain design variants with respect to their fail-operability, relative acquisition cost, and relative energy efficiency. The results show that a high degree of fail-operability can be achieved either with two electric axles with one electric drive each or one electric axle with two electric drives on the same input shaft of the transmission. Drivetrain topologies with two electric axles and clutches, disconnecting the faulty parts, are recommended when mechanical faults are also considered. Furthermore, drivetrain topologies with multiple electrical machines show benefits with respect to energy efficiency by minimizing the losses through optimal torque distribution.

Christian Ebner, Kirill Gorelik, Marcel Maier, Rainer Walter, Christian Thulfaut
##### 48V-CityRoadster – Safety Extra Low Voltage Traction in the Stuttgart Metropolitan Area

Basic passenger cars with SELV (Safety Extra Low Voltage) traction drive are a promising – but barely investigated – alternative for emission-free individual mobility in urban metropolitan areas. 48V traction is often associated with light vehicles and therefore is considered as unattractive, unprestigious and unsafe. To dispel these prejudices, the 48V research group of the Esslingen University of Applied Sciences has electrified an appealing Youngtimer (BMW Z3) with SELV and reached the BEV (battery electric vehicle) registration for public roads. Despite the limited traction power of about 20 kW, a Twin-Motor with free-wheel and three-speed transmission achieves a comfortable, dignified and save mobility. To limit the empty weight to 1200 kg, the battery range is restricted to 60 km, an optional range extender battery increases the range to 90 km.This contribution describes the setup of the 48V-vehicle, the longitudinal dynamics model in Matlab/Simulink as well as the comparatively low costs for conversion and maintenance from the vehicle service point of view. The traffic benefit is elucidated by real load cycles in the Stuttgart metropolitan area in comparison to modern series BEV with high voltage as well as in comparison to different combustion motor driven cars.

Oliver Zirn, Norbert Schreier

#### Hybrid I

##### Hybridization and Phlegmatization of the pHCCI Diesel Engine

The rules for emissions for road vehicles are becoming increasingly strict, which steadily raises the requirements for the operation of vehicles with purely conventional diesel engines. PHCCI diesel combustion can defuse the Soot/ $$\text {NO}_x$$ NO x gap, but optimal operation is only guaranteed at a low indicated mean pressure and low gradients in torque demand. To extend the power range in which pHCCI operation is possible, the use of additional mild hybridization is advisable. The additional degree of freedom created by the use of an electric motor makes it possible both to shift the load point of the combustion engine into the partially homogeneous range and to reduce the torque gradient. In addition, there is the advantage of being able to recuperate kinetic energy from the vehicle. In the presented approach, the implementation of hybridization and phlegmatization, both simulative and experimental, is shown and the advantages of emission and consumption reduction are described in more detail. A vehicle simulation programmed in Simulink uses the selected operating strategy to calculate the torque and speed demand on the internal combustion engine, taking into account the use of electrical energy and the limits of the e-machine. The generated torque/speed curves enable the operation of an engine test bench with parallel emission and consumption measurements. The results of various WLTC measurements show the advantage and the associated savings potential for consumption and emissions.

Jan Klingenstein, Andreas Schneider, Hans-Jürgen Berner, Michael Bargende
##### Development of a Prediction Module for a Hybrid Operating Strategy Using Geo-Data

The efficiency gain of a hybrid drive can be further improved by optimizing the torque split. However, this requires additional input data for the simulation of a prediction. The most important information here is the preceding speed and altitude profile, as these can be used to predict the torque required to handle the driving task. A prediction module developed for this purpose accesses geo-data services (e.g. here-maps) and determines various route information for the route ahead. The information includes radius of curvature, gradient angle and speed limit. These are processed in the prediction module and used to determine the speed ahead. Based on this speed profile, the online optimizing operating strategy calculates the torque split of the hybrid powertrain for the prediction horizon so that lower fuel consumption is possible. Additional constraints such as a reduction in engine state changes, maximum torque gradients or a desired battery state of charge are taken into account. Through online optimization, the operating strategy also reacts to unpredictable variables such as unexpected route changes or deviations from the predicted speed profile.

Christian Riegelbeck, Alexander Stalp, Daniel Schade, Christian Beidl
##### Innovative, modular serial hybrid concept for a highly efficient, clean automotive powertrain

In order to reduce traffic-related emissions of both greenhouse gases and pollutants, new powertrain concepts are necessary. Phlegmatised internal combustion engines as part of hybrid powertrains offer a significant potential for efficient, clean and affordable mobility. In this paper, a modular and scalable serial hybrid powertrain concept is presented. Phlegmatisation enables the use of regenerative fuels in innovative combustion processes, such as Prechamber Combustion (PCP) or Reactivity Controlled Compression Ignition (RCCI). Functional requirements regarding vehicle performance are derived from 1D simulation, based on real driving data. Powertrain components are then dimensioned to meet the set requirements. An outlook is given towards an intelligent operating strategy, predicting power requirements on the route ahead. A Dynamic Programming approach to this predictive strategy is shown to offer considerable potential to improve efficiency, driver comfort and battery life. The basic design of the powertrain components and the operating strategy is validated simulatively.

Christian Trapp, Maximilian Böhme

#### Vehicle Simulation I

##### Highly immersive driving simulator for scenario based testing of automated driving functions

Validation of automated driving functions (SAE level 2 to level 4) has to be done scenario-based in the future. Simulation and test based methods need newly designed tools, particularly driving simulators. Today’s driving simulators based on parallel and hexapod kinematics do not provide enough motion space for many test scenarios. A wheel based driving simulator combines the advantage of a large working space with high motion dynamics. This allows to reduce false cues below the human perception thresholds in all spatial directions. With this tool the design of human-machine-interfaces can be done methodically and systematically. Requirements for homologation and technical inspection can be derived. Research on human behavioral models can be pursued (e. g. [5, 6, 7]). Finally, new opportunities arise in terms of attribute objectification in handling, ride comfort, and driveability.

Günther Prokop, Thomas Tüschen, Norman Eisenköck, Jürgen Bönninger
##### Parameter Identification Using the Model Fitting Method

Electric powertrains for passenger cars exhibit a different vibration behavior compared to conventional powertrains. These differences are characterized by significantly higher frequencies and, in particular, higher critical frequencies. This characteristic poses new challenges in regard to the testing of electric powertrains on powertrain test benches. Furthermore, the requirements relating to test benches and the methods are also changing in this case. The vibration behavior in particular is worth mentioning here. Vibration measurement technology is already used on powertrain test benches for machine and device under test (for short DUT) monitoring. In order to further develop the existing test bench technology and thus make it fit for the future, it is necessary to know information regarding the energy transfer paths of mechanical vibrations from unbalance excitations of the test bench machines.Starting from a simple model of a test bench machine as a multi-mass spring-damper system, this paper uses the model fitting method to demonstrate the determination of model parameters from vibration measurement data. The model fitting method is based on the least squares method - it is a minimization problem. The system’s model equations are determined and the experimental observations are measured. The differential equations of motion of the multi-mass spring-damper system are used as the model equations. For the solution of the differential equations, several approaches were compared and finally one approach was implemented.Based on an existing simplified vibration model of a test bench machine, sought-after model parameters could be identified and plausibilized from vibration measurement data using the model fitting method.

Alfons Wagner, Hans-Christian Reuss, Lukas Brandl
##### Simulation of Telecommunication and Automotive Behavior in real time

Safe autonomous driving requires close coordination between vehicles. This requires a reliably high quality of communication for advanced autonomous driving scenarios. Only with the introduction of the concept of network slicing in the next generation cellular mobile radio network (5G), radio resources can be reserved exclusively for V2X communication. However, the fundamental problem of wireless communication, the high variance of the achieved quality of service, remains. Fluctuations in channel attenuation and/or utilization lead to message delays or interruption of communication. The vehicle coordination can be done implicitly by using the sensors installed in the vehicle (e.g. LIDAR, ultrasound, radar) or explicitly by wireless communication between vehicles. The paper describes a new way of coupling existing simulators for relevant aspects of autonomous driving to create a real-time simulation platform for the integrated investigation of V2X communication in realistic scenarios. In this presentation, the developed simulation setup as well as simulation results concerning mobile radio influences on autonomous driving are presented.

Karl Schreiner, Michael Keckeisen, Tobias Rößler, Arthur Witt

#### Vehicle Simulation II

##### Measurement Data Acquisition for Off-Board Supported Diagnostic Functions – Arithmetic and Simulative View

This paper shows the arithmetic basics for calculation of generated bus load increase imprinted by an external diagnostic tool in in-vehicle CAN bus networks. These serve as a starting point for the mathematical and simulative consideration of a method for realization of data acquisition for off-board and model-based vehicle and system diagnostics, which was previously presented at the 5th Shanghai-Stuttgart Symposium on Automotive and Powertrain Technology in October 2021 [1]. As shown in the previous publication, standardized diagnostic services from ISO 14229 are used for this purpose to record vehicle measurements in order to implement off-board diagnostic functions. By means of the derived functions, the potential of combination of UDS services and advantages of parallel diagnostic communication of an external diagnostic tool with several vehicle ECUs can be demonstrated in arithmetic form. The desired method offers the possibility to collect data from vehicle with the efficiency of the calibration and measurement protocol XCP and with a significantly lower risk of disruption of in-vehicle communication. As a result, the method can be used for data acquisition in dynamic operation in production vehicles.

Andreas Heinz, Hans Christian Reuss

#### Vehicle Dynamics I

##### Investigation of the Influence of Vehicle Payload on Rollover Behavior

Rollover behavior is a complex phenomenon that has gained importance for the development of SUVs. As part of a cooperation project between Audi AG and TU Dresden, previous works have focused on developing a new methodology of rollover behavior analysis. Subsequently, this paper demonstrates the application of this methodology to analyze the effects of customer loading situations on the vehicle. A systematic approach to derive loading models for the vehicle development process and a method to implement loading models in a validated simulation environment are presented. Furthermore, rollover behavior is discussed, and consequential the most important loading model is identified using simulation and the introduced cause and effect chains methodology. Furthermore, this paper focuses also on the stringency of applying loading models in the development process considering vehicle testing procedures and conditions.

Christoph Ludwig, Fan Chang, Matthias Frost, Christian Schimmel, Günther Prokop
##### Chassis Concept for Large Load Ranges with Integrated Level Control for the U-Shift Project

In the automated, driverless, electric vehicle concept U-Shift, a new type of mobility is created by separating a vehicle into a drive module and a transport capsule. The autonomous driving module, known as a driveboard, is able to change the transport capsules independently and thus serves to transport both people and goods. The wide range of possible capsules poses great challenges for the development of the driveboard and especially the chassis.A novel chassis concept with integrated level control for the driveboard is presented, which masters the above-mentioned challenges. For the front axle, a solution with a combination of a subframe and a lifting device is used. A new design approach is used on the rear axle. As a special feature, the entire load range can be covered by the same mechanical spring-damper unit. The forces acting between the body and the wheels are adapted by exploiting geometric and physical relationships. In addition to the load adjustment, the presented chassis concept allows a level control and thus the lifting and lowering of the body of the driveboard down to ground level. Therefore, no further lifting devices are necessary for changing the capsule and, for example, for loading and unloading capsules that have been lowered to the ground.

Fabian Weitz, Michael Frey, Frank Gauterin
##### The Future of Vehicle Development Using Virtual Prototypes and an Interconnected Software Infrastructure

Today, the biggest shifts in the automotive industry do not take place in the traditional fields of vehicle or mechanical engineering anymore but are rather located in the areas of software and the respective control units. The digitalization of vehicles is particularly prominent in automated driving, V2X and over-the-air (OTA) software updates, which are now in series production. With OTA updates, the driver can access further developments as well as entirely new functions on demand at the touch of a button. At the same time, this also leads to the vehicle being unique and constantly evolving, which results in exploding costs and efforts for developers in validation and release processes. The purpose of this paper is to address how these changes impact current and future development methods and processes. It outlines how to manage the challenges and complexities: For example, with virtual prototypes, the use of continuous integration, testing and development (CI/CT/CD) throughout the entire product life cycle and massive scaling using high-performance computing (HPC) combined with the cloud technology. Furthermore, the paper illustrates how the associated infrastructure as well as work processes (e.g. provision of data, virtual prototype management, etc.) can be organized in symbiosis with agile software development and with the help of suitable software tools.

Alexander Ahlert

#### Hydrogen Powered Powertrains

##### Automated Design of Fuel Cell Electric Vehicle Drive Systems

Regulations in multiple countries aim at reducing the greenhouse gas emissions of the transport sector. Increased vehicle electrification is an important aspect regarding the reduction of emissions. Besides battery-electric vehicles, fuel cell electric vehicles (FCEV) also offer locally emission-free mobility. FCEV only recently entered the market and experience in development is limited. To overcome new technological challenges induced by the complex interrelations in FCEV drive systems, a methodology for the automated design of fuel cell drive systems is developed. By coupling a multi-objective optimization heuristic with a scalable techno-economic FCEV model, a high-performance validation environment is generated. This new method, implemented in the early stage of product generation engineering, enables developer to identify ideal configurations of FCEV drive systems, satisfying customer demands despite the limited experience available in development and validation.

##### Hydrogen Powertrains: A Comparison Between Different Solutions for an Urban Bus

In the compelling need for the decarbonization of the transport sector, hydrogen could play a crucial role, especially in heavy duty applications where the limited specific energy of chemical batteries can significantly reduce either the payload or the operative range. Moreover, the possibility to use Hydrogen not only within Fuel Cells (FCs) systems but also as a fuel in Internal Combustion Engines (ICEs) makes it even more attractive for future sustainable transport systems. In such a framework, this work aims to compare, through numerical simulation, different hydrogen powertrain configurations designed for an urban bus application. In particular, a series hybrid architecture was chosen as a reference considering three different technologies for its Auxiliary Power Unit: two internal combustion engines fuelled with Diesel and Hydrogen respectively, and a Fuel Cell featuring almost the same power level of the internal combustion engines. The study was carried out in real world driving conditions and the results were also compared with the ones of a conventional diesel powertrain. In particular, the numerical analysis highlighted an evident gain in terms of fuel consumption and overall efficiencies for both FCEV and H2-ICE, with respect to conventional and hybrid diesel powertrains. Based on the present results, further developments will be devoted to the optimization of the hybrid control strategy for a cost-effective exploitation of the hydrogen fueled configurations.

##### Modular fuel cell system test bench for the regional supplier industry

Fuel cell technology is a key in the use of green hydrogen and to decarbonisation in general. A power train with fuel cells (FC) shows its advantages over battery-electric drives when the load profile primarily requires constant power and high availability based on short refuelling times. In addition, higher system efficiencies can be achieved with FC than with the combustion of hydrogen in a gas engine. [1]In the project “Modular fuel cell system test bench for the H2 region Schwarzwald-Baar-Heuberg”, a fuel cell system test bench with 30 kW electrical power was built in cooperation with the Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) and the industrial partners EKPO and ETO MAGNETIC. The objective is to test FC system elements in order to contribute to the development of products suitable for large-scale production along the entire value chain and the components of the FC system. [2]The concept of a modular system test bench and an outlook for future development perspectives will be presented.

André Bürger, Frank Allmendinger, David Degler, Markus Jenne, Mark Bittmann, Sven Roos, Joachim Scherer, Thomas Kiupel
##### Energy Efficiency in Drivetrain Development in a Mini-Grid with green H2

In the development of combustion engines for Power-to-X costs for the test bench technology and especially for the fuel, increase enormously with the engine size, so that the depth of testing has to be reduced relative to the required lifetime or durability. If a H2-powered combustion engine is braked by means of a generator, usable electricity is generated from H2. As H2 is also the source of energy in a fuel cell system, both may be combined with an electrolyser, which in turn produces H2 for use in this circuit. This operating practice enables it to produce H2 very cost-effective, to minimise the purchase of grey H2 and electricity as well as to run engine and fuel cell tests with green H2 fuel.In a next step the current Mini-Grid, which includes a local H2 storage system will be enlarged by a multiplication of the electrolysers and completed by a trailer station. In the near future up to 6 larger H2 tanks and 3 further trailer sites are planned.However with regard to the limited H2-quantities high-resolution measurement techniques of IAVF Antriebstechnik GmbH may help to obtain more and better assignable results from engine and fuel cell tests, save costs and development time also in the future.

Bernhard Kehrwald, P. Berlet, F. Frischholz

#### Combustion Engines: New Approaches

##### High Efficiency Net Zero CO2 Hybrid Powertrain

IAV has developed a dedicated hybrid high efficiency demonstrator engine equipped with it’s Phase Change Cooling (PCC) technology, low friction and a high compression ratio combustion process to show the overall potential of a biofuel compatible plug in hybrid electric powertrain that combines emission free short range mobility with CO2 neutral long range capabilities. The paper will give an overview on the engine design and the first performance results at the test bench.

Thomas Arnold, Jan Böhme, Christoph Danzer, Matthias Krause

#### Software Engineering

##### Automotive Systems Engineering: Experiences and Guidance

For decades we have learned a magic triangle has three poles, namely quality, cost and time. With the new normal we see a shift towards a new magic triangle. Participants in the 2022 Vector trends survey observe a new magic triangle with three major challenges [1], namely.

Christof Ebert, Frank Kirschke-Biller
##### Enhancing Ground Truth for Digital Twins by Complete and Real-Time Upload of Vehicle Signals

The constant market pressure in the automotive industry has led to significantly shorter development cycles and enormous product diversification. This presents vehicle manufacturers with the challenge of handling the high level of complexity. Not only does the system's susceptibility to errors increase, but the vehicle's networked structure also makes troubleshooting difficult.Digital Twins are one approach to overcome these challenges. They replicate the real vehicle and form the basis of virtual insight studies – how will the vehicle behave in a particular situation, why does it do so? But the question arises where the necessary data comes from to create accurate simulations.The presented method developed at FKFS is intended to contribute to the improvement of the data basis of Digital Twins. For this purpose, it is first motivated what amount of data is generated in the vehicle during test drives and why it is useful for the virtual mapping of the vehicle. It can be shown that the current as well as future infrastructure will not be sufficient to completely and continuously transmit the large amount of data being accumulated during test driving. The presented method is dedicated to a more efficient data transmission of vehicle signals, which is characterized by significantly improved compression ratios compared to conventional transmission protocols.

Lorenz Görne, Hans-Christian Reuss, Ralf Sauerwald

#### KI - Deep Learning I

##### AI-based Parameter Optimization Method
Applied for Vehicles with Dual Clutch Transmissions

The drivability of a vehicle is strongly affected by its transmission. Especially dual clutch transmissions (DCT) offer the chance of a comfortable drivability (e.g. jerkless shifting) and high efficiency but come with the drawback of a high control effort for clutch engagement. Since particularly at low speeds the transmission behavior must meet the intention of the driver (drivers tend to be more perceptive at low speeds) the control of the launch behavior is crucial. The functions to control the behavior are typically developed using model-based programming languages and offer the possibility to influence the behavior with control parameters. Calibration engineers set these parameters at different ambient conditions to comply with customer requirements. Therefore, costs are increasing with increasing control opportunities. An approach for decreasing these costs is to automate the optimization of the calibration parameters. Several approaches have already been introduced but some suffer from lack of stability or time efficiency. Hence, to optimize these parameters a procedure is illustrated where a target state is approached with a hybrid solution of reinforcement learning and supervised learning to overcome existing drawbacks.

Marius Schmiedt, Andreas Pawlenka, Stephan Rinderknecht
##### Validation Environment for Deep Reinforcement Learning Based Gear Shift Controllers

In conventional development processes, the control of gearshifts in automatic transmissions consists of parameter maps for open loop control and subordinate PI controllers to achieve desired target trajectories. This control approach requires tedious manual tuning by experienced engineers. Deep reinforcement learning (DRL) can be used to train neural network based controllers achieving comparable results to conventionally developed gearshifts on a transmission test bench. This article presents the validation environment (VE) with the following validation configurations (VCs) required for this comparison: Simplified transmission simulation and complete vehicle simulations, transmission test benches with simulated residual vehicle as well as test vehicles with rapid prototyping control for the transmission. The validation objectives, the test bench and common interfaces are discussed. Furthermore, several Key Performance Indicators (KPIs) as evaluation criteria for gear shift criteria are presented and checked for suitability. Two methods for calculating the correspondence between the VCs are presented, including the dynamic time warping (DTW) method. The validity of the VCs and KPIs are shown using preliminary results.

Stefan Altenburg, Katharina Bause, Albert Albers
##### Data-Driven Automotive Development: Federated Reinforcement Learning for Calibration and Control

The importance of data-driven methods in automotive development continuously increases. In this area, reinforcement learning methods show great potential, but the required data from system interaction can be expensive to produce during the traditional development process. In the automotive industry, data collection is additionally constrained by privacy aspects with regard to intellectual property interests or customer data. Suitable reinforcement learning approaches need to overcome these challenges for effective and efficient learning. One possible solution is the utilization of federated learning that enables learning on distributed data through model aggregation. Therefore, we investigate the federated reinforcement learning methodology and propose a concept for a continuous automotive development process. The concept contributes separated training loops for the development and for the field operation. Furthermore, we present a customization and verification procedure within the aggregation step. The approach is exemplary shown for an electric motor current control.

Thomas Rudolf, Tobias Schürmann, Matteo Skull, Stefan Schwab, Sören Hohmann
##### Make or Buy Strategy for AI in Automotive: How Much “Make-AI” is Necessary to Succeed?

Artificial Intelligence (AI) offers huge improvements in the way cars are developed, especially for autonomous vehicles, innovative user interfaces and predictive maintenance. To make that a reality, companies face the question: Make or buy of AI? To be more precise: How much “Make AI” should a company do to benefit best from these opportunities? Experience from non-AI systems is that companies need to be able to specify, integrate and test acquired content in the context of the system. For AI, the make or buy decision has additional important dimensions such as the degree to which the acquired learning module is trained by the buyer, and to which own data is used instead of publicly available or supplied data to train it. Competencies, resources, cost, value creation and the access to domain knowledge that one may open to a supplier (that would be better kept for the company itself) are additional strategic aspects of the decision. Several levels of “Make-AI” are defined and evaluated, ranging from “Black Box AI” to “Complete Responsibility for Design, Coding and Data”. These levels are evaluated concerning specification, data collection and preparation, implementation, integration, SW test, system test, Safety/SOTIF/ISO TR 4804 evaluation as well as strategic criteria. The result guides practitioners and management to select the appropriate level and benefit best from the huge opportunities with AI.

Ulrich Bodenhausen

#### KI - Deep Learning II

##### Cloud-Based Predictive Diagnosis Using Machine Learning for Automotive EPGS

This research work presents a unique cloud-based predictive diagnosis technique using machine learning. The main role of this bidirectional communication system is to exchange measurement data and information about the state of health of the traction battery of an electric vehicle. The state of health and functionality of the traction battery, affect directly the performance and efficiency of the vehicle. Therefore, self-diagnostic is an important function, which, needs to be developed within the vehicle of the future. In this work, the predictive diagnosis is implemented over the cloud, where models to predict the state of health of the traction battery are developed using machine learning algorithms. The models are created and trained based on previous measurement that obtained during the normal operation of the vehicle. Moreover, the cloud communicates with the vehicle, the resulting information indicating the state of health, which is then provided to the end user at the back-end. The vehicle in this work is equipped with a modular and wireless communication interface for data acquisition and recording and provides the required measurement for further processing and evaluation over the cloud. This system provides a complete solution and an interactive self-diagnostic service using machine learning and without the need for extensive measurement systems and computational capacity.

Alia Salah, Omar Abu Mohareb, Hans-Christian Reuss
##### Reducing Fuel Consumption by Virtually Testing an Engine with AI

Among the multiple applications of machine learning for engineering and product development, we have recently used the Monolith AI platform to perform what we call ‘virtual testing’. Test campaigns can be expensive, but also time consuming. And sometimes, after all tests are completed, one might realise that they would have liked to make more tests. That is where virtual testing can help. The concept is to train machine learning models on existing test data and use the trained models to predict the outcome of other—virtual—test campaigns.This has multiple applications: i) one can virtually predict tests that could have been done and save the cost and the time of those tests, and ii) one can virtually predict tests that cannot be done at that time, to gain more insight on potential/future designs and help deciding on the best strategy.These two applications were explored on test data for engine calibration provided by Kistler, and in both applications insights could be gained by the engineering team. For both applications, the key advantage here is that although engineers might guess the expected trend of a test (e.g., less friction yields lower fuel consumption), such virtual test campaigns will add a missing yet critical piece of information, which is a quantitative value. Now the engineer knows for instance that the product can consume 2 %, or 0.7 % less fuel, and they can quickly make appropriate decisions.

Joël Henry, Tilmann Oestreich
##### Development and Testing Autonomous Vehicles at Scale

Developing and testing autonomous driving (AD) systems requires the analysis and storage of more data than ever before. Clients who can deliver insights faster while managing rapid infrastructure growth will be the industry leaders. To deliver these insights faster, the underlying IT and cloud technology must support both new big data as well as traditional applications with security, reliability, and high-performance. To handle massive, unstructured data growth, the solution must scale seamlessly while matching data value to the capabilities and costs of different storage tiers and types.

Frank Kraemer

#### Combustion Engines: Modeling

##### Virtual Development of a New 3-Cylinder Natural Gas Engine with Active Pre-chamber

The path to the decarbonization of transport sector goes by the integrated use of different technologies, including natural gas engines, which represent an immediate and cost-effective solution in cutting CO2 emissions, thanks to the higher H/C ratio compared to commercial fuels. However, the engine design faces a number of challenges including the need for power density, cold start, combustion efficiency, emissions, while remaining profitable for application in commercial vehicles. With these constraints in mind, a consortium of different partners tackled the development of such an engine, financed by BMWI and resulting in a project called MethMag.Considering a gasoline engine of comparable power targets as a benchmark, the virtual development led to the design of a new combustion chamber, high-tumble channels, and a new piston, after optimization of the valve strategy, by using a full-variable valve train. In addition, different injector positions, and injector types were evaluated. Direct injection below intake valves was selected in combination with an active pre-chamber. The last was specifically designed for this engine, with an hollow-cone conventional gasoline injector and cooling possibility. The investigation of the different design combinations was possible using the fast response 3D-CFD-Tool QuickSim, developed at FKFS.The resulting single-cylinder engine is currently being manufatured, and it will be installed at Fraunhofer ICT for validation and further refinement. Following the performance prediction of the first manufactured geometry, the engine can operate ultra-lean up to λ ~ 1.8, with indicated efficiency higher than 42%.

Antonino Vacca, Marco Chiodi, Michael Bargende, André Casal Kulzer, Sebastian Bucherer, Paul Rothe, Ivica Kraljevic, Hans-Peter Kollmeier, Albert Breuer, Helmut Ruhland
##### CFD Investigation of a Burner-base Heating Strategy to Speed up the cold Start Transient of ICEs

The upcoming emission legislations are expected to introduce further restrictions on the admittable level of pollutants from vehicles measured on homologation cycles and real drive tests, requiring the implementation of novel strategies to speed-up the light-off of the reactions occurring in the after-treatment system to comply with the new limits. This paper focuses on the evaluation of the potential of a burner system, which is activated before the engine start to generate a high temperature gas stream to promote a fast heating of the substrate. A CFD model has been developed to investigate the light-off of the reactions during the initial operation of the burner and the subsequent start of the engine. The model, developed on the basis of the OpenFOAM code, resorts to a multi-region approach, where different meshes are employed to describe the fluid domain and the solid regions, namely the catalytic porous substrates and the metallic walls constituting pipes and canning. Specific submodels are implemented to consider flow resistance, heat transfer, mass transfer and catalytic reactions occurring in the catalyst region. The CFD framework has been initially validated on the experimental data acquired on the test bench. The methodology has been then applied to the preliminary analysis of the catalyst light-off at engine cold start, considering a full exhaust line equipped with burner-like system.

Gianluca Montenegro, Augusto Della Torre, Loris Barillari, Angelo Onorati

#### E/E Architecture

##### Park Systems Evolution Out of Vehicle Architecture Evolution

In the year 2007 came on the mass market the first semi-automatic parking system for passenger vehicle with automatic parking space detection and lateral control of the vehicle (steering).The so-called Gen1 system could only propose parallel parking of size vehicle+1.4m. Today we the Gen4 of it is available proposing full-automated parking for many parking space types and even possible to run in a remote manner (smart device controlled).The development of parking systems is highly linked to the evolution of the passenger vehicles over the last decade in regards to their components and architecture.The paper first goes through the benefit of steady, better performing components like ABS Sensors, Steering systems and global powertrain concepts including automated gear shifting. Then it will highlight the chances of using on-board sensing sensors while relying on data exchange across the vehicle network(s) via gateway(s) and mandatory time synchronisation concept. The increase of the power computation, network bandwidth and the size/resolution of interior display do play a significant role in boosting global park system capabilities and so the trustiness of the end user.Finally, it will propose some possible outlook to the future of low speed manoeuvring systems while considering the current vehicle evolution trends toward domain- and zonal controllers as well the introduction of AI for such driver assistance systems.

Nicolas Jecker
##### Certificate-based Safety Concept for Future Dynamic Automotive Electric/Electronic Architectures

Driven by the automotive megatrends of connectivity, automation, and shared mobility, the electric and electronic architecture (E/E architecture) of future cars is undergoing a paradigm shift from hardware towards software-based approaches, leading to a service-oriented architecture (SOA). Therefore, the increasing use of software will play a crucial role in the future automotive industry. New possibilities of increasing connectivity and updates over the air enhance the advantages and need of a SOA. At the same time, new opportunities for the after-sales market can be derived, as functions can be purchased on a modular basis. Introducing upgrades within the vehicle’s life cycle leads to the difficulty that not the entire configuration of the E/E architecture is known during the development process, which leads to one of the biggest challenges in terms of safety.After investigating a general safety concept for an open adaptive system, we transferred the approach to the automotive context and demonstrated its applicability. At its core, the concept is based on safety certificates that are conditionally specified by the current system configuration. Considering ISO 26262 and the existing safety mechanisms of static E/E architecture, we derived the certificates’ content. During the continuous evolution, the overall system is certified by the sum of the safety certificates of its subsystems. Thus, this concept enables a shift of the safety analysis from the development phase to the life cycle.

Felix Krauter, Marc Schindewolf, Eric Sax
##### Zonal Network Architecture and CAN Networks

Future in-vehicle network architectures will make use of the zonal network approach. They will comprise different network technologies. One of them is the currently dominating CAN data link layer and related higher-layer protocols. Because Ethernet-based seems to be the preferred backbone network, the sub-layered CAN-based network needs to be integrated seamlessly into TCP/IP environments using SOME/IP as application layer approach, for example.

Holger Zeltwanger

#### Charging

##### Wireless Charging as Key Technology for Comfortable Charging from End Customer Perspective

The last years were driven by a huge sales momentum of plug-in hybrid and battery electric vehicles. New models and various subsidies increased the global production in 2021 up to 6.3 million vehicles. For the daily use of these vehicles, unreliable and uncomfortable charging solutions are an obstacle for consumers. This paper is analyzing how automated charging systems could enhance the e-mobility customer experience. In addition, automated charging will become mandatory if automated vehicles with autonomous parking functions will be launched. Independent of the driving mode, charging processes with automated identification, energy management and billing make manual customer actions unnecessary. To clarify the advantages and disadvantages of automated charging systems, a comparison of 10 different customer criteria was done. From base requirements like standardization to performance requirements like the charging power and cost, the technical characteristics of automated charging systems compared to the status quo manual conductive charging could be shown. Inductive wireless charging systems enable a comfortable and reliable charging solution which is needed to further simplify the daily recharging of battery electric vehicles and motivate plug-in hybrid vehicle owner towards more pure electric driving.

Dennis Mehlig, Volker Schall, Christopher Lämmle
##### Efficient Charging of Electric Vehicles by intelligent Load Management

Power generation and distribution to electric vehicle charging points requires investment in the energy sector and infrastructure. Studies show that the expansion is technically and financially possible. The prerequisite is that charging infrastructure and electric vehicles support intelligent and dynamic load management.A communication system that connects all partners in the system supports the implementation of the functions for successful grid integration: charging and load management, authorization, payment systems, bidirectional charging, e-roaming and value-added services. For all interfaces existing in the overall e-mobility system, there are standards for communication protocols that support the above functions through the specified messages and data elements. In this way, tariff tables, maximum possible charging power can be transmitted and the desired scheduling for the charging process can be communicated by the vehicle.Efficient solutions for intelligent load management take into account local as well as temporary conditions, e.g. residential area/parking garage, temporal availability of green electricity. Optimizations can be implemented locally through suitable parameterization. Availability and demand of electricity are in balance.

Ursel Willrett

#### Battery II

##### Battery Development and Testing including Simulation and Function Development at ElringKlinger

At ElringKlinger, we think that battery electric vehicles will play an increasingly important role in the future. Therefore, we develop high-voltage battery modules and packs as well as their components like cell contacting systems. However, we also think that it will be a key issue for future vehicles to know how battery systems behave under different loads over their lifetime. For this reason, the development of robust battery management systems (BMS) algorithms such as state of charge, state of health, and state of performance prediction is becoming more important. In addition to validation tests, the development also includes the construction of simulation models and the performance of service life tests. For the modules, potential customers need to know, for example, how many full cycles they can achieve under different loads. For this reason, we carry out cyclization of the modules at different loads and temperatures over their service life. For the development and parameterization of the BMS state functions, which include the determination of the state of charge, the state of aging, and the performance prediction, it is also important to know how the cell, module, or system behaves over its lifetime. However, for the estimation of an application-related aging behavior, we also perform the cyclization with a WLTP load profile. Therefore, we use single-cell tests to build up simulation models for the cells and the BMS functions.

Lars Weller, Pierre Freundt, Moritz Pausch, Joachim Buck
##### 48 V Coupling of Traction and PV-Storage Battery

Coupling battery electric vehicles (BEV) with photovoltaic (PV) powered stationary storage can significantly increase the energy efficiency of traction power supply. This applies especially to BEV and PV storage at safety extra low voltage (SELV) level e.g. 48 V. This paper describes an under-complex – but still suitable for everyday use - direct coupling and compares it to the usual BEV coupling via the 230 V AC grid. For this purpose, a simple equivalent circuit for analytical charging efficiency determination as well as a much more detailed MATLAB-Simulink model of the direct coupling is derived and validated for real BEV. This enables the quantification of the everyday benefits for different mobility scenarios. For LiFePO PV storage systems that are slightly larger than the traction battery, the efficiency advantage of direct coupling compared to coupling via the AC grid is about 15%, based on 30–40 average kilometers per day. For longer periods of standstill during the day, the efficiency advantage can be as high as 20%. Direct coupling is thus an effective measure to use decentrally generated solar energy for emission-free mobility.

Oliver Zirn

#### Battery I

##### Automated Optimization of a Cell Assembly Using Format-Flexibly Produced Pouch Cells

The production of variable cell formats can offer advantages compared to standard formats. The flexibility of the cell format results in new degrees of freedom, whereby a large number of possible arrangements and interconnections of the cells can be realized in a for the battery system available installation space of a specific application. This flexibility also results in an increase and variety of solutions, so that the development of a method supports both the developer in the synthesis, taking into account different, functionally relevant boundary conditions, and in the evaluation of the system properties. Therefore, the authors present a method that allows an automated optimization of the topology of a battery system considering the arrangement, interconnection logic as well as resulting energy and power of the battery system.For this purpose, a parameterization of the cell modules with derived product requirements such as voltage level and cooling variants is first performed in order to subsequently perform a scan of the installation space and thereby determine potential arrangements of the cell modules. In order to optimize the overall system, the individual module arrangements are then evaluated on the basis of their interconnection options and the degree to which the installation space is filled. In addition, the resulting interconnection topology is mapped in an electrical model, which enables an evaluation of the usable performance under a defined load.

Philip Müller-Welt, Konstantin Nowoseltschenko, Charlène Garot, Katharina Bause, Albert Albers
##### Field Data Analysis of a Commercial Vehicle Fleet in Relation to the Load of the HV Battery

In the course of the accelerated transformation towards regenerative energies, electric mobility is increasingly gaining importance. A central aspect in the development of electrically powered vehicles is the design of the traction battery. In this context, the specification of the possible loads on this component is essential in order to calculate the associated load capacity and thus determine the resulting lifetime.For this purpose, a customer-oriented field study was carried out with 100 commercially used battery-electric transport vehicles from various companies in the courier, express and parcel service sector, ride sharing and vehicle rental over a period of one year. By installing telemetry devices, time-series of battery and vehicle states during operation were recorded in addition to diagnostic data. This provides new insights into the commercial use of battery electric transport vehicles and supports the determination of loads on the battery system in real operation.The aim of this research is to develop a method for qualitative evaluation with regard to battery load based on field data. Within the scope of this publication, the general approach of the method as well as first analysis results of battery operating conditions and vehicle usage are presented.

Kerstin Hadler, Jens Michalski, Christoph Schuler, Jörg Kleemann, Bernard Bäker

#### Reports from FVV Projects

##### Exhaust Gas Pulsation and Turbocharger Interaction

Evaluating the interaction between turbocharger and engine at an early design stage could further reduce development time and cost. A Hardware-in-the-Loop (HiL) setup allows testing automotive turbochargers on a hot-gas test-bench at conditions close to the operation on the internal combustion (IC) engine. The arrangement contains pulse generators upstream of the turbine and downstream of the compressor to approximate flow conditions typical for an internal combustion engine. The setup is controlled by a real-time engine simulation model, which calculates the thermodynamic boundary conditions to be imposed on the turbocharger depending on the measured quantities. The concept was compared to measurements on a real engine from which the advantages and disadvantages of the setup are derived.

Dario Di-Modica, Philipp Nachtigal, Peter Eilts, Jörg Seume
##### An Empirical Based Model to Predict Ignition Delays in Partially Premixed Compression Ignition Mode

One approach to avoid the soot/NOx-trade-off in conventional diesel engines is to reach a homogeneous air to fuel mixture before the start of combustion (SOC). There are already existing solutions for homogeneous mixtures with diesel fuel. Therefore, the diesel fuel must be vaporized before injection to reach comparable brake-specific fuel consumption (BSFC) to conventional diesel combustion without significant cylinder wall and piston impingement. However, with this type of homogeneous charge compression ignition (HCCI) it is impossible to control the combustion with the injection pattern and therefore it is not practical for robust ECU mapping. Hence, HCCI has never qualified for serial use.One way to counteract the resulting variance in SOC is a partially premixed charge in the combustion chamber before SOC. A high rate of exhaust gas recirculation (EGR) with injection-controlled combustion leads to ultra-low soot and NOx emissions in a so-called premixed charge compression ignition (PCCI) application. The possibility to use state-of-the-art components such as serial injectors, pistons and EGR system of conventional diesel engines qualifies PCCI for serial use. Furthermore, the pressure gradients are comparable to those of standard diesel combustion, which leads to known combustion noise and mechanical stress of the engine.In this project, a single-cylinder Mercedes-Benz engine is used to investigate PCCI combustion at IFS University of Stuttgart. The engine is fully equipped with pressure transducers (intake, in‑cylinder and exhaust). Boost and exhaust pressure are regulated externally. The high temperature EGR rate can be varied depending on the operating points. In addition, injection strategies and intake air temperature can be set independently in a wide range to gain a maximum spread of experimental data as basis for the simulation.The goal of this project is to establish a 0D-/1D-approach to predict ignition delays (ID) for PCCI operation with multiple injection strategies. Low and high-temperature combustion can be observed in many operating points. Therefore, the physical and chemical ID of low and high temperature combustion have to be validated regarding different injection strategies, EGR rates, intake and exhaust pressures, intake temperatures and engine load.

Marvin Wahl, Simon Schneider, Michael Bargende
##### Ash Behaviour in Wall-Flow Filters

These investigations [1,2] contribute to the understanding of ash behaviour in wall-flow filters used as diesel particulate filters. The experimental part of the investigations identifies relevant parameters influencing ash deposition and ash transport in particulate filters. In the simulative part, a comprehensive numerical model is being developed which can describe the behaviour of ash particles and soot burn-off during active filter regeneration at a molecular level.Within the scope of the experimental investigations, engine ash from the field is first examined in detail. By determining essential boundary data, a suitable ash substitute is selected, which is used in a specially adapted wind tunnel to load DPF samples with the ash substitute within a short time. In parallel, ash loading of various DPF substrates is carried out under real conditions in a rapid ashing system consisting of a car engine and a fuel oil burner. Suitable analytical methods are then developed and selected, with which the loaded DPF samples can be characterized with regard to their deposition patterns. The characterizations are carried out by means of optical microscope, SEM, EDX, CT and optical evaluation methods.The main parameters influencing the ash movement are the regeneration temperature, the type of regeneration and the flow velocity. According to the results, a hot, discontinuous regeneration at high flow velocity, preceded by a continuous passive regeneration above the balance point, tends to produce a dense ash plug at the end of the channel, which increases the ash storage capacity of the DPF. Furthermore, evidence is identified that ash detachment from the wall can be implemented even with pure continuous regeneration.In the simulative part of this project, several models are developed to describe the interaction of volumetrically dissolved particles and their oxidation. By developing for the first time a method based on the decomposition of the STL geometry into segments of half-spaces, the time required for the computation can be reduced immensely. The developed models are able to represent the transport behaviour of matter in a flowed through DPF channel and also the influence of temperature on the transport behaviour.

Lukas Schneider, Matthias Kaul, Kamil Braschke, Peter Eilts, Eberhard Schmidt, Uwe Janoske
##### Backmatter
Titel
22. Internationales Stuttgarter Symposium
herausgegeben von
Prof. Dr. Michael Bargende
Prof. Dr. Hans-Christian Reuss
Prof. Dr. Andreas Wagner