TY - CHAP A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Analysis and Improvement of Engineering Exams Toward Competence Orientation by Using an AI Chatbot T2 - Towards a Hybrid, Flexible and Socially Engaged Higher Education: Proceedings of the 26th International Conference on Interactive Collaborative Learning (ICL2023), Volume 1 N2 - ChatGPT is currently one of the most advanced general chatbots. This development leads to diverse challenges in higher education, like new forms of teaching and learning, additional exam methods, new possibilities for plagiarism, and many more topics. On the other side with the development of advanced AI tools, pure knowledge will be less and less important, and demands from industry will change toward graduates with higher competencies. Education has therefore to be changed from knowledge-centered toward competence centered. The goal of this article is to use ChatGPT for analyzing and improving the competence orientation of exams in engineering education. The authors use ChatGPT to analyze exams from different engineering subjects to evaluate the performance of this chatbot and draw conclusions about the competence orientation of the tested exams. The obtained information is used to develop ideas for increasing the competence orientation of exams. From this analysis, it is visible that ChatGPT gives good performance mainly where knowledge is tested. It has, however, much more problems with transfer questions or tasks where students need creativity or complex insights for finding new solutions. Based on this result, exams and also lectures can be optimized toward competence orientation. KW - Engineering education KW - Competence orientation KW - Exam analysis KW - AI chatbot KW - ChatGPT Y1 - 2024 SN - 9783031519789 U6 - https://doi.org/10.1007/978-3-031-51979-6_42 SN - 2367-3370 SP - 403 EP - 411 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Rieger, Anna A1 - van de Par, Steven A1 - Rabl, Hans-Peter A1 - Oetjen, Arne T1 - Schärfeurteile für tonhaltige Geräusche und die Konsequenzen für die instrumentelle psychoakustische Analyse T2 - Fortschritte der Akustik - DAGA 2024, 50. Jahrestagung für Akustik, 18.-21. März 2024 in Hannover N2 - In einer vorrangegangenen Studie wurde der Einfluss psychoakustischer Parameter auf Präferenzurteile für konsonante und dissonante Geräusche untersucht. Diese Geräusche hatten die gleiche Lautheit und basierten auf einem festen Rauschhintergrund und eingebetteten hochfrequenten Tonkomponenten. Es zeigte sich, dass die Präferenzurteile eines Probandenkollektives durch ebenfalls erhobene Subjektivurteile zu Schärfe, Tonhaltigkeit und Dissonanz mit hoher Präzision vorhergesagt werden konnten.Durch das angewandte Versuchsdesign konnte diese rein auf Subjektivbeurteilungen bestehende Vorhersage mit einer instrumentellen Vorhersage der Präferenzurteile verglichen werden. Der Vergleich ergab einen niedrigeren Korrelationskoeffizienten für die modellbasierte Vorhersage, was auch durch die sehr niedrige Korrelation (R2<0,2) der berechneten Schärfe nach DIN45692 mit den Schärfe-Subjektivurteilen zu begründen war. Eine mögliche Erklärung der unzureichenden Prognose der Schärfeurteile könnte in der Bewertungsstrategie der Proband:innen zu finden sein. Für die getesteten Geräusche mit auffälligen tonalen Komponenten könnte statt der Schärfe des Gesamtgeräuschs nur die Schärfe des tonalen Geräuschobjekts berücksichtigt worden sein. Die Schärfe-Analyse der auf ihren tonalen Anteil reduzierten Signale zeigt eine sehr gute Übereinstimmung mit den Subjektivurteilen, was die Hypothese einer Trennung von Ton- und Rauschobjekten unterstützt. Es wird diskutiert, ob und wie das Paradigma der akustischen Objekttrennung in der Modellierung psychoakustischer Empfindungsgrößen Anwendung finden kann. Y1 - 2024 UR - https://pub.dega-akustik.de/DAGA_2024/konferenz?article=479 SN - 978-3-939296-22-5 SP - 1210 EP - 1213 PB - Deutsche Gesellschaft für Akustik e.V. (DAGA) CY - Berlin ER - TY - CHAP A1 - Haumer, Anton T1 - Modeling and Control Design of an Educational Magnetic Levitation System T2 - Proceedings of the 15th International Modelica Conference 2023, Aachen, October 9-11 N2 - A magnetic levitation system is a perfect educational example of a nonlinear unstable system. Only with suitable control, a small permanent magnet can be held floating stable below a coil. After modeling and simulation of the system, control of the system can be developed. At the end, the control algorithm can be coded on a microcontroller, connected to a pilot plant. KW - mechatronics KW - magnetic levitation KW - time-discrete control KW - functional mockup interface Y1 - 2023 U6 - https://doi.org/10.3384/ecp204763 SN - 1650-3686 PB - Linköping University Electronic Press ER - TY - JOUR A1 - Belyaeva, Inna A. A1 - Kramarenko, Elena Yu A1 - Shamonin (Chamonine), Mikhail T1 - Magnetodielectric effect in magnetoactive elastomers: Transient response and hysteresis JF - POLYMER N2 - Magnetodielectric properties of magnetoactive elastomers comprising micrometer-sized iron particles dispersed in compliant elastomer matrices are experimentally studied in stepwise time-varying dc magnetic fields. It is found that imposition of magnetic field significantly increases both the effective lossless permittivity of these composite materials as well as their effective conductivity. These magnetodielectric effects are more pronounced for larger concentrations of soft-magnetic filler particles and softer elastomer matrices. The largest observed relative change of the effective dielectric constant in the maximum magnetic field of 0.57 T is of the order of 1000%. The largest observed absolute change of the loss tangent is approximately 0.8. The transient response of the magnetodielectric effect to a step magnetic-field excitation can be rather complex. It changes from a simple monotonic growth with time for small magnetic-field steps (<0.1 T) to a non-monotonic behavior with a significant rapidly appearing overshoot for large magnetic-field steps (>0.3 T). The settling time to the magnetic-field step excitation can reach roughly 1000 s and it depends on the applied magnetic field and sample composition. There is also significant hysteresis of the magnetodielectric effect on the externally applied magnetic field. These findings are attributed to the rearrangement of ferromagnetic filler particles in external magnetic fields. The results will be useful for understanding and predicting the transient behavior of magnetoactive elastomers in applications where the control magnetic field is time dependent. (C) 2017 Elsevier Ltd. All rights reserved. KW - BEHAVIOR KW - composites KW - DIELECTRIC-PROPERTIES KW - hysteresis KW - MAGNETIC-FIELD KW - magnetoactive elastomer KW - magnetodielectric effect KW - Magnetorhelogical elastomer KW - MELT STATE KW - MICROSTRUCTURE KW - POLYMER DEGRADATION KW - PROGRESS KW - Smart material KW - THERMOOXIDATIVE DEGRADATION KW - TIME-RESOLVED RHEOLOGY KW - Transient response Y1 - 2017 U6 - https://doi.org/10.1016/j.polymer.2017.08.056 VL - 127 SP - 119 EP - 128 PB - ELSEVIER ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz A1 - Crotogino, Fritz A1 - Eckert, Fabian A1 - von Olshausen, Christian A1 - Teichmann, Daniel A1 - Thema, Martin ED - Sterner, Michael ED - Stadler, Ingo T1 - Chemical Energy Storage T2 - Handbook of Energy Storage N2 - Purely electrical energy storage technologies are very efficient, however they are also very expensive and have the smallest capacities. Electrochemical-energy storage reaches higher capacities at smaller costs, but at the expense of efficiency. This pattern continues in a similar way for chemical-energy storage. In terms of capacities, the limits of batteries (accumulators) are reached when low-loss long-term storage is of need. Chemical-energy storage and stocking fulfills these requirements completely. The storing itself may be subject to significant efficiency losses, but, from today’s point of view and in combination with the existing gas and fuel infrastructure, it is the only national option with regards to the long-term storage of renewable energies. Chemical-energy storage is the backbone of today’s conventional energy supply. Solid (wood and coal), liquid (mineral oil), and gaseous (natural gas) energy carriers are ‘energy storages’ themselves, and are stored using different technologies. In the course of energy transition, chemical-energy storage will be of significant importance, mainly as long-term storage for the power sector, but also in the form of combustibles and fuels for transport and heat. Not only are conventional storing technologies discussed within this chapter, but a detailed explanation is also given about the storage of renewable energies in the form of gaseous (power-to-gas, PtG) and liquid (power-to-liquid, PtL) energy carriers for electricity, heat, chemicals, and in the form of synthetic fuels. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_8 SP - 325 EP - 482 PB - Springer CY - Berlin, Heidelberg ER - TY - JOUR A1 - Sorokin, Vladislav V. A1 - Belyaeva, Inna A. A1 - Shamonin (Chamonine), Mikhail A1 - Kramarenko, Elena Yu T1 - Magnetorheological response of highly filled magnetoactive elastomers from perspective of mechanical energy density: Fractal aggregates above the nanometer scale? JF - Physical Review E N2 - The dynamic shear modulus of magnetoactive elastomers containing 70 and 80 mass % of carbonyl iron microparticles is measured as a function of strain amplitude via dynamic torsion oscillations in various magnetic fields. The results are presented in terms of the mechanical energy density and considered in the framework of the conventional Kraus model. The form exponent of the Kraus model is further related to a physical model of Huber et al. [Huber et al., J. Phys.: Condens. Matter 8, 409 (1996)] that uses a realistic representation for the cluster network possessing fractal structure. Two mechanical loading regimes are identified. At small strain amplitudes the exponent beta of the Kraus model changes in an externally applied magnetic field due to rearrangement of ferromagnetic-filler particles, while at large strain amplitudes, the exponent beta seems to be independent of the magnetic field. The critical mechanical energy characterizing the transition between these two regimes grows with the increasing magnetic field. Similarities between agglomeration and deagglomeration of magnetic filler under simultaneously applied magnetic field and mechanical shear and the concept of jamming transition are discussed. It is proposed that the magnetic field should be considered as an additional parameter to the jamming phase diagram of rubbers filled with magnetic particles. KW - BEHAVIOR KW - composites KW - hysteresis KW - MAGNETIC-FIELD KW - MODEL KW - RHEOLOGY KW - RUBBER KW - SENSITIVE ELASTOMERS KW - VISCOELASTIC PROPERTIES Y1 - 2017 U6 - https://doi.org/10.1103/PhysRevE.95.062501 VL - 95 IS - 6 PB - Amer Physical Soc ER - TY - CHAP A1 - Stadler, Ingo A1 - Bauer, Franz A1 - Budt, Marcus A1 - Heindl, Eduard A1 - Wolf, Daniel ED - Sterner, Michael ED - Stadler, Ingo T1 - Mechanical Energy Storage T2 - Handbook of Energy Storage N2 - Chemical-energy storage systems use caverns, porous storage facilities, tanks, and storage rooms to store chemical energy sources. Caverns, caves, and reservoirs can also be used to store gaseous media such as air, liquid media such as water, and solid media such as rock. The principles of mechanical energy storage are based on classical Newtonian mechanics, or in other words on fundamental physics from the eighteenth and nineteenth centuries. As a result, these types of storage are typically divided into two categories; storage of kinetic and potential energy, or storage of ‘pressure energy’. In this chapter, storage media is categorized by its aggregate state, and described by its function and application: first compressed air energy storage and then conventional electricity storage—pumped-storage plants. The chapter continues with a discussion of innovative methods of storing potential energy using water as a medium. These include artificially constructed pumped storage, pumped storage in the open sea, dam storage on rivers, pumped storage on heaps in repurposed mining areas, underfloor or underground pumped storage, and surface mine storage. The chapter concludes with a description of classical and modern flywheel energy storage systems. This age-old technology is then compared with a new concept: mechanical stored energy exploiting both pumped storage and change in the potential energy of rocks or large boulders. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_9 SP - 483 EP - 561 PB - Springer Berlin Heidelberg CY - Berlin, Heidelberg ER - TY - JOUR A1 - Belyaeva, Inna A. A1 - Klepp, Jürgen A1 - Lemmel, Hartmut A1 - Shamonin (Chamonine), Mikhail T1 - Feasibility of Probing the Filler Restructuring in Magnetoactive Elastomers by Ultra-Small-Angle Neutron Scattering JF - Applied Sciences N2 - Ultra-small-angle neutron scattering (USANS) experiments are reported on isotropic magnetoactive elastomer (MAE) samples with different concentrations of micrometer-sized iron particles in the presence of an in-plane magnetic field up to 350 mT. The effect of the magnetic field on the scattering curves is observed in the scattering vector range between 2.5 x 10(-5) and 1.85 x 10(-4) angstrom(-1). It is found that the neutron scattering depends on the magnetization history (hysteresis). The relation of the observed changes to the magnetic-field-induced restructuring of the filler particles is discussed. The perspectives of employing USANS for investigations of the internal microstructure and its changes in magnetic field are considered. KW - Anisotropy KW - Ferrofluids KW - hysteresis KW - magnetoactive elastomer KW - magnetorheological elastomer KW - Matrix KW - MIicrostructure KW - restructuring of the filler KW - ultra-small-angle neutron scattering Y1 - 2021 U6 - https://doi.org/10.3390/app11104470 VL - 11 IS - 10 SP - 1 EP - 9 PB - MDPI CY - Basel ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz ED - Sterner, Michael ED - Stadler, Ingo T1 - Definition and Classification of Energy Storage Systems T2 - Handbook of Energy Storage N2 - Energy supply always requires energy storage—either as an intrinsic property or as additional system. It is an intrinsic property of solid, liquid, and gaseous fuels, although less so of water-borne heat, but not of electricity. So to meet variable demands and supplies, heat and electricity networks usually require additional storage systems. When they are added to an energy network, should they be viewed as ‘suppliers’ or as ‘consumers’? Who is responsible for covering the costs of storage systems? To categorize storage systems in the energy sector, they first need to be carefully defined. This chapter defines storage as well as storage systems, describes their use, and then classifies storage systems according to temporal, spatial, physical, energy-related, and economic criteria. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_2 SP - 23 EP - 47 PB - Springer CY - Berlin, Heidelberg ER - TY - GEN A1 - Thema, Martin A1 - Bauer, Franz A1 - Sterner, Michael T1 - Power-to-Gas world status report T2 - International Renewable Energy Storage Conference, Düsseldorf 14.-16.03.2019 KW - Erneuerbare Energien, Klimaneutralität, Energiewende, Sektorenkopplung, Power-to-Gas KW - Power-to-Gas KW - Sektorenkopplung KW - Energiewende KW - Klimaneutralität Y1 - 2019 ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz A1 - Crotogino, Fritz A1 - Eckert, Fabian A1 - von Olshausen, Christian A1 - Teichmann, Daniel A1 - Thema, Martin T1 - Chemische Energiespeicher T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher KW - Elektrochemisches Verfahren KW - Elektrochemische Energieumwandlung Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_8 SP - 327 EP - 493 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Stadler, Ingo A1 - Bauer, Franz A1 - Budt, Marcus A1 - Heindl, Eduard A1 - Wolf, Daniel T1 - Mechanische Energiespeicher T2 - Energiespeicher - Bedarf, Technologien, Integration Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_9 SP - 495 EP - 577 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz T1 - Definition und Klassifizierung von Energiespeichern T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher Y1 - 2017 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_2 SP - 25 EP - 49 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - RPRT A1 - Sörgel, Dominika A1 - Luderer, Gunnar A1 - Emelianova, Polina A1 - Koch, Otto A1 - Timpe, Christof A1 - Bauer, Franz A1 - Sterner, Michael T1 - Kopernikus-Szenarienvergleich - Robuste Eigenschaften von Klimaschutzpfaden zur Treibhausgasneutralität 2045 und relevante Unsicherheiten N2 - Im Rahmen der vier Kopernikus-Projekte – Ariadne, ENSURE, P2X und SynErgie – wird die Transformation des deutschen Energiesystems hin zur Klimaneutralität analysiert. Im vorliegenden Bericht werden hierbei robuste Kernaussagen und relevante Unsicherheiten derjenigen Szenarien der Kopernikus-Schwesterprojekte dargestellt, die zur Zielsetzung die Klimaneutralität 2045 haben. Hierbei liegt der Fokus auf Indikatoren, die eine besonders hohe klimapolitische Relevanz haben. Y1 - 2023 UR - https://publications.pik-potsdam.de/pubman/faces/ViewItemFullPage.jsp?itemId=item_29216 PB - Kopernikus-Projekte CY - Potsdam ER - TY - CHAP A1 - Bauer, Franz A1 - Gawlik, Julia A1 - Sterner, Michael A1 - Hamacher, Thomas ED - Ausfelder, Florian ED - Du Tran, Dinh T1 - Übergreifende Energiesystemmodellierung T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen – Potentiale. 4. Roadmap des Kopernikus-Projektes P2X, Phase II Y1 - 2022 UR - https://www.kopernikus-projekte.de/lw_resource/datapool/systemfiles/elements/files/EC7C18F68BCE7C0DE0537E695E86F60F/live/document/221025_DEC_P2X4_V08_Web.pdf SN - 978-3-89746-238-0 SP - 17 EP - 35 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. CY - Frankfurt a.M. ER - TY - JOUR A1 - Gamisch, Bernd A1 - Ettengruber, Stefan A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - Dynamic simulation of isothermal and non-isothermal reduction and oxidation reactions of iron oxide for a hydrogen storage process JF - Renewable and Sustainable Energy N2 - This work aims first to develop a dynamic lumped model for the isothermal reactions of hydrogen/steam with a single iron oxide/iron pellet inside a tubular reactor and to validate the model results against the experimental reaction kinetic data with the help of our STA device. To describe the temporal change in mass, and consequently, the temporal heat of reaction, the shrinking core model, based on the geometrical contracting sphere, is applied. It turned out that, the simulation model can reproduce the experimental, temporal concentration and temperature-dependent conversion rates with a maximum deviation of 4.6% during the oxidation reactions and 3.1% during the reduction reactions. In addition, a measured isothermal storage process comprising one reduction and one oxidation phase with a holding phase in between on a single reacting pellet could be reproduced with a maximum absolute deviation in the conversion rate of 1.5%. Moreover, a lumped, non-isothermal simulation model for a pelletized tubular redox-reactor including 2kg of iron oxide pellets has been established, in which the heat of reaction, heat transfer to the ambient and heat transfer between the solid and gas phases are considered. The temporal courses of the outlet gas concentration as well as the temperatures of the gas stream and the solid material at a constant input gas flow rate and a constant reacting gas inlet concentration but different input gas temperatures are estimated. Because of the endothermic nature of the reduction reaction, the inlet reacting gas temperature shall be kept high to prevent the severe temperature drop in the solid phase and, consequently, the significant reduction of the reaction rate. Contrary to that, the oxidation process requires lower input gas temperatures to avoid the excessive overheating of the reaction mass and, consequently, the sintering of the reacting pellets. Finally, five of the previous reactors have been connected in series to explore the influence of the changing inlet gas temperatures and concentrations on the dynamic performance of each storage mass. KW - hydrogen storage KW - iron/iron oxide KW - redox reactions KW - lumped model KW - isothermal reactions KW - non-isothermal reactions KW - kinetics of reactions KW - Aspen Custom Modeler Y1 - 2023 U6 - https://doi.org/10.55092/rse20230004 N1 - Corresponding author: Belal Dawoud VL - 1 IS - 1 PB - ELSP, International Open Science Platform ER - TY - CHAP A1 - Wagner, Marcus A1 - Lehrer, Tobias A1 - Franke, Markus A1 - Al-Abadi, Ali A1 - Gamil, Ahmed T1 - A Tank Resonance Model for Power Transformers T2 - ARWtr 2022 proceedings, 2022 7th Advanced Research Workshop on Transformers (ARWtr): October (23)24-26, 2022, Baiona, Spain N2 - During the factory acceptance test, the sound levels are measured. If the measured sound levels exceed pre-specified values, modifications on the transformer’s active part and/or tank need to be conducted. Tank resonance, if occurs, at twice main power frequency and its higher harmonics is one of the main reasons of amplifying the generated sound levels. Therefore, it is preferable to know already in the design stage about the occurrence of the tank resonance and propose reliable tank solutions. The current study presents a newly developed model for calculating the mode shapes and its corresponding eigenfrequencies of the tank. Y1 - 2022 U6 - https://doi.org/10.23919/ARWtr54586.2022.9959917 SP - 7 EP - 12 PB - IEEE ER - TY - JOUR A1 - Klenk, Eva Marianne A1 - Galka, Stefan T1 - Analysis of real-time tour building and scheduling strategies for in-plant milk-run systems with volatile transportation demand JF - IFAC - PapersOnLine N2 - In modern manufacturing systems, milk run (MR) systems represent route-based, cyclic material-handling systems that are used widely and enable frequent deliveries of containerized parts in small lot sizes from a central storage area to multiple points of use on the factory floor. Usually, deliveries take place at predetermined, constant time intervals. As in real-world MR systems, the number of containers to deliver in each interval varies in the short term, peaks in the number of deliveries may lead to capacity bottlenecks and late deliveries. In this paper, we develop three alternative strategies to determine starting times of MR cycles in real-time based on the current number of delivery orders in the system aiming to better handle variations in the number of orders. We evaluate the three strategies for different system load scenarios with respect to delivery service levels, order lead times, systems utilization and necessary number of MR trains using a discrete-event simulation model. KW - Control algorithms KW - Logistics KW - Material handling KW - Milk-run systems KW - Production systems KW - Real-time decision making KW - Transportation control Y1 - 2019 U6 - https://doi.org/10.1016/j.ifacol.2019.11.517 VL - 52 IS - 13 SP - 2110 EP - 2115 PB - Elsevier ER - TY - JOUR A1 - Heberl, Michael A1 - Withelm, Christian A1 - Kaul, Anja A1 - Rank, Daniel A1 - Sterner, Michael T1 - Prospective Life Cycle Assessment of Biological Methanation in a Trickle-Bed Pilot Plant and a Potential Scale-Up JF - Energies N2 - The fluctuating nature of renewable energies results in the need for sustainable storage technologies to defossilize the energy system without other negative consequences for humans and the environment. In this study, a pilot-scale trickle-bed reactor for biological methanation and various scale-up scenarios for 2024 and 2050 were investigated using life cycle assessment. A best- and worst-case scenario for technology development until 2050 was evolved using cross-consistency analysis and a morphological field, based on which the data for the ecological models were determined. The results show that the plant scale-up has a very positive effect on the ecological consequences of methanation. In the best-case scenario, the values are a factor of 23–780 lower than those of the actual plant today. A hot-spot analysis showed that electrolysis operation has an especially large impact on total emissions. The final Monte Carlo simulation shows that the technology is likely to achieve a low global warming potential with a median of 104.0 kg CO2-eq/MWh CH4 and thus can contribute to decarbonization. KW - Ökobilanzierung KW - Power-to-Gas KW - Elektrolyse KW - Methanisierung KW - erneuerbare Energien Y1 - 2024 U6 - https://doi.org/https://doi.org/10.3390/en17092206 SN - 1996-1073 VL - 17 IS - 9 PB - MDPI AG CY - Basel ER - TY - INPR A1 - Takayasu, Anna A1 - Weikl, Simone A1 - Dahmen, Victoria A1 - Bogenberger, Klaus T1 - Impact of Travel Stress and Infrastructure Quality on Cycling Mode Share: Insights From Multimodal Trajectory and Survey Data Analysis N2 - This study explores the relationship between travel stress, infrastructure quality, and cycling mode share. Utilizing multimodal trajectory data, survey responses on travel stress, and detailed road network information with geological and bicycle facility data, the study analyzes correlations between actual and perceived infrastructure quality, travel stress, and cycling mode share, as well as the impact of travel time and distance on cycling mode share. The results indicate significant correlations between perceived infrastructure quality and travel stress levels, and between travel stress levels and cycling mode share, particularly among regular bike users. However, clear correlations between actual and perceived infrastructure quality, and between perceived infrastructure quality and cycling mode share, were not observed. Additionally, direct effects of travel time and distance on cycling mode share were not evident. From these findings, three main insights emerge. Firstly, accurately estimating cycling mode share requires considering multiple parameters beyond travel time and distance. Secondly, to implement effective measures for bicycle facilities, a detailed analysis of perceived infrastructure quality, incorporating actual infrastructure design, is crucial. Lastly, travel stress, when carefully assessed with consideration of various factors beyond infrastructure design, emerges as a key determinant of travel mode choice. These insights have significant implications for future cycling research, including the development of travel mode choice models and estimating cycling demand. The study's valuable contributions advance efforts to promote cycling as a sustainable and preferred mode of transportation. Y1 - 2023 U6 - https://doi.org/10.13140/RG.2.2.30696.85766 PB - Researchgate ER - TY - CHAP A1 - Bauer, Franz A1 - Gawlik, Julia A1 - Sterner, Michael A1 - Hamacher, Thomas ED - Ausfelder, Florian ED - Dura, Hanna Ewy T1 - Übergreifende Energiesystemmodellierung T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen – Potentiale. 3. Roadmap des Kopernikus-Projektes P2X, Phase II Y1 - 2021 UR - https://www.kopernikus-projekte.de/lw_resource/datapool/systemfiles/elements/files/CBE2878A53D522EEE0537E695E868061/live/document/DEC_P2X_II_V06_Online_small.pdf SN - 978-3-89746-236-6 SP - 19 EP - 33 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. CY - Frankfurt a.M. ER - TY - JOUR A1 - Dahmen, Victoria A1 - Bogenberger, Klaus A1 - Weikl, Simone T1 - Modellierung des Verkehrsmittelwahlverhaltens mittels erklärbarem Maschinellem Lernen JF - Straßenverkehrstechnik N2 - Die Modellierung der Verkehrsmittelwahl ist für die Vorhersage und das Verständnis des Mobilitätsverhaltens unerlässlich. Hierbei wurden in den letzten Jahren mit maschinellem Lernen vielversprechende Ergebnisse erzielt, insbesondere für XGBoost- und Random-Forest-Modelle. Aufgrund der zunehmenden Verwendung von Tracking-basierten Smartphone-Apps zur Aufzeichnung des Mobilitätsverhaltens, wenden wir diese Modelle auf einen solchen Datensatz an. Zudem analysieren wir eingehend deren Interpretierbarkeit. Wir kommen zu dem Schluss, dass das XGBoost-Modell am leistungsstärksten und dennoch erklärbar ist. Die von solchen Modellen gewonnenen Erkenntnisse können beispielsweise genutzt werden, um die Verkehrsmittelwahl für beliebige Quelle-Ziel-Paare vorherzusagen. Y1 - 2025 U6 - https://doi.org/10.53184/SVT2-2025-3 SN - 0039-2219 VL - 69 IS - 2 SP - 96 EP - 102 PB - Kirschbaum ER - TY - CHAP A1 - Reichel, Tobias A1 - Gerstner, Mathias A1 - Schiller, Leo A1 - Attenberger, Andreas A1 - Hackenberg, Rudolf A1 - Dološ, Klara T1 - A forensic analysis of GNSS spoofing attacks on autonomous vehicles T2 - Cloud Computing 2025 : The Sixteenth International Conference on Cloud Computing, GRIDs, and Virtualization, 06.-10. April 2025, Valencia N2 - Global Navigation Satellite Systems (GNSSs) are essential for modern technology, enabling precise geographic positioning in aviation, maritime shipping, and automotive systems. In the future, their role will be even more critical for autonomous vehicles, which rely on accurate localization for navigation and decision-making. However, the increasing connectivity of autonomous vehicles exposes them to cyber threats, including GNSS spoofing attacks, which manipulate location data to mislead onboard systems. As reliance on GNSS grows, so does the risk posed by spoofing attacks, making it a critical security concern. This paper describes GNSS spoofing attacks on autonomous vehicles, focusing on their detection both during and after an attack. Furthermore, we analyze data storage strategies to facilitate effective forensic analysis. We highlight the importance of position, signal, and camera data, which should be preserved to ensure a comprehensive forensic investigation. Finally, we suggest a simulation setup that enables studying which data could be used for a forensic investigation. Additionally, we examine established data frameworks and decide whether they are suitable for detecting GNSS spoofing attacks. Y1 - 2025 UR - https://www.thinkmind.org/articles/cloud_computing_2025_1_50_28008.pdf SN - 978-1-68558-258-6 SN - 2308-4294 SP - 32 EP - 39 ER - TY - JOUR A1 - Lindner, Matthias A1 - Pipa, Andrei V. A1 - Karpen, Norbert A1 - Hink, Rüdiger A1 - Berndt, Dominik A1 - Foest, Rüdiger A1 - Bonaccurso, Elmar A1 - Weichwald, Robert A1 - Friedberger, Alois A1 - Caspari, Ralf A1 - Brandenburg, Ronny A1 - Schreiner, Rupert T1 - Icing Mitigation by MEMS-Fabricated Surface Dielectric Barrier Discharge JF - Applied Sciences N2 - Avoiding ice accumulation on aerodynamic components is of enormous importance to flight safety. Novel approaches utilizing surface dielectric barrier discharges (SDBDs) are expected to be more efficient and effective than conventional solutions for preventing ice accretion on aerodynamic components. In this work, the realization of SDBDs based on thin-film substrates by means of micro-electro-mechanical-systems (MEMS) technology is presented. The anti-icing performance of the MEMS SDBDs is presented and compared to SDBDs manufactured by printed circuit board (PCB) technology. It was observed that the 35 mu m thick electrodes of the PCB SDBDs favor surface icing with an initial accumulation of supercooled water droplets at the electrode impact edges. This effect was not observed for 0.3 mu m thick MEMS-fabricated electrodes indicating a clear advantage for MEMS-technology SDBDs for anti-icing applications. Titanium was identified as the most suitable material for MEMS electrodes. In addition, an optimization of the MEMS-SDBDs with respect to the dielectric materials as well as SDBD design is discussed. KW - aerospace engineering KW - anti-icing KW - DBD PLASMA ACTUATORS KW - EXCITATION KW - FLOW-CONTROL KW - low-temperature plasma KW - MEMS KW - SEPARATION CONTROL KW - SDBD Y1 - 2021 U6 - https://doi.org/10.3390/app112311106 N1 - Corresponding author: Matthias Lindner VL - 11 IS - 23 SP - 1 EP - 17 PB - MDPI CY - Basel ER - TY - RPRT A1 - Sterner, Michael A1 - Bauer, Franz A1 - Hofrichter, Andreas A1 - Heberl, Michael T1 - Systemanalyse und -integration Power-to-X im Kontext von erneuerbarer Elektrizität als Primärenergie (SPIKE) N2 - Durch das in Paris beschlossene Ziel, die globale mittlere Temperatur auf deutlich unter 2 Grad Celsius gegenüber dem vorindustriellen Niveau zu begrenzen, ist ein Ausstieg aus der Nutzung fossiler Energieträger und Rohstoffe bis zum Jahr 2050 notwendig (WBGU 2016). Daher hat sich die Bundesregierung das Ziel gesetzt, bis zur Mitte des Jahrhunderts eine weitgehende Treibhausgasneutralität zu erreichen. Hierzu ist neben einer Steigerung der Energieeffizienz in allen Sektoren ein Ausbau erneuerbaren Energien notwendig. Dies beinhaltet hauptsächlich den Zubau von Wind‐ und Solarstromanlagen. Somit gewinnt die Sektorkopplung immer mehr an Bedeutung und wird in Zukunft eine tragende Rolle für die Defossilisierung des Energiesystems spielen (BMUB 2016). Als zentrales Element der Sektorkopplung gilt Strom, der über Power‐to‐X (PtX) sowohl energetisch im Wärme‐, und Verkehrssektor als auch stofflich in der Industrie und vor allem im Chemiesektor eingesetzt werden kann (Ausfelder et al. 2018a). Im Rahmen des P2X‐Vorhabens der Kopernikus Forschungsinitiative wird die Sektorkopplung durch die Umwandlung von Strom mittels elektrochemischer Prozesse in stoffliche Ressourcen wie Wasserstoff, Synthesegas oder Kohlenstoffmonoxid untersucht. Der Schwerpunkt liegt auf der Betrachtung der Kopplung von Strom und Verkehr sowie Strom und Chemie und der Untersuchung von Prozessen und Pfaden, die aus ökologischer, ökonomischer und gesellschaftlicher Sicht vorteilhaft sind. Eine vergleichende Einordnung in den Gesamtkontext der Energiewende mit Abwägung zahlreicher Alternativen und Konkurrenztechnologien ist dort allerdings nicht vorgesehen. Zudem werden einige relevante PtX‐Technologien wie Power‐to‐Heat nicht betrachtet. Aus diesem Grund wurden in SPIKE ergänzende PtX‐Technologiepfade aus systemanalytischer Sicht untersucht. Dies sind Power‐to‐Heat (PtH) und Power‐to‐Gas (PtG) über Elektrolyse und optionaler anschließender Methanisierung sowie die Herstellung ausgewählter Pfade der strombasierten Herstellung von Produkten der energieintensiven Industrie. Ziel des Forschungsvorhabens war die Analyse von PtX‐Technologien und Pfaden, deren vergleichende Einordnung im Gesamtkontext der Energiewende sowie die Unterstützung des P2X Roadmapping Prozesses und die Ableitung von Handlungsempfehlungen. Ein besonderer Schwerpunkt lag auf dem Einsatz von PtX im Industriesektor. Für das Vorhaben wurden Arbeitspakete (AP) erstellt, die Untersuchungen zu Technologie, Potenzial, Ökonomie und Ökologie von PtH (AP 1), PtG (AP 2), Power‐to‐Ammoniak, Power‐to‐Ethen und Power‐to‐Propen (AP 3) umfassten. Daraus wurde in AP 4 ein Systemvergleich mit Einordnung von PtX in die Energiewende durchgeführt. Auf dieser Basis und der Identifizierung regulatorischer Rahmenbedingungen für PtX (AP 5) wurde das deutsche Energiesystem samt PtX‐Pfaden in einem Energiesystemmodell abgebildet (AP 6). Die Ergebnisse flossen in das Roadmapping ein (AP 7). Zudem erfolgte ein Austausch mit den Projektpartnern und das Verfassen wissenschaftlicher Abhandlungen (AP 8). KW - Energieintensive Industrie KW - Energiesystemmodellierung KW - Power-to-Gas KW - Power-to-Heat KW - Ökobilanzierung Y1 - 2019 ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz A1 - Hofrichter, Andreas ED - Ausfelder, Florian ED - Dura, Hanna Ewy T1 - Systemanalyse von Power-to-X-Pfaden - Ergebnisse des Satellitenprojektes "SPIKE" T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X Technologien : Nachhaltigkeitseffekte - Potenziale Entwicklungsmöglichkeiten; 2. Roadmap des Kopernikus-Projektes "Power-to-X": Flexible Nutzung erneuerbarer Ressourcen (P2X) Y1 - 2019 UR - https://edocs.tib.eu/files/e01fn21/1770760199.pdf SN - 978-3-89746-218-2 SP - 145 EP - 153 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V CY - Frankfurt am Main ER - TY - JOUR A1 - Gamisch, Bernd A1 - Huber, Lea A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - On the Kinetic Mechanisms of the Reduction and Oxidation Reactions of Iron Oxide/Iron Pellets for a Hydrogen Storage Process JF - Energies N2 - This work aims at investigating the kinetic mechanisms of the reduction/oxidation (redox) reactions of iron oxide/iron pellets under different operating conditions. The reaction principle is the basis of a thermochemical hydrogen storage system. To simulate the charging phase, a single pellet consisting of iron oxide (90% Fe2O3, 10% stabilising cement) is reduced with different hydrogen (H2) concentrations at temperatures between 600 and 800 °C. The discharge phase is initiated by the oxidation of the previously reduced pellet by water vapour (H2O) at different concentrations in the same temperature range. In both reactions, nitrogen (N2) is used as a carrier gas. The redox reactions have been experimentally measured in a thermogravimetric analyser (TGA) at a flow rate of 250 mL/min. An extensive literature review has been conducted on the existing reactions’ kinetic mechanisms along with their applicability to describe the obtained results. It turned out that the measured kinetic results can be excellently described with the so-called shrinking core model. Using the geometrical contracting sphere reaction mechanism model, the concentration- and temperature-dependent reduction and oxidation rates can be reproduced with a maximum deviation of less than 5%. In contrast to the reduction process, the temperature has a smaller effect on the oxidation reaction kinetics, which is attributed to 71% less activation energy (Ea,Re=56.9 kJ/mol versus Ea,Ox=16.0 kJ/mol). The concentration of the reacting gas showed, however, an opposite trend: namely, to have an almost twofold impact on the oxidation reaction rate constant compared to the reduction rate constant. Y1 - 2022 U6 - https://doi.org/10.3390/en15218322 N1 - Corresponding author: Belal Dawoud VL - 15 IS - 21 PB - MDPI ER - TY - JOUR A1 - Hirschberg, Wolfgang A1 - Rill, Georg A1 - Weinfurter, H. T1 - Tire model TMeasy JF - Vehicle System Dynamics N2 - This paper describes the semi-physical tire model TMeasy for vehicle dynamics and handling analyses, as it was applied in the ‘low frequency tire models’ section of the research programme tire model performance test (TMPT). Despite more or less weak testing input data, the effort for the application of TMeasy remains limited due to its consequent ‘easy to use’ orientation. One particular feature of TMeasy is the wide physical meaning of its smart parameter set, which allows to sustain the identification process even under uncertain conditions. After a general introduction, the modelling concept of TMeasy is compactly described in this paper. Taking the standard tire interface (STI) to multibody simulation system (MBS) software into account, the way to apply TMeasy is briefly shown. This includes three selected examples of application. The final comments of the authors on TMPT describe the experiences and earnings received during the participation in that programme. Y1 - 2007 U6 - https://doi.org/10.1080/00423110701776284 VL - 45 IS - sup1 SP - 101 EP - 119 PB - Taylor&Francis ER - TY - CHAP A1 - Bäuml, T. A1 - Haumer, Anton A1 - Kapeller, Hansjörg A1 - Starzinger, J. A1 - Farzi, P. T1 - Impact of inverter pulse inhibition on the high-voltage supply system of an electric vehicle — A simulative approach T2 - 2011 IEEE Vehicle Power and Propulsion Conference (VPPC 2011) : Powering sustainable transportation ; Chicago, Illinois, USA, 06. - 09.09.2011 N2 - This paper deals with a simulative approach for investigating the impact of inverter pulse inhibition during field weakening operation of permanent magnet synchronous machines and asynchronous induction machines. The modelling and simulation language Modelica is used to design models for the vehicle, the electric machine and the inverter in different abstraction levels. It is shown that when using a permanent magnet synchronous machine, a sudden breakdown of the field weakening current causes induction of high voltages in the stator windings. Hence, the electric system of the vehicle has to be protected against the resulting high currents. Furthermore precautions have to be taken to avoid dangerous driving conditions because of high braking torques in an inverter fault operation mode. In the case of the asynchronous induction machine an inverter pulse inhibition poses no big problem, neither for the electric system of the vehicle, nor the driver. KW - asynchronous machines KW - Connectors KW - electric vehicles KW - Inverters KW - invertors KW - Mathematical model KW - Object oriented modeling KW - permanent magnet machines KW - power engineering computing KW - Rotors KW - synchronous machines KW - Torque KW - Vehicles Y1 - 2011 SN - 978-1-61284-248-6 SN - 978-1-61284-247-9 SN - 978-1-61284-246-2 U6 - https://doi.org/10.1109/VPPC.2011.6043159 SP - 1 EP - 5 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Jungreuthmayer, C. A1 - Bauml, T. A1 - Winter, O. A1 - Ganchev, M. A1 - Kapeller, Hansjörg A1 - Haumer, Anton A1 - Kral, Christian T1 - Heat and fluid flow analysis of an internal permanent magnet synchronous machine by means of computational fluid dynamics T2 - 2011 IEEE International Electric Machines & Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011 N2 - This paper presents a comprehensive computational fluid (CFD) model of a radial flux permanent magnet synchronous machine with interior magnets. In the CFD model the water jacket cooling and a simplified model of the topology of the distributed stator winding are considered. The heat sources of the CFD model are determined from a finite element analysis of the machine. The numerically determined temperature distributions of the machine are compared with measurement results from sensors located both in the stator and rotor. The particular focus of this paper is the analysis of the temperatures and the heat flow in the air gap and from the stator winding head and the rotor to the inner air. KW - CFD KW - computational fluid dynamics KW - Cooling KW - finite element analysis KW - interior magnet KW - permanent magnet machines KW - permanent magnet synchronous machine KW - Rotors KW - sensor placement KW - stators KW - synchronous machines KW - temperature KW - temperature distribution KW - thermal analysis Y1 - 2011 SN - 978-1-4577-0060-6 SN - 978-1-4577-0061-3 SN - 978-1-4577-0059-0 U6 - https://doi.org/10.1109/IEMDC.2011.5994651 SP - 515 EP - 520 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Schümann, Malte A1 - Morich, J. A1 - Kaufhold, Tobias A1 - Böhm, Valter A1 - Zimmermann, Klaus A1 - Odenbach, Stefan T1 - A mechanical characterisation on multiple timescales of electroconductive magnetorheological elastomers JF - Magnetism and Magnetic Materials N2 - Magnetorheological elastomers are a type of smart hybrid material which combines elastic properties of a soft elastomer matrix with magnetic properties of magnetic micro particles. This leads to a material with magnetically controllable mechanical properties of which the magnetorheological effect is the best known. The addition of electroconductive particles to the polymer mix adds electrical properties to the material behaviour. The resulting electrical resistance of the sample can be manipulated by external magnetic fields and mechanical loads. This results in a distinct interplay of mechanical, electrical and magnetic effects with a highly complex time behaviour. In this paper a mechanical characterisation on multiple time scales was conducted to get an insight on the short and long-term electrical and mechanical behaviour of this novel material. The results show a complex resistivity behaviour on several timescales, sensitive to magnetic fields and strain velocity. The observed material exhibits fatigue and relaxation behaviour, whereas the magnetorheological effect appears not to interfere with the piezoresistive properties. Y1 - 2018 U6 - https://doi.org/10.1016/j.jmmm.2018.01.029 VL - 453 IS - May SP - 198 EP - 205 PB - Elsevier ER - TY - CHAP A1 - Hackl, Andreas A1 - Hirschberg, Wolfgang A1 - Lex, Cornelia A1 - Rill, Georg ED - Bargende, Michael ED - Reuss, Hans-Christian ED - Wiedemann, Jochen T1 - Experimental validation of the Maxwell model for description of transient tyre forces T2 - 16. Internationales Stuttgarter Symposium, Automobil- und Motorentechnik N2 - Modelling and simulation of safety relevant Driver Assistance Systems (DAS) and Vehicle Dynamics Controllers (VDC) which act in standard and limit situations lead to increasing accuracy demands in the description of dynamic reactions of tyre contact forces, e.g. For that purpose, first-order approaches are widely applied in this field of vehicle dynamics and handling, which originate from Schlippe & Dietrich, were modified by Pacejka and later on refined by Rill. Y1 - 2016 SN - 978-3-658-13254-5 U6 - https://doi.org/10.1007/978-3-658-13255-2_29 SP - 401 EP - 418 PB - Springer CY - Wiesbaden ER - TY - JOUR A1 - Lang, Alexander A1 - Monkman, Gareth J. T1 - An analysis of the electrical capacitance between two conducting spheres JF - Journal of Electrostatics N2 - Many modern composites consist of dielectric polymer matrices containing embedded spherical particles. These particles can be electrically conducting and often have magnetic properties. In order to accurately model and simulate such materials, precise calculation of the electrical capacitance between identically sized spheres is required. This is of particular relevance at microscopic dimensions where many smart material-based micro devices are concerned. This may appear trivial for a small number of particles. However, many methods or their analysis appear to be questionable or not applicable at reduced dimensions. In this work, the various methods of analysis are scrutinized before being compared with both simulation and direct measurements. It is surprising to note that of the many works investigated only 3 are in close agreement with both simulation and measurement. Graphical abstract This paper deals with the precise calculation of the electrical capacitance between two conducting spheres of equal, or near equal size.The calculations have been verified by both experimental measurements and simulation. Algorithms in MatLab (Octave) format have been included in the supporting information. KW - Capacitance between spheres KW - Calculation KW - Simulation Experiment Y1 - 2020 U6 - https://doi.org/10.1016/j.elstat.2020.103518 VL - 108 PB - Elsevier ER - TY - JOUR A1 - Li, Liwen A1 - Lange, Klaus W. T1 - Planning Principles for Integrating Community Empowerment into Zero-Net Carbon Transformation JF - smart cities N2 - The adoption of the UN 2030 Agenda and the Sustainable Development Goals is a landmark in international sustainability politics. For example, Europe has set ambitious targets to achieve 100 climate-neutral and smart cities by 2030. However, numerous case studies from different countries have found that accelerating the transition to net-zero carbon emissions is easily hampered by the lack of a coherent systems framework, and that implementation gaps remain at the community level. These barriers are often due to a lack of an adequate end-user (i.e., household) input and early planning participation. This work therefore aims to improve on conventional planning methods that do not reflect innovative technologies with uncertainty and may not be applicable due to the lack of community empowerment, which is a dynamic learning and intervention opportunity for end-users at different planning stages (i.e., outreach, survey, planning, implementation, management, and maintenance). Using the lessons learned from participatory action research, whereby the author was involved as a project director throughout the planning and design process, we identified a six-step cycle principle. The steps are (1) collective action commitments, (2) local values and resource identification, (3) carbon footprint inventory, (4) optimized integration of environment, economy, and energy action plans, (5) Flexible strategic energy system plans, and (6) digital performance monitoring. Ultimately, the outcomes provide application support for policymakers and planners and stimulate community engagement to contribute to the achievement of zero net carbon emissions. T2 - Planungsprinzipien für die Integration von Community Empowerment in die Zero-Net Carbon Transformation KW - social science KW - environmental planning KW - responsible research innovation KW - public–private partnerships KW - low-carbon communities KW - participatory action research KW - collective actions Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-57765 VL - 2023 IS - 6 SP - 100 EP - 122 PB - MDPI CY - Basel ER - TY - CHAP A1 - Hackl, Andreas A1 - Hirschberg, Wolfgang A1 - Lex, Cornelia A1 - Rill, Georg ED - Spiryagin, Maksym ED - Gordon, Timothy ED - Cole, Colin ED - McSweeney, Tim T1 - Tyre type dependent transient force behaviour by means of a maxwell model T2 - The Dynamics of Vehicles on Roads and Tracks : Proceedings of the 25th Symposium of the International Association of Vehicle System Dynamics (IAVSD 2017), Rockhampton, Queensland, Australia, 14-18 August 2017 N2 - The present papers deals with the usability of an extended Maxwell model to describe the tyre dynamics during transient driving manoeuvres. In the present article, the para-metrisation process of a dynamic tyre model is investigated in a first step, using measurement data of tyre forces from a flat trac tyre test bench, (IABG 2016). Two tyre types of dimensions 255/50 R19 and 175/55 R15 are used. The practical applicability is discussed, considering the measurement procedure and the parameter optimisation process. In a second step, the performance of the dynamic tyre model is validated using measurements of manoeuvres under higher dynamic excitation. As a last step, an outlook is given on further research planned in which the presented model and parametrisation are adapted to a larger frequency range. Y1 - 2018 SN - 1351057170 U6 - https://doi.org/10.1201/9781315265506 SP - 157 EP - 162 PB - CRC Press CY - London ER - TY - JOUR A1 - Mikhaeil, Makram A1 - Nowak, Sebastian A1 - Palomba, Valeria A1 - Frazzica, Andrea A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - Experimental and analytical investigation of applying an asymmetric plate heat exchanger as an evaporator in a thermally driven adsorption appliance JF - Applied Thermal Engineering N2 - This communication presents an experimental and analytical study on the evaporation mechanism in a closed-structured asymmetric plate heat exchanger (PHE) employed as a stagnant water evaporator for the application in an adsorption heat transformation appliance. To this aim, an experimental unit is constructed, which comprises two identical PHEs, one acting as an vaporator/condenser and the second, as an adsorber/desorber. Two endoscopes are mounted inside the investigated evaporator to visualize the evaporation mechanism when performing adsorption-evaporation processes under different boundary conditions. It turned out that the evaporation mechanism is a partially covered, thin film evaporation. A heat transfer analysis is performed to evaluate the heat transfer coefficient of the thin film evaporation () inside the investigated evaporator, resulting in -values between 1330 and 160 [W∙m−2∙K−1] over the investigated adsorption-evaporation time. Correlating the obtained () to the film thickness and the wetted area results in -values between 0.34 and 0.78 [mm] and wetted to total area ratios of 0.78 to 0.16. Besides, an analytical model has been developed and introduced to correlate the overall evaporator heat transfer coefficient with the adsorption potential and the time rate of change of the water uptake. KW - Adsorption-evaporation KW - Evaporator KW - Plate heat exchanger KW - Thin film evaporation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-61115 N1 - Corresponding author: Belal Dawoud IS - 228 PB - Elsevier ER - TY - RPRT A1 - Marterer, Verena A1 - Kemeter, Dominik A1 - Lang, Andreas A1 - Dischner, Alexander A1 - Huber, Stephanie A1 - Obermeier, Maximilian A1 - Langer, Tobias ED - Meier, Hans ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte Sommersemester 2021 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand auf Initiative der Studierenden des 2020 neu gegründeten Masterstudiengangs „Elektro- und Informationstechnik (MEI)“, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Sommersemester 2021 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu präsentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel über noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verfügen, lag der wählbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen. T3 - Forschungsmethoden-Seminar - 2 KW - Elektrotechnik KW - Informationstechnik KW - Angewandte Wissenschaften KW - Literaturrecherche KW - Literature Review KW - Applied Sciences KW - Electrical engineering KW - Information technology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-21040 CY - Regensburg ER - TY - CHAP A1 - Swidergal, Krzysztof A1 - Wagner, Marcus A1 - Lubseder, C. A1 - von Wurmb, I. A1 - Meinhardt, Josef A1 - Marburg, Steffen T1 - Investigation of the forming tool dynamics by means of numerical simulation T2 - Advanced Metal Forming Processes in Automotive Industry, AutoMetForm 2016 N2 - In the forming tools for pressing car body parts, heavy blankholders are used to prevent buckling and wrinkling of the blank. During each press cycle, those large masses need to be lifted, raising thereby the structural dynamic load on the forming tool and on the press. Therefore a detailed knowledge about the forming tool dynamics is essential for an accurate and robust design of forming tools. In this paper, a dynamic finite element method (FEM) simulation of selected automotive forming tool is presented enabling identification of regions of critical stresses. For validation of the simulation results, the kinematic responses of the tool's components are compared with the measurements obtained in an experiment. KW - Finite-Elemente-Methode KW - Formgebungswerkzeug KW - Karosserieanbauteil KW - numerische Simulation KW - robuste Bauweise KW - simuliertes Ergebnis KW - Strukturdynamik Y1 - 2016 SP - 335 EP - 340 PB - Fraunhofer ER - TY - CHAP A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Marková, Jana A1 - Masciotta, Maria Giovanna ED - Baričević, Ana ED - Jelčić Rukavina, Marija ED - Damjanović, Domagoi ED - Guadagnini, Maurizio T1 - Optimizing in-situ testing for historic masonry structures: a case study BT - a case study T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) : Durability, Monitoring and Repair of Structures, 20-22 March 2019, Rovinj, Croatia Y1 - 2019 UR - http://toc.proceedings.com/50441webtoc.pdf SN - 978-1-5108-9296-5 SP - 684 EP - 691 PB - RILEM Publications ER - TY - CHAP A1 - Kaspar, Marcel A1 - Rabl, Hans-Peter A1 - Mayer, Wolfgang T1 - Differenzierte Kohlenwasserstoffanalytik im Dieselabgas bei verschiedenen Motorbetriebszustaenden : Detailed hydrocarbon analysis of diesel exhaust gas at different engine operating conditions T2 - 12. FAD-Konferenz „Herausforderung – Agbasnachbehandlung für Dieselmotoren“, 12, 2014, Dresden N2 - Beitrag und Praesentationsmaterial eines Vortrags ueber differenzierende Kohlenwasserstoffanalytik im Dieselabgas bei verschiedenen Motorbetriebszustaenden. Mit einem neu entwickelten, hochgenauen HC-Sensor werden unverbrannte HC im Abgas untersucht. Die differenzierende Untersuchung erfolgt an einem Massenspektrometer, das mit chemischer Ionisation arbeitet. Die Molekuele Ethin, Ethen und Propen wurden gezielt betrachtet. Es zeigt sich, dass bei kalten Betriebsbedingungen diese drei Komponenten etwa die Haelfte der gesamten HC Konzentration ergeben. Ein weiterer Punkt ist die Regeneration des Dieselpartikelfilters. KW - ABGASKONZENTRATION KW - ABGASTRENNUNG KW - ABGASZUSAMMENSETZUNG KW - DIESELMOTOR KW - EINSTUFENFILTER KW - GASFILTER KW - HAUPTSTROMFILTER KW - KATALYTISCHE ABGASNACHVERBRENNUNG KW - KATALYTISCHER REAKTOR KW - KOHLENWASSERSTOFF (ABGAS) KW - OXIDATIONSKATALYSATORANLAGE KW - Partikelfilter KW - PERIODISCH ZU REINIGENDER FILTER KW - R4-MOTOR KW - UEBERDRUCKFILTER Y1 - 2014 SP - 1 EP - 35 PB - Förderkreis Abgasnachbehandlungstechnologien für Verbrennungskraftmaschinen (FAD) e.V. CY - Dresden ER - TY - RPRT A1 - Bergmeier, Sonja A1 - Bock, Maximilian A1 - Fischer, Lukas A1 - Flassig, Nathanael A1 - Hidvégi, Barnabás A1 - Bächer, Tim A1 - Hierl, Jonas A1 - Kaltenbach, Dominik A1 - Lackermeier, Florian A1 - Laubmann, Julia A1 - Liebl, Jonas A1 - Pirthauer, Tobias A1 - Reif, Robin A1 - Roider, Stefan ED - Fuhrmann, Thomas ED - Hipp, Susanne ED - Niemetz, Michael ED - Sterz, Oliver T1 - FMS-Berichte Wintersemester 2024/25 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik T2 - FMS-Berichte Wintersemester 2024/25 N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2020/21 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 9 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-83121 VL - 2024 IS - 9 CY - Regensburg ER - TY - JOUR A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Achieving Optimal Reactive Power Compensation in Distribution Grids by Using Industrial Compensation Systems JF - Electricity N2 - This paper presents a method for integrating industrial consumers owning compensation systems as alternative reactive power sources into grid operating processes. In remuneration, they receive a market-based provision of reactive power. The aim is to analyze the potential of reactive power compensation systems of industrial companies connected to medium-voltage (10 kV–30 kV) AC grids in order to increase the reactive power ability of distribution grids. Measurement methods and reactive power potential results of six industrial companies are presented to characterize the amount and temporal availability of their reactive power potential. The presented approach for using the decentralized reactive power potential is a centralized reactive power control method and is based on optimal power flow (OPF) calculations. An optimization algorithm based on linear programming is used to coordinate a reactive power retrieval tuned to the actual demand. The influencing quantities are the current grid status (voltage and load flow capacity reserves at grid nodes and power lines) and the current reactive power potential of the reactive power sources. The compensation impact of six measured industrial companies on an exemplary medium-voltage grid is shown by an application example. KW - Blindleistung KW - Blindleistungsmanagement KW - Industriebetriebe KW - Optimal Power Flow KW - Reactive Power Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-59139 N1 - Corresponding author: Johannes Rauch VL - 4 IS - 1 SP - 78 EP - 95 PB - MDPI CY - Basel ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Control strategy for industrial reactive power sources depending on a specified reactive power setpoint value T2 - ETG Kongress 2023: Die Energiewende beschleunigen, 25.-26. Mai 2023, Kassel, Germany N2 - Industrial plants can provide reactive power (Q) for system- and grid-serving behavior, for which a functioning reactive power management system is essential. To make reactive power retrieval as efficient and safe as possible, the selection of reactive power sources to meet the Q-demand must consider their sensitivities and the restrictions of the industrial grid, such as operating equipment utilization or voltage limits. On this basis, a concept for a sensitivity-based control strategy that manages the reactive power retrieval of multiple reactive power sources depending on a predefined reactive power demand value is proposed. Based on the simulation of an industrial plant in the medium-voltage grid, which can provide reactive power in the form of industrial compensation systems (ICS) and generators, the operation of the algorithm is shown. Y1 - 2023 UR - https://ieeexplore.ieee.org/document/10173014/authors#authors SN - 978-3-8007-6108-1 SP - 553 EP - 558 PB - VDE VERLAG CY - Berlin ER - TY - JOUR A1 - Metsch, P. A1 - Schmidt, Henrik A1 - Sindersberger, Dirk A1 - Kalina, K. A. A1 - Brummund, J. A1 - Auernhammer, Günter A1 - Monkman, Gareth J. A1 - Kästner, Markus T1 - Field-Induced Interactions in Magneto-Active Elastomers BT - A Comparison of Experiments and Simulations JF - Smart Materials and Structures N2 - In this contribution, field-induced interactions of magnetizable particles embedded into a soft elastomer matrix are analyzed with regard to the resulting mechanical deformations. By comparing experiments for two-, three- and four-particle systems with the results of finite element simulations, a fully coupled continuum model for magneto-active elastomers is validated with the help of real data for the first time. The model under consideration permits the investigation of magneto-active elastomers with arbitrary particle distances, shapes and volume fractions as well as magnetic and mechanical properties of the individual constituents. It thus represents a basis for future studies on more complex, realistic systems. Our results show a very good agreement between experiments and numerical simulations—the deformation behavior of all systems is captured by the model qualitatively as well as quantitatively. Within a sensitivity analysis, the influence of the initial particle positions on the systems' response is examined. Furthermore, a comparison of the full three-dimensional model with the often used, simplified two-dimensional approach shows the typical overestimation of resulting interactions in magneto-active elastomers. Y1 - 2020 U6 - https://doi.org/10.1088/1361-665X/ab92dc N1 - Corrigendum: Field-induced interactions in magneto-active elastomers—a comparison of experiments and simulations (2020 Smart Mater. Struct. 29 085026); https://doi.org/10.1088/1361-665X/abb98b VL - 29 IS - 8 SP - 1 EP - 10 PB - IOPscience ER - TY - RPRT A1 - Caspar, Stefan A1 - Dorfner, Manuel A1 - Engelmann, Uwe A1 - Erhardsberger, Ludwig A1 - Gressitzek, Tobias A1 - Michelmann, Björn A1 - Steinberger, Melanie A1 - Stuchlý, Jan ED - Meier, Hans ED - Niemetz, Michael ED - Fuhrmann, Thomas ED - Reindl, Andrea T1 - FMS-Berichte Sommersemester 2023 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2020/21 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 6 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77787 IS - 1 CY - Regensburg ER - TY - JOUR A1 - Gärtner, Sebastian A1 - Rank, Daniel A1 - Heberl, Michael A1 - Gaderer, Matthias A1 - Dawoud, Belal A1 - Haumer, Anton A1 - Sterner, Michael T1 - Simulation and Techno-Economic Analysis of a Power-to-Hydrogen Process for Oxyfuel Glass Melting JF - Energies N2 - As an energy-intensive industry sector, the glass industry is strongly affected by the increasingly stringent climate protection targets. As established combustion-based production systems ensure high process stability and glass quality, an immediate switch to low greenhouse gas emission processes is difficult. To approach these challenges, this work investigates a step-by-step integration of a Power-to-Hydrogen concept into established oxyfuel glass melting processes using a simulation approach. This is complemented by a case study for economic analysis on a selected German glass industry site by simulating the power production of a nearby renewable energy park and subsequent optimization of the power-to-hydrogen plant performance and capacities. The results of this study indicate, that the proposed system can reduce specific carbon dioxide emissions by up to 60%, while increasing specific energy demand by a maximum of 25%. Investigations of the impact of altered combustion and furnace properties like adiabatic flame temperature (+25 °C), temperature efficiency (∆ξ = −0.003) and heat capacity flow ratio (∆zHL = −0.009) indicate that pure hydrogen-oxygen combustion has less impact on melting properties than assumed so far. Within the case study, high CO2 abatement costs of 295 €/t CO2-eq. were determined. This is mainly due to the insufficient performance of renewable energy sources. The correlations between process scaling and economic parameters presented in this study show promising potential for further economic optimization of the proposed energy system in the future. KW - Power-to-Gas KW - Hydrogen KW - Electrolysis KW - Oxyfuel KW - Glass Industry Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-22713 N1 - Corresponding author: Sebastian Gärtner VL - 14 IS - 24 PB - MDPI ER - TY - CHAP A1 - Grab, Robin A1 - Rauch, Johannes A1 - Götz, Rebekka A1 - Brückl, Oliver A1 - Eichner, Stefan A1 - Engel, Bernd T1 - Q-Dynamik: Blindleistungsstellgeschwindigkeiten im Verteilnetz T2 - Zukünftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021, Tagungsunterlagen N2 - Mit der Energiewende geht eine starke Dezentralisierung der Energieeinspeisung einher. So sind im Deutschland des Jahres 2020 rund 31.000 Windenergieanlagen (WEA) in Betrieb, während bei der Solarenergie vor kurzem die zweimillionste Photovoltaik-Anlage (PVA) installiert wurde. Fast alle diese dezentralen Energieressourcen (DER) sind nach den Einspeiserichtlinien der Vergangenheit und der Gegenwart in der Lage, Blindleistung bereitzustellen, um die Spannung im Netz zu regeln und zum Blindleistungsausgleich beizutragen. Weitere potentielle dezentrale Blindleistungsquellen wie Blockheizkraftwerke, Kompensationsanlagen und perspektivisch sogar Verbraucher und Speicher sind im Verteilnetz zu finden. Durch den stetigen Rückbau konventioneller Großkraftwerke, welche dem Übertragungsnetz bisher als Blindleistungsquellen zur Verfügung standen, bedarf es einer Untersuchung mit der Fragestellung, in welchem Maß die neue Erzeugungslandschaft auch in diesem Feld als Ersatz dienen kann. Ein mögliches Hindernis für einen breitangelegten Einsatz von DER zu Zwecken des spannungsebenenübergreifenden Blindleistungsmanagements ist mangelndes Wissen über die Regeldynamik dieser verteilten Blindleistungsquellen. Übertragungs- und Verteilnetzbetreiber, die DER aktiv für Blindleistungsausgleich oder statische Spannungsregelung einsetzen, geben in der Regel ihre Blindleistungsanforderungen in kleineren Stufen mit erheblichen Latenzzeiten zwischen zwei Schritten weiter. Befürchtet wird, dass schnellere Sprünge in der Blindleistungsvorgabe zu instabilen Betriebszuständen oder anderweitigen Fehlfunktionen im Netz führen können. Eine genauere Kenntnis der dynamischen Fähigkeiten vorhandener Blindleistungsquellen sowie der Auswirkungen auf die Netzstabilität und den Netzschutz könnte dazu beitragen, die Geschwindigkeit der Blindleistungsbereitstellung zu optimieren und somit temporäre Spannungsschwankungen und -verluste zu minimieren und die Spannungsstabilität insgesamt zu verbessern. Durch eine entsprechende Regelungs- und Einsatzstrategie kann ein optimales Zusammenspiel der verschiedenen Technologien zur Deckung der Blindleistungsbedarfe für unterschiedliche Zeitbereiche erzielt werden. Hierfür ist eine genaue Kenntnis der Blindleistungsstellgeschwindigkeiten und des dynamischen Regelverhaltens erforderlich. Dieser Beitrag stellt dazu Ergebnisse aus dem Forschungsprojekt „Q-Integral“ vor. Um die relevanten Zeitkonstanten der Blindleistungsbereitstellung vollständig aufzuführen, werden zunächst typische Kommunikationszeiten für die Übermittlung von Sollwerten diskutiert. Anschließend werden Untersuchungen zu theoretischen und praktischen Reaktionszeiten verschiedener Blindleistungsquellen vorgestellt. Dafür werden verschiedene Technologien wie Umrichter für PVA, Batteriespeicher und WEA sowie Synchrongeneratoren, die bei thermischen Kraftwerken die dominierende Technologie sind, betrachtet. Abschließend werden diese Werte mit realen Blindleistungsstellgeschwindigkeiten von ausgedehnten Wind- und Solarkraftwerken verglichen. KW - Blindleistung KW - Blindleistungsmanagement KW - Q-Dynamik KW - Blindleistungsquellen KW - Verteilungsnetz Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58762 SN - 978-3-948176-12-9 SP - 46 EP - 55 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Konzeptionierung netzplanerischer Prozessansätze zur Ermittlung von Blindleistungskapazitäten zum Ausgleich des Blindleistungsbedarfs in einer Netzregion T2 - Tagungsband Tagung Zukünftige Stromnetze 26./27. Januar 2022 (online) N2 - Um einen sicheren und zuverlässigen Stromnetzbetrieb zu gewährleisten, muss die Spannung im Grundfall als auch bei ungeplanten Ausfällen in definierten Bereichen gehalten werden. Im Übertragungsnetz wird hierfür bisher Blindleistung hauptsächlich aus Blindleistungskompensationsanlagen und konventionellen Großkraftwerken eingesetzt. Zukünftig wird nach §12h EnWG eine marktgestützte Beschaffung dieser Dienstleistung zur Spannungsregelung vorgeschrieben. Zugleich verändert sich der Blindleistungsbedarf der Netzbetriebsmittel durch die Integration erneuerbarer Energieanlagen und der Elektromobilität sowie durch den Netzausbau bei Übertragungs- und Verteilungsnetzbetreibern. Es bedarf somit angepasster Netzbetriebs- und Netzplanungskonzepte für ein technisch effizientes und wirtschaftlich günstiges Blindleistungsmanagement. Dieser Beitrag beschäftigt sich damit, Prozessansätze und Methodiken für ebendieses in der Netzplanung aufzuzeigen, um erforderliche Blindleistungskapazitäten unter minimalen Gesamtkostenaufwand und unter Berücksichtigung einer effizienten Blindleistungsbedarfsdeckung zu bestimmen. Dabei liegt der Fokus verstärkt in der Bedarfsanalyse. KW - Blindleistung KW - Blindleistungsmanagement KW - Netzplanungsprozesse KW - Spannungshaltung KW - Optimierungsverfahren Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58665 SN - 978-3-948176-16-7 SP - 117 EP - 126 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Analysis of the correlation behavior between local available information to the overall reactive power of a medium-voltage grid group T2 - Applied Research Conference - ARC 2017, 7 July 2017 München N2 - The initiated energy transition leads to extensive changes in the supply of energy. The increasing use of renewable energy causes a shift of the produced power from centralized conventional power plants to decentralized energy plants. Because of this redistribution and the related change of load-flows, new challenges and problems for distribution system operators appear. This includes the integration of new loads and plants into the existing power grid and the guarantee of a high supply security and quality. It also includes strengthened requirements for the use and provision of reactive power. The project “SyNErgie” (“Systemoptimierendes Netz- und Energiemanagement für Verteilungsnetze der Zukunft“) deals with the development of a new reactive power management, which gets embedded in grid planning and controlling processes. One focus of the project is on the integration of decentralized energy plants (DEPs) to the reactive power management. The aim is to develop a decentralized and self-sufficient reactive power control system, which only works with local available information (measures). Therefore is no necessity of a complex communication system to the grid control center. Self-controlled Q-controller in the DEPs get characteristic curves and control the reactive power sources with local measurements (e.g. current, voltage, effective power). This new reactive power control management aims for the reactive power compensation in order to increase the integration capacity of loads and plants in a grid [2]. In order to generate characteristic curves for DEPs, it is necessary to analyze the correlation behavior between the local available measurements at the DEPs and the overall-Q-behavior of the grid group at the transformer. In that regard, influencing quantities should be considered. The aim is to involve und evaluate all relevant influencing quantities in order to determine energy plants and certain operating points, in which the correlation behavior and the prediction for the overall-Q-behavior are sufficient. The next step is to develop a model that fits these correlation behaviors and generate characteristic curves. One method to generate characteristic curves for the Q-controllers is regression analysis. The developed Q-control-system with the characteristic curves will be tested, evaluated and optimized in a following field test in cooperation with distribution system operators. KW - Mittelspannungsnetz KW - Blindleistungsmanagement KW - Blindleistung KW - Integration Erneuerbare Energien KW - Potentialerschließung Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58712 SP - 224 EP - 230 CY - München ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Entwicklung eines Regelkonzeptes für einen optimierten Blindleistungsabruf auf Basis von Blindleistungspotentialanalysen bei Industriebetrieben im Mittelspannungsnetz T2 - Tagungsband Tagung Zukünftige Stromnetze 26./27. Januar 2022 (online) N2 - Im Zuge der Energiewende ergibt sich ein Wandel in der Struktur des Elektrizitätsversorgungsnetzes. Die Verschiebung der Erzeugungsleistung von konventionellen Großkraftwerken in höheren Netzebenen hin zu dezentralen erneuerbaren Energieanlagen in niedrigeren Netzebenen resultiert sowohl in bidirektionalen Lastflüssen als auch in schwankenden Einspeisecharakteristiken. Des Weiteren folgen durch den Wegfall von Großkraftwerken als Blindleistungsquellen Leistungsdefizite in der Übertragungsnetzebene, die kompensiert werden müssen. Daraus resultieren Herausforderungen an einen sicheren und zuverlässigen Betrieb der Verteil- und Übertragungsnetze. Neue Konzepte müssen für die Erbringung von Blindleistung entwickelt werden, es soll mehr Blindleistung aus dem Verteilungsnetz zur Verfügung gestellt werden, um die Systemstabilität zu wahren. Im Rahmen des Projektes Q-Integral wird das Thema „Blindleistung“ (Q) ganzheitlich untersucht. Es werden dazu verschiedene Erbringungsoptionen für Blindleistung hinsichtlich technischer und wirtschaftlicher Potentiale untersucht, die in ein funktionales und effizientes Blindleistungsmanagement eingebracht werden. Die Untersuchungsansätze dafür sind sowohl spannungsebenen-übergreifend als auch netzbetreiber-übergreifend. Ein Ansatzpunkt des Projektes ist die Betrachtung der Blindleistungsbereitstellung von Industriebetrieben. Dazu wird das Potential von Betrieben, die an das Verteilnetz angeschlossen sind und Blindleistung durch Kompensations- oder Erzeugungsanlagen bereitstellen können, untersucht. Ziel ist es, das gesicherte und maximale induktive sowie kapazitive Potential zu bestimmen. Das gesicherte kapazitive Potential kann genutzt werden, um Aussagen darüber zu treffen, wie stark dem Spannungsfall im vorgelagerten Netz zu Starklastzeiten entgegengewirkt werden kann. Anhand des gesicherten induktiven Potentials kann ein Spannungsanstieg während Schwachlastzeiten ausgeglichen werden kann. In diesem Beitrag werden Ergebnisse aus dem Projekt Q-Integral vorgestellt. Dazu werden zuerst die Berechnungsgrundlagen der induktiven und kapazitiven Blindleistungspotentiale aufgezeigt und die Ergebnisse der Berechnungen vorgestellt. Die gewonnen Ergebnisse entstammen aus Messungen an einem Industriebetrieb mit Blindleistungskompensationsanlagen (BKA), den entsprechenden Reglern der Anlagen und einer installierten Kompensationsleistung von 1600 kvar. Sowohl die Lastgänge als auch das Schaltverhalten der einzelnen Kompensationsanlagen liegen den Berechnungen zugrunde. Um den Austausch der Blindleistung an der Übergabestelle des Betriebs zum Mittelspannungsnetz netzdienlich einzustellen, bedarf es eines geeigneten Regelkonzepts, das neben den BKAs auch weitere Q-Quellen berücksichtigt. Deshalb wird abschließend ein Regelkonzept vorgestellt, das den technisch-optimierten Blindleistungsabruf unter Berücksichtigung mehrerer Blindleistungsquellen behandelt. KW - Blindleistung KW - Blindleistungsmanagement KW - Blindleistungsquellen KW - Blindleistungspotentiale KW - Industriebetriebe Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58704 SN - 978-3-948176-16-7 SP - 224 EP - 233 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver A1 - Engel, Bernd ED - Schulz, Detlef T1 - Analysis and optimization of the steady state voltage deviation demand for reactive power planning using installed reactive power sources T2 - NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg N2 - The provision of reactive power is one option for maintaining the grid voltage, that is defined as an ancillary service in Germany. This paper presents an approach for determining deficient voltage deviation demands within an electrical grid for long term reactive power planning investigations. In contrast to previous approaches, which evaluate the Q-behavior of extended ward elements or grid assets, voltage deviations are analyzed bus-specifically. So further reactive power planning investigations are able to scale and optimize additional reactive power sources directly on planning voltage limits using load flow sensitivity techniques. The focus lies on the analysis of the steady state demand at base case conditions. Therefore, a grid planning process is conceptualized. An optimal power flow algorithm based on Differential Evolution is used for an optimal reactive power dispatch of installed reactive power sources, e. g. reactive power compensation systems or (renewable) energy sources to minimize the total voltage deviation according to voltage limits of Transmission System Operators planning principles. Methodological and processuals specifications as well as an application use case with an exemplary transmission system are presented in this paper. KW - Reactive Power KW - Reactiver Power Planning KW - Voltage Control KW - Optimal Power Flow KW - Differential Evolution Y1 - 2022 UR - https://ieeexplore.ieee.org/document/10048083 SN - 978-3-8007-5983-5 SN - 2510-6902 SP - 175 EP - 182 PB - VDE-Verlag CY - Berlin ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver ED - Schulz, Detlef T1 - Long-term analysis of industrial reactive power potentials with consideration of plant-internal grid restrictions using the example of an industrial plant in a distribution grid T2 - NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg N2 - Since conventional generation plants provide a considerable share of reactive power but are gradually being shut down due to energy transition, leading to power deficits at the transmission grid level, new concepts for the supply of reactive power must be developed. As one possibility for the latter, industrial plants in the distribution grid are considered suitable, as their reactive power potentials can contribute to voltage maintenance and thus to a grid- or system-serving behavior. In this paper, the determination of reactive power potentials provided by industrial compensation systems (ICS) is presented. An industrial plant in the medium voltage grid, with three installed ICSs, is investigated. The potentials are determined and described based on their time characteristics, which provide information about the occurrence and distribution of inductive and capacitive potentials. A grid simulation of the investigated industrial grid is used to analyze the effects of retrieving the reactive power potentials regarding equipment utilizations and voltage limits. KW - Reactive Power KW - Reactive Power Potentials KW - Industrial plant KW - Voltage Stability KW - Long term analysis Y1 - 2022 UR - https://ieeexplore.ieee.org/document/10048065 SN - 978-3-8007-5983-5 SN - 2510-6902 SP - 51 EP - 56 PB - VDE-Verlag CY - Berlin ER - TY - RPRT A1 - Brixner, Luis A1 - Gnerlich, Patrick A1 - Jakob, Jonas A1 - Kiener, Johannes A1 - Oberländer, Jonas A1 - Plößl, Moritz A1 - Schächinger, Stefan A1 - Stelz, Raphael A1 - Wartner, Felix ED - Fuhrmann, Thomas ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte Wintersemester 2023/24 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2020/21 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 7 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77796 IS - 1 CY - Regensburg ER - TY - RPRT A1 - Blößer, Julia A1 - Branilovic, Fabio A1 - Michael, Bretz A1 - Ebner, Andreas A1 - Gleich, Ralf A1 - Inderst, Christian A1 - Kopp, Lorenz A1 - Müller, Markus A1 - Schächiner, Michael A1 - von Beerfelde, Rebekka ED - Fuhrmann, Thomas ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte Sommersemester 2024 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik T2 - FMS-Berichte Sommersemester 2024 N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2020/21 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 8 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77801 IS - 1 CY - Regensburg ER - TY - RPRT A1 - Rank, Daniel A1 - Heberl, Michael A1 - Sterner, Michael T1 - Die CO2-Bilanz der OTH [Ostbayerischen Technische Hochschule Regenburg] BT - Tool für Hochschulen und Firmen Y1 - 2020 UR - https://sae58cb7e2208a3d2.jimcontent.com/download/version/1613400473/module/9240277976/name/1. Sitzung AG_Präsentation Prof. Sterner-1.pdf ER - TY - JOUR A1 - Chatzitakis, Paris A1 - Safarov, Javid A1 - Opferkuch, Frank A1 - Dawoud, Belal T1 - Experimental investigation of an absorption heat pump with organic working pairs JF - Applied Thermal Engineering N2 - As part of a systematic approach towards the search for alternative absorption heat pump (AHP) working pairs that could potentially provide comparable performance to conventional ones, a previous work performed a detailed theoretical cycle analysis and simulation that revealed concrete correlations between key working fluid thermophysical properties and AHP performance indicators. Following this work, targeted combinations of two organic refrigerants, 2,2,2-trifluoroethanol (TFE) and 2,2,3,3,3-pentafluoropropanol (5FP) and two organic absorbents, 1,3-dimethyl-2-imidazolidinone (DMI) and 2-pyrrolidone (PYR) were tested in a prototype 5 kW AHP, based on a highly compact plate heat exchanger design, which has been previously introduced. The purpose of this effort was to test the findings of the previous work with experimental measurements. The working pair combinations were also subjected to vapor liquid equilibrium (VLE) and viscosity measurements, in order to determine reliable activity coefficient and improve the accuracy of the simulations. The experimental performance data agree well with the COP simulations and show to be consistent with the conclusions derived from the previous theoretical work. KW - Absorption heat pump KW - Coefficient of performance KW - FLUID KW - MIXTURES KW - Organic working pairs KW - Specific solution circulation Y1 - 2019 U6 - https://doi.org/10.1016/j.applthermaleng.2019.114311 VL - 163 IS - December PB - Elsevier ER - TY - JOUR A1 - Hansen, B. A1 - Hoebler, Michael A1 - Purr, Stephan A1 - Meinhardt, J. A1 - Merklein, Marion T1 - Basics for inline measurement of tribological conditions in series production of car body parts JF - IOP Conference Series: Materials Science and Engineering N2 - The quality of car body parts in series production is strongly dependent on the tribological behavior. Fluctuating material properties such as the sheet roughness and the amount of lubricant have an influence on the forming process. On the basis of large amounts of data it is possible to investigate the friction behavior in series production and to make process adjustments if required. Therefore, inline measurement systems have a great potential to detect the sheet roughness during the cutting process of blanks in the coil line. Furthermore, contactless systems are advantageous as they do not damage the surface. Nevertheless, the optical measuring is influenced by the lubricant layer on top of the surface. Therefore, the previously unknown impact of the lubricant on the measuring result is investigated. Within this study, stationary optical roughness measurements have been conducted using different amounts of lubricant on hot-dip galvanized EDT steel. The results demonstrate the influence of different amounts of lubricant on the sheet roughness measurement. Hence, it is possible to correct the inline measuring results and gain knowledge of fluctuating surface roughness. In addition, strip drawing test has been carried out to investigate the effect of fluctuating tribological conditions. Y1 - 2019 U6 - https://doi.org/10.1088/1757-899x/651/1/012050 VL - 651 PB - IOP Publishing ER - TY - CHAP A1 - Bresinsky, Markus A1 - Reusner, Florian T1 - GLOBE – Learn and Innovate Digitization by a Virtual Collaboration Exercise and Living Lab T2 - Interactivity, Game Creation, Design, Learning, and Innovation. 6th International Conference, ArtsIT 2017, and Second International Conference, DLI 2017, Heraklion, Crete, Greece, October 30–31, 2017, Proceedings N2 - This paper presents an advanced interactive learning platform .dot that implements the GLOBE exercise, using innovative information and communication technologies to enhance learning and development of management and leadership skills in a complex organizational setting. GLOBE on the one hand focuses on competences around ICT and virtual collaboration, and on the other hand on digital transformation, technologies and tools at higher education institutions. By this applied science, learning and developing on the real-world platform, analysis and drive of digital innovation and transformation can be fostered. The main goal is to co-create knowledge and solutions in the following focused subjects: Management and leadership of multidisciplinary, multinational and multicultural virtual and real collaboration in a complex organizational environment. GLOBE uses real world scenarios (e.g. United Nations mission) and involves real world actors. This comprehensive educational approach should enhance learning techniques and leverage learning progress with hands-on experiences and applied science in the context of ICT and virtual collaboration, and the embodied dynamics of behavior to support innovation and development. KW - Digitization KW - Experiential learning KW - Human factors KW - ICT KW - Interactive and collaborative learning KW - Living Lab KW - Open innovation KW - Problem-based learning KW - Virtual collaboration Y1 - 2018 U6 - https://doi.org/10.1007/978-3-319-76908-0_26 SP - 273 EP - 281 PB - Springer Nature ER - TY - JOUR A1 - Hofrichter, Andreas A1 - Rank, Daniel A1 - Heberl, Michael A1 - Sterner, Michael T1 - Determination of the optimal power ratio between electrolysis and renewable energy to investigate the effects on the hydrogen production costs JF - International Journal of Hydrogen Energy N2 - Green hydrogen via renewable powered electrolysis has a high relevance in decarbonization and supply security. Achieving economically competitive hydrogen production costs is a major challenge in times of an energy price crisis. Our objective is to show the economically optimal installed capacity of electrolysers in relation to wind and solar power so swift and credible statements can be made regarding the system design. The ratio between renewable generation and electrolysis power as well as scaling effects, operating behaviour and development of costs are considered. Hydrogen production costs are calculated for four exemplary real PV and wind sites and different ratios of electrolysis to renewable power for the year 2020. The ideal ratio for PV systems is between 14% and 73% and for wind between 3.3% and 143% for low and high full load hours. The lowest hydrogen production costs are identified at 2.53 €/kg for 50 MW wind power and 72 MW electrolysis power. The results provide plant constructors the possibility to create a cost-optimized design via an optimum ratio of electrolysis to renewable capacity. Therefore, the procedures for planning and dimensioning of selected systems can be drastically simplified. Y1 - 2023 U6 - https://doi.org/10.1016/j.ijhydene.2022.09.263 SN - 0360-3199 N1 - Corresponding author: Michael Heberl N1 - Corrigendum to “Determination of the optimal power ratio between electrolysis and renewable energy to investigate the effects on the hydrogen production costs” [Int J Hydrogen Energy 48 (5) (2023) 1651–1663] - https://doi.org/10.1016/j.ijhydene.2023.03.128 VL - 48 IS - 5 SP - 1651 EP - 1663 PB - Elsevier ER - TY - CHAP A1 - Gärtner, Sebastian A1 - Rank, Daniel A1 - Heberl, Michael A1 - Gaderer, Matthias A1 - Sterner, Michael T1 - Integration of Power-To-Methane into Glass Melting Processes T2 - Proceedings of the International Renewable Energy Storage Conference (IRES 2022) N2 - The glass industry is facing increased challenges regarding climate protection targets and rising energy costs. The integration of renewable energy including conversion and storage is a key for both challenges in this energy-intensive industrial sector, which has been mainly relying on fossil gas so far. The options considered to this point for reducing CO2 emissions and switching to a renewable energy supply involve far-reaching changes of the established melting processes. This entails significant risks in terms of influences on glass quality and stable production volumes. The presented approach for the integration of a Power-to-Methane (PtM) system into the glass industry is a completely new concept and has not been considered in detail before. It allows the use of established oxyfuel melting processes, the integration of fluctuating renewable energy sources and a simultaneous reduction of CO2 emissions by more than 78%. At the same time, natural gas purchases become obsolete. A techno-economic evaluation of the complete PtM process shows, that 1,76 €/m3 or 1,26 €/kg synthetic natural gas are possible with renewable energy supply. Using electricity from the energy grid would require electricity prices < 0,126 €/kWh to allow cost competitive PtM processes in the glass industry. Such electricity prices could be achieved by electricity market-based optimization and operation of the PtM system. This operation strategy would require AI-based algorithms predicting availabilities and prices on future-based markets. KW - Power-to-Gas KW - Methanation KW - Glass Melting KW - Glass Industry KW - Decarbonisation Y1 - 2023 U6 - https://doi.org/10.2991/978-94-6463-156-2_12 SN - 2589-4943 VL - 16 SP - 147 EP - 161 PB - Atlantis Press ER - TY - CHAP A1 - Tremmel, Florian A1 - Nagler, Oliver A1 - Kutter, Christoph A1 - Holmer, Rainer T1 - Smart Cantilever Probe with Integrated Force and Acoustic Emission Sensor T2 - 2023 IEEE SENSORS, Vienna, Austria, 10/29/2023 - 11/1/2023 N2 - Acoustic emission (AE) testing recently found its application in the wafer testing sector of the semiconductor industry. To find out the mechanical robustness of semiconductor devices, contact pads on the chip surface are intentionally overstressed with an indenter tip and the appearing oxide cracks are detected with help of the generated AE signals. This is done in a customized test bench with a patented sensor-indenter system. This paper presents an improved version of the measurement setup that solves certain disadvantages of it and can be used in a standard wafer prober. The main components of the developed sensor system are a strain gauge for contact force measurement and a piezoelectric sensor element for AE signal detection. Both components are integrated on a cantilever beam which has an exchangeable indenter tip at its free end. The cantilever probe is electrically conductive to enable electrical tests via the indenter tip. This smart sensor-cantilever combination (SCC) can be mounted with several adapter components on a carrier plate to place it in a wafer prober. For both sensor elements amplifier circuits are developed to enhance their signal-to-noise ratios (SNRs). A prototype setup is shown together with simulated and experimental results to demonstrate its performance. The mechanical properties of the cantilever, as well as the force sensor and the AE crack signals, already fulfill the requirements for an implementation in a wafer prober. To further improve the sensor resolutions and detection limits, several optimizations regarding the design of the SCC are in progress. KW - Acoustic emission testing KW - piezoelectric sensor KW - strain gauge KW - operational amplifier circuit Y1 - 2023 SN - 979-8-3503-0387-2 U6 - https://doi.org/10.1109/SENSORS56945.2023.10325021 SP - 1 EP - 4 PB - IEEE ER - TY - INPR A1 - Heberl, Michael A1 - Withelm, Christian A1 - Kaul, Anja A1 - Rank, Daniel A1 - Sterner, Michael T1 - Prospective Life Cycle Assessment of Biological Methanation in a Trickle-Bed Pilot Plant and a Potential Scale-Up N2 - In this study, a pilot-scale trickle-bed reactor for biological methanation and various scale-up scenarios for 2023 and 2050 were investigated using LCA. A best- and worst-case scenario for technology development until 2050 was evolved using cross consistency analysis and morphological field, based on which the data for the ecological models were determined.The results show that the plant scale-up has a very positive effect on the ecological consequences of methanation. In the best-case scenario, the values are a factor of 23-780 lower than those of the actual plant today. A hot-spot analysis showed that especially electrolysis operation has a large impact on total emissions. The final Monte-Carlo simulation shows that the technology is likely to achieve a low GWP with a median of 104.0 kg CO2-eq / MWh CH4. Y1 - 2023 U6 - https://doi.org/10.2139/ssrn.4635066 N1 - Der Aufsatz wurde peer-reviewd veröffentlich und ist ebenfalls in diesem Repositorium verzeichnet unter: https://opus4.kobv.de/opus4-oth-regensburg/frontdoor/index/index/docId/7349 PB - SSRN ER - TY - CHAP A1 - Rill, Georg ED - Apetaur, Milan T1 - Vehicle Dynamics in Real-Time Simulation T2 - The dynamics of vehicles on roads and on tracks N2 - This paper presents some ideas on a new concept, named COMPACT (Computer Simulation of Passenger Cars and Trucks). COMPACT was developed for the mathematical description of vehicles in all driving situations. As COMPACT is completely adopted to the particular problems in road vehicle dynamics, it results in a computer code where execution time is minimized. Thus, even real-time application at the Daimler-Benz driving simulator is possible. Previous Chapter Next Chapter Y1 - 2021 SN - 9781003210894 U6 - https://doi.org/10.1201/9781003210894-40 SP - 337 EP - 347 PB - CRC Press CY - Boca Raton ER - TY - INPR A1 - Meisinger, Alexander A1 - Hofrichter, Andreas A1 - Bauer, Franz A1 - Sterner, Michael T1 - Unlocking Potential Energy Partnerships in Europe: a Case Study on the Way to a Franco-German Energy Transition N2 - Global warming is already causing global destabilization. Geopolitical challenges fuel this instability and highlight the need for trusted energy partnerships to ensure energy security. To limit global warming and increase energy security, it is essential to take joint action on an international and global scale. The European Green Deal contributes to this. However, specific national actions are still needed. This research presents a way forward for a Franco-German energy transition and unlocks the potential of energy partnerships within Europe, using a cost-based, sector-coupled optimization model. Both countries are coupled via an isolated country optimization approach. Thus, the focus is on the development of each national energy system. The results highlight the increase of energy security in line with the European Green Deal. The main pillars of the energy transition are solar energy (32- 33%), wind energy (25-38%) and biogenic energy sources (13-27%). Nuclear power is being phased out in Germany and France. The results show that a Franco-German energy partnership has great potential. Overall, France can cost-effectively cover 25% of Germany’s hydrogen import needs (122 TWh) in 2050. At the same time, France can also benefit from the energy partnership in terms of economic growth and joint action to mitigate climate crisis. KW - Decarbonization KW - Energy partnership KW - Energy system modelling KW - Energy transition KW - European Green Deal KW - Power-to-X Y1 - 2025 U6 - https://doi.org/10.2139/ssrn.5251699 PB - SSRN ER - TY - JOUR A1 - Romeis, Dirk A1 - Kostrov, Sergei A. A1 - Kramarenko, Elena Yu A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail A1 - Saphiannikova, Marina T1 - Magnetic-field-induced stress in confined magnetoactive elastomers JF - Soft Matter N2 - We present a theoretical approach for calculating the state of stress induced by a uniform magnetic field in confined magnetoactive elastomers of arbitrary shape. The theory explicitly includes the magnetic field generated by magnetizable spherical inclusions in the sample interior assuming a non-linear magnetization behavior. The initial spatial distribution of particles and its change in an external magnetic field are considered. This is achieved by the introduction of an effective demagnetizing factor where both the sample shape and the material microstructure are taken into account. Theoretical predictions are fitted to the stress data measured using a specifically designed experimental setup. It is shown that the theory enables the quantification of the effect of material microstructure upon introducing a specific microstructural factor and its derivative with respect to the extensional strain in the undeformed state. The experimentally observed differences between isotropic and anisotropic samples, compliant and stiff elastomer matrices are explained. Y1 - 2020 U6 - https://doi.org/10.1039/D0SM01337D VL - 16 IS - 39 SP - 9047 EP - 9058 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Yuskevich, Pavel A1 - Savelev, Dmitrii V. A1 - Belyaeva, Inna A. T1 - Induced anisotropy in composite materials with reconfigurable microstructure: Effective medium model with movable percolation threshold JF - Physica A: Statistical Mechanics and its Applications N2 - In composite materials, with field-dependent restructuring of the filler material (changes in the mutual arrangement of inclusions), the presence of an external magnetic field induces anisotropy of the dielectric properties, even if the composite is isotropic in the absence of an external field. A modified effective medium approximation is proposed for the calculation of the components of effective permittivity within a class of composites with reconfigurable microstructure, where both phases (the filler and the matrix) are isotropic and the inclusions have spherical shape. The effective physical properties are calculated in the parallel and perpendicular directions to an applied field. The appearance of the anisotropy of the permittivity is simulated by the introduction of two not-equal, possibly variable (field-dependent) percolation thresholds. The implications, of the proposed theoretical approach, are demonstrated for the case of the dielectric properties of magnetoactive elastomers (MAEs). In MAEs with soft polymer matrices, the mutual arrangement of micrometer-sized magnetic inclusions can significantly change in an applied magnetic field. A reasonable agreement between theory and experiment at a measurement frequency of 1 kHz is found, and is improved in comparison to the previous models. The components of the effective permittivity tensor, characterizing the dielectric properties along the direction of the applied magnetic field and in the orthogonal direction, grow with an increasing field. This growth is more pronounced for the permittivity component in the field direction. The possible extensions of the theoretical model and future directions of research are discussed. The presented theoretical approach can be useful for the application-driven development of a number of smart materials, in particular electro- and magnetorheological gels, elastomers and fluids. KW - Effective medium theory KW - Magnetoactive elastomer KW - Percolation threshold KW - Anisotropy KW - Effective permittivity KW - Random heterogeneous medium Y1 - 2020 U6 - https://doi.org/10.1016/j.physa.2020.125170 VL - 560 IS - December PB - Elsevier ER - TY - JOUR A1 - Savelev, Dmitrii V. A1 - Belyaeva, Inna A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Romeis, Dirk A1 - Kettl, Wolfgang A1 - Kramarenko, Elena Yu A1 - Saphiannikova, Marina A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail T1 - Giant extensional strain of magnetoactive elastomeric cylinders in uniform magnetic fields JF - Materials N2 - Elongations of magnetoactive elastomers (MAEs) under ascending–descending uniform magnetic fields were studied experimentally using a laboratory apparatus specifically designed to measure large extensional strains (up to 20%) in compliant MAEs. In the literature, such a phenomenon is usually denoted as giant magnetostriction. The synthesized cylindrical MAE samples were based on polydimethylsiloxane matrices filled with micrometer-sized particles of carbonyl iron. The impact of both the macroscopic shape factor of the samples and their magneto-mechanical characteristics were evaluated. For this purpose, the aspect ratio of the MAE cylindrical samples, the concentration of magnetic particles in MAEs and the effective shear modulus were systematically varied. It was shown that the magnetically induced elongation of MAE cylinders in the maximum magnetic field of about 400 kA/m, applied along the cylinder axis, grew with the increasing aspect ratio. The effect of the sample composition is discussed in terms of magnetic filler rearrangements in magnetic fields and the observed experimental tendencies are rationalized by simple theoretical estimates. The obtained results can be used for the design of new smart materials with magnetic-field-controlled deformation properties, e.g., for soft robotics. KW - magnetostriction KW - magnetoactive elastomer KW - extensional strain KW - hysteresis KW - magnetomechanical effect KW - magnetodeformation Y1 - 2020 U6 - https://doi.org/10.3390/ma13153297 SN - 1996-1944 N1 - Corresponding author: Mikhail Shamonin VL - 13 IS - 15 SP - 1 EP - 17 PB - MDPI CY - Basel ER - TY - JOUR A1 - Savelev, Dmitrii V. A1 - Fetisov, Leonid Y. A1 - Chashin, Dmitri V. A1 - Fetisov, Yuri K. A1 - Khon, Anastasia A1 - Shamonin (Chamonine), Mikhail T1 - Effects of ferromagnetic-material thickness on magnetoelectric voltage transformation in a multiferroic heterostructure JF - Smart Materials and Structures N2 - A magnetoelectric (ME) voltage transformer is fabricated on the basis of a ferromagnetic (FM)-piezoelectric (PE) heterostructure comprising two equally thick laminated layers of an amorphous FM alloy and a piezoceramic lead zirconate-titanate layer sandwiched between them. The structure, placed inside an excitation coil, is electrically poled and magnetized in the direction of the long axis. The primary voltage is applied to the coil and the secondary voltage is measured between the electrodes of the PE material. It is shown for the first time that the change in the total thickness of magnetic layers significantly influences the transformer ' s characteristics. At the largest total thickness of FM layers of 138 mu m, the open-circuit voltage transformation ratio K has a maximum value of about 20, and the power transfer efficiency eta at a matched resistive load of about 20 k omega reaches 45%. The variation of the control magnetic field in the range of 0-21.6 kA m(-1) makes it possible to change the voltage transformation ratio K from zero to the maximum value. A simple model allows one to calculate the dependence of the characteristics of the ME transformer on the frequency of the primary voltage, thickness of the FM layers, control magnetic field, and the load. KW - magnetoelectric effect KW - magnetostriction KW - multiferroic heterostructure KW - piezoelectric effect KW - voltage transformer Y1 - 2021 U6 - https://doi.org/10.1088/1361-665X/abf6c0 VL - 30 IS - 6 PB - IOP PUBLISHING ER - TY - JOUR A1 - Savelev, Dmitrii V. A1 - Belyaeva, Inna A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Large Wiedemann effect in a magnetoactive elastomer JF - Journal of Magnetism and Magnetic Materials N2 - Large twists of a soft tube (hollow cylinder) in helical magnetic fields are presented for the first time. Such a phenomenon is usually denoted as the Wiedemann effect. The tube is fabricated from a soft magnetoactive elastomer material with the shear modulus of about 56 kPa. The composite material comprises 80 mass% of micrometer-sized iron particles embedded into a polydimethylsiloxane matrix. The circular magnetic field is generated by an electric current in a straight wire passing through the inner hole of the tube. The maximum value of approximately 350″/cm is observed in a longitudinal magnetic field of a few kA/m overlapped with a circumferential magnetic field of about 1.4 kA/m on the surface of the inner hole. A pronounced hysteresis in the dependence of the Wiedemann effect on the circular magnetic field is found. The ways to enhance the Wiedemann twist in magnetoactive elastomers are discussed. The observed large effect is promising for application in magnetic-field controlled torsional actuators, in particular for soft robotics. Y1 - 2020 U6 - https://doi.org/10.1016/j.jmmm.2020.166969 VL - 511 IS - October PB - Elsevier ER - TY - JOUR A1 - Savelev, Dmitrii V. A1 - Fetisov, Leonid Y. A1 - Chashin, Dmitri V. A1 - Shabin, P. A. A1 - Vyunik, D. A. A1 - Fedulov, Feodor A1 - Kettl, Wolfgang A1 - Shamonin (Chamonine), Mikhail T1 - Method of Measuring Deformations of Magnetoactive Elastomers under the Action of Magnetic Fields JF - Russian Technological Journal Y1 - 2019 U6 - https://doi.org/10.32362/2500-316x-2019-7-4-81-91 VL - 7 IS - 4 SP - 81 EP - 91 ER - TY - CHAP A1 - Mühlbauer, Christian A1 - Rabl, Hans-Peter A1 - Rottengruber, Hermann ED - Siebenpfeiffer, Wolfgang T1 - Development of a Methodology for Acoustic Analysis and Optimization of Mechatronic Fuel Injection Systems T2 - Automotive Acoustics Conference 2019: Proceedings, 5. Internationale ATZ-Fachtagung Fahrzeugakustik N2 - To identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed that simulates the structure and airborne noise emission. The setup of the system test bench includes an assembly of the acoustical relevant engine parts and an encapsulated drive for the high-pressure pump. A specific control unit enables a high variability for the operation strategy of the injection system. The focus of this study is on the development of a methodology to analyze and optimize the sound quality of gasoline direct injectors in critical operation points by suitable active means. For this, the injection parameters in engine idle have been identified and subsequently transferred to the system test bench. Additionally, the injection parameters have been optimized acoustically and the impacts on the key functions regarding injection rating and shot-to-shot scattering of the injected fuel mass are discussed. Y1 - 2020 SN - 978-3-658-27668-3 U6 - https://doi.org/10.1007/978-3-658-27669-0_15 SP - 211 EP - 225 PB - Springer Vieweg CY - Wiesbaden ER - TY - GEN A1 - Pershina, K. V. A1 - Savelev, Dmitrii V. A1 - Glavan, Gašper A1 - Chashin, Dmitri V. A1 - Belyaeva, Inna A. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - The voltage response of a structure comprising a magnetoactive-elastomer cylinder and a piezoelectric material to magnetic field step excitations T2 - The 4th International Baltic Conference on Magnetism (IBCM 2021) : Svetlogorsk, Russia August 29 - September 2, 2021 : Book of Abstracts Y1 - 2021 UR - http://smba.science/wp-content/uploads/2021/10/IBCM-2021-Book-of-Abstracts-5.pdf SP - 182 PB - Immanuel Kant Baltic Federal University, Kaliningrad, Russia ER - TY - BOOK A1 - Rill, Georg A1 - Schaeffer, Thomas T1 - Grundlagen und Methodik der Mehrkörpersimulation N2 - Dieses Lehrbuch stellt die Methoden der Mehrkörpersimulation anschaulich dar und erläutert an einfachen Beispielen die Vor- und Nachteile bei der praktischen Anwendung. In den Text integrierte Matlab-Skripte und -Funktionen verdeutlichen die einzelnen Methoden. Die Modellbildung, die mathematische Beschreibung und die numerische Simulation von Systemen starrer Körper bilden dabei die Schwerpunkte. Konkrete Beispiele beinhalten die Eigendynamik eines Traktors mit Vorderachsfederung, das Hubschrauberrotorblatt sowie eine Pkw- Vorderachse. Die entsprechenden Matlab-Skripte und Lösungen zu den Übungsaufgaben können auf der Springer-Homepage beim Buch heruntergeladen werden. Neu aufgenommen wurden SparseMatrix Operationen sowie ein Beispiel zu einfach geschlossenen kinematischen Schleifen. Y1 - 2017 SN - 978-3-658-16008-1 U6 - https://doi.org/10.1007/978-3-658-16009-8 PB - Springer CY - Wiesbaden ET - 3. Aufl. ER - TY - BOOK A1 - Rill, Georg A1 - Schaeffer, Thomas T1 - Grundlagen und Methodik der Mehrkörpersimulation : Vertieft in Matlab-Beispielen, Übungen und Anwendungen N2 - Dieses Lehrbuch vermittelt nicht nur Grundlagen, sondern stellt auch die Methoden der Mehrkörpersimulation anschaulich dar und erläutert an einfachen Beispielen die Vor- und Nachteile bei der praktischen Anwendung. In den Text integrierte Matlab-Skripte und -Funktionen verdeutlichen die einzelnen Methoden und ermöglichen es, Aufwand und Problematik bei der Umsetzung der Theorie innerhalb von Simulationsprogrammen einzuschätzen. Die Modellbildung, die mathematische Beschreibung und die numerische Simulation von Systemen starrer Körper bilden dabei die Schwerpunkte. Konkret behandelte Beispiele sind die Eigendynamik eines Traktors mit gefederter Vorderachse, das Rotorblatt eines Hubschraubers sowie die Vorderachse eines Pkws. Die entsprechenden Matlab-Skripte und Lösungen zu den Übungsaufgaben können auf der Springer-Homepage beim Buch heruntergeladen werden. Der Inhalt Dynamik des starren Körpers - Bewegungsgleichungen - Starre Körper mit elastischen und kinematischen Verbindungselementen - Integrationsverfahren - Rekursiver Algorithmus - Differential-Algebraische Gleichungen - Analyse von Mehrkörpersystemen - Anwendungs- und Übungsbeispiele aus der Technik Die Zielgruppen Studenten des Maschinenbaus, der Elektrotechnik und Mechatronik sowie der Biomechanik an Hochschulen und Universitäten Ingenieure in der Praxis, die sich mit Fragestellungen der Mehrkörpersimulation (MKS) befassen Entwickler aus der Kfz-Technik sowie Fachleute aus F+E Die Autoren Dr.-Ing. Georg Rill ist Professor mit den Lehrgebieten Technische Mechanik, Ingenieurinformatik, Fahrdynamik, Mehrkörperdynamik sowie Laborleiter Fahrdynamik. Dr.-Ing. Thomas Schaeffer ist Professor mit den Lehrgebieten Konstruktion, CAD, Maschinenelemente und Getriebetechnik, Mehrkörpersysteme und Bewegungstechnik sowie Laborleiter Mehrkörpersimulation, beide an der Ostbayerischen Technischen Hochschule (OTH) Regensburg. Y1 - 2014 U6 - https://doi.org/10.1007/978-3-658-06084-8 PB - Springer CY - Berlin ER - TY - JOUR A1 - Rill, Georg A1 - Schuderer, Matthias T1 - A Second-Order Dynamic Friction Model Compared to Commercial Stick–Slip Models JF - Modelling N2 - Friction has long been an important issue in multibody dynamics. Static friction models apply appropriate regularization techniques to convert the stick inequality and the non-smooth stick–slip transition of Coulomb’s approach into a continuous and smooth function of the sliding velocity. However, a regularized friction force is not able to maintain long-term stick. That is why dynamic friction models were developed in recent decades. The friction force depends herein not only on the sliding velocity but also on internal states. The probably best-known representative, the LuGre friction model, is based on a fictitious bristle but realizes a too-simple approximation. The recently published second-order dynamic friction model describes the dynamics of a fictitious bristle more accurately. It is based on a regularized friction force characteristic, which is continuous and smooth but can maintain long-term stick due to an appropriate shift in the regularization. Its performance is compared here to stick–slip friction models, developed and launched not long ago by commercial multibody software packages. The results obtained by a virtual friction test-bench and by a more practical festoon cable system are very promising. Thus, the second-order dynamic friction model may serve not only as an alternative to the LuGre model but also to commercial stick–slip models. KW - commercial stick–slip friction models KW - dynamic friction model KW - long-term stick KW - multibody dynamics Y1 - 2023 U6 - https://doi.org/10.3390/modelling4030021 SN - 2673-3951 N1 - Corresponding author: Georg Rill VL - 4 IS - 3 SP - 366 EP - 381 PB - MDPI ER - TY - GEN A1 - Sterner, Michael A1 - Schumm, Leon T1 - Netzpuffer – Speicher & Kraftwerke als virtuelle Leitungen für mehr Versorgungssicherheit und EE-Integration in Nord und Süd T2 - 7. Smart-Grid-Fachtagung WAGO, Hannover, 29. Sept. 2021 KW - Stromspeicher KW - Batterien KW - Netzpuffer KW - Stromnetz Y1 - 2021 ER - TY - RPRT A1 - Sterner, Michael A1 - Schumm, Leon A1 - Rank, Daniel A1 - Hofrichter, Andreas T1 - Intelligente Netzpuffer : Abschlussbericht (24.01.2021) KW - Stromspeicher KW - Batterien KW - Netzpuffer KW - Stromnetz Y1 - 2021 N1 - unveröffentlichter Abschlussbericht ER - TY - JOUR A1 - Walter, Stefanie A1 - Schwanzer, Peter A1 - Hagen, Gunter A1 - Rabl, Hans-Peter A1 - Dietrich, Markus A1 - Moos, Ralf T1 - Combined Ash and Soot Monitoring for Gasoline Particulate Filters Using a Radio-Frequency-Based Sensor JF - Emission Control Science and Technology N2 - Increasingly stringent emission limits have made particulate filters necessary for gasoline engines. Similar to diesel applications, gasoline particulate filters (GPFs) can be monitored by differential pressure measurement or by the radio-frequency-based filter diagnosis (RF sensor). In addition to measuring the soot loading, ash detection is critical for monitoring the GPF over the entire vehicle lifetime. Because the RF sensor detects the filter loading through a change in the dielectric properties of the GPF, it can detect not only soot but also ash. In diesel applications, the RF sensor has already demonstrated its potential for ash detection. To verify the feasibility of simultaneous ash and soot monitoring for GPFs, filters were loaded with ash on an engine test bench and measured on a lab test bench under defined synthetic exhaust gas conditions. By evaluating resonant modes, soot and ash could be clearly distinguished, as ash mainly affects the resonant frequency, while soot also changes the quality factor due to its high dielectric losses. However, higher soot loadings could not be detected by the resonant parameters, but instead by a frequency-averaged transmission signal. While the presence of ash caused an offset in this signal, its sensitivity to soot was not affected. Thus, the influence of ash can be corrected if the signal in the soot-free filter state is known, e.g., from the behavior of the resonant parameters. Therefore, even with a continuously increasing ash loading over the lifetime of a vehicle, an accurate soot detection is possible with the RF sensor. KW - Gasoline particulate flter KW - Radio-frequency KW - Soot mass determination KW - Ash detection Y1 - 2023 U6 - https://doi.org/10.1007/s40825-023-00235-y PB - Springer ER - TY - GEN A1 - Walter, Stefanie A1 - Schwanzer, Peter A1 - Hagen, Gunter A1 - Rabl, Hans-Peter A1 - Dietrich, Markus A1 - Moos, Ralf T1 - Combined Ash and Soot Monitoring in Gasoline Particulate Filters with a Radio-Frequency-Based Sensor T2 - SAE World Congress Experience, April 5-7, 2022, Detroit, Michigan, USA N2 - In recent years, it turned out that primarily the number of ultrafine particles and not their mass is relevant in terms of harmful health effects. Therefore, exhaust emission standards are constantly being tightened with regard to the particulate number. To meet the emission limits, particulate filters have become necessary for gasoline engines. Similar to diesel applications, gasoline particulate filters (GPFs) can be monitored via differential pressure measurement or via a radio-frequency approach (RF-sensor). The latter is based on the influence of the soot conductivity on the electromagnetic field. To control the GPF, ash detection is of crucial importance besides the soot load monitoring. With the differential pressure system, this is only possible with high uncertainties due to the low pressure increase caused by ash. The RF-sensor, however, has already demonstrated its potential for ash detection in diesel applications. In order to verify the applicability of the system for GPFs, filters were loaded via a method for fast ash loading. Thereby, it was shown that by evaluating resonant modes – especially the resonant frequency – the ash loading can easily be measured as long as the filter is soot-unloaded. In contrast, soot loading can be determined independently from this by considering a frequency-averaged transmission signal between the antennas of the RF-sensor. Using a setup for radio-frequency material characterization, the dielectric parameters of the generated ash were also measured. In comparison with the properties of the synthetic soot PrintexU, ash showed significantly lower dielectric losses. Thus, the evaluation of the loss-dependent quality factor, which is only possible at low soot loadings, allows a precise conclusion whether the filter is completely soot-free. Furthermore, using synthetic soot loading, it could be shown that soot detection via the averaged transmission signal is not affected by ash. In summary, it could be shown that with the RF-sensor, ash and soot can be simultaneously detected. Y1 - 2022 UR - https://eref.uni-bayreuth.de/id/eprint/69506 ER - TY - INPR A1 - Schumm, Leon A1 - Abdel-Khalek, Hazem A1 - Brown, Tom A1 - Ueckerdt, Falko A1 - Sterner, Michael A1 - Fioriti, Davide A1 - Parzen, Max T1 - The impact of temporal hydrogen regulation on hydrogen exporters and their domestic energy transition N2 - As global demand for green hydrogen rises, potential hydrogen exporters move into the spotlight. However, the large-scale installation of on-grid hydrogen electrolysis for export can have profound impacts on domestic energy prices and energy-related emissions. Our investigation explores the interplay of hydrogen exports, domestic energy transition and temporal hydrogen regulation, employing a sector-coupled energy model in Morocco. We find substantial co-benets of domestic climate change mitigation and hydrogen exports, whereby exports can reduce domestic electricity prices while mitigation reduces hydrogen export prices. However, increasing hydrogen exports quickly in a system that is still dominated by fossil fuels can substantially raise domestic electricity prices, if green hydrogen production is not regulated. Surprisingly, temporal matching of hydrogen production lowers domestic electricity cost by up to 31% while the effect on exporters is minimal. This policy instrument can steer the welfare (re-)distribution between hydrogen exporting firms, hydrogen importers, and domestic electricity consumers and hereby increases acceptance among actors. KW - Energy Transition KW - Hydrogen regulation KW - Hydrogen export KW - Climate-neutral KW - Domestic prices KW - Hydrogen prices KW - Power-to-X Y1 - 2024 U6 - https://doi.org/10.21203/rs.3.rs-4285425/v1 N1 - Der Aufsatz wurde peer-reviewed veröffentlicht und ist ebenfalls in diesem Repositorium verzeichnet unter: https://opus4.kobv.de/opus4-oth-regensburg/8485 PB - Research Square Platform LLC ER - TY - JOUR A1 - Tremmel, Florian A1 - Nagler, Oliver A1 - Kutter, Christoph A1 - Holmer, Rainer T1 - Mechanical robustness analysis of semiconductors with a single needle probe card using acoustic emissions JF - e-Journal of Nondestructive Testing N2 - The combination of indentation testing and acoustic emission (AE) is widely used to analyze the fracture toughness of test substrates. In the manufacturing of semiconductor devices this material parameter also plays an important role. During the so-called wafer testing inside a wafer prober small probe tips are pressed onto the chip surface to check its performance. To prevent damaging the chip by that, the fracture toughness and load limit of it has to be defined in a prequalification step. This paper presents a test system that imitates the wafer testing process as close as possible and uses acoustic emission to detect appearing cracks and thereby also the load limit. The frontend of the test setup consists of a modular single needle probe card which can be placed in a wafer prober. Also, the indenter properties (tip diameter, stiffness, etc.) can be adjusted to the probe used later on during productive wafer testing to ensure realistic probing conditions. A piezoelectric sensor and a full strain gauge Wheatstone bridge are implemented close to the single indenter to measure the AEs and the applied contact force respectively. The signal-to-noise-ratios (SNRs) of both sensors are improved with an own analog amplifier module before recording them with an USB oscilloscope. A developed measurement software (LabVIEW) is used to adjust measurement parameters (trigger limit, record length, conversion factors, etc.) and automatically store and separate measurement data from different acoustic events and imprints. To evaluate the result files a second software tool (MATLAB) reads the files out and clusters the recorded events to separate crack signals from electrical and mechanical disturbances. With a prototype first test results are generated and the functionality and accuracy of the measurement concept is proven. KW - Acoustic Emission KW - Crack probability distribution KW - Fracture load limit KW - Wafer testing Y1 - 2024 U6 - https://doi.org/10.58286/30254 SN - 1435-4934 VL - 29 IS - 10 PB - NDT.net ER - TY - RPRT A1 - Volkenhoff, Tobias A1 - Gerstenberger, Marcus A1 - Breitbarth, Lutz A1 - Carstensen, Christian A1 - Dölger, Reiner A1 - Feldges, Michael A1 - Hegewald, Jessica A1 - Mutzbauer, Johannes A1 - Rose, Martin A1 - Schopf, Hans Jürgen A1 - Schroth, Max A1 - Schwietering, Christoph A1 - Seidel, Christian A1 - Sievers, Ariane A1 - Spangler, Matthias A1 - Trupat, Stefan A1 - Üstün, Ellen T1 - H NBA - Hinweise zum Einsatz von Netzbeeinflussungsanlagen KW - Verkehrstechnik KW - Netzbeeinflussungsanlagen KW - Verkehrsmanagement Y1 - 2025 SN - 978-3-86646-434-8 IS - 310/1 PB - FGSV CY - Köln ET - Ausgabe 2025 ER - TY - JOUR A1 - Schumm, Leon A1 - Brown, Tom A1 - Abdel-Khalek, Hazem A1 - Ueckerdt, Falko A1 - Sterner, Michael A1 - Fioriti, David A1 - Parzen, Max T1 - The impact of temporal hydrogen regulation on hydrogen exporters and their domestic energy transition JF - Nature Communications N2 - As global demand for green hydrogen rises, potential hydrogen exporters move into the spotlight. While exports can bring countries revenue, large-scale on-grid hydrogen electrolysis for export can profoundly impact domestic energy prices and energy-related emissions. Our investigation explores the interplay of hydrogen exports, domestic energy transition and temporal hydrogen regulation, employing a sector-coupled energy model in Morocco. We find substantial co-benefits of domestic carbon dioxide mitigation and hydrogen exports, whereby exports can reduce market-based costs for domestic electricity consumers while mitigation reduces costs for hydrogen exporters. However, increasing hydrogen exports in a fossil-dominated system can substantially raise market-based costs for domestic electricity consumers, but surprisingly, temporal matching of hydrogen production can lower these costs by up to 31% with minimal impact on exporters. Here, we show that this policy instrument can steer the welfare (re-)distribution between hydrogen exporting firms, hydrogen importers, and domestic electricity consumers and hereby increases acceptance among actors. KW - Energy Transition KW - Hydrogen regulation Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-84857 N1 - Die Preprint-Version ist ebenfalls in diesem Repositorium verzeichnet unter: https://opus4.kobv.de/opus4-oth-regensburg/7272 VL - 16 PB - Nature CY - London ER - TY - RPRT A1 - Bhardwaj, Prakhar A1 - Hauer, Franziska A1 - Mücke, Vanessa A1 - Dotter, Caroline A1 - Haug, Sonja A1 - Weikl, Simone A1 - Weber, Karsten T1 - Recording and understanding multi- and intermodal mobility - a review N2 - The transition to sustainable mobility requires detailed knowledge of actual mobility behavior. Recording mobility behavior through conventional, aggregated, or retrospective survey methods (e.g., counting stations, travel diaries) may yield incomplete insights. In addition, these methods are often expensive, prone to error, or not scalable. The aim of this literature review is to provide a systematic overview of the current state of the literature on recording and analysis of individual mobility data and, based on this, to identify possible research gaps and potential. The exploratory literature review includes social science surveys on multi- and intermodal mobility behavior, as well as an overview of possible ways to analyze travel data. The focus of the latter is on identifying relevant data sources and methodological approaches for segmentation, identification of transport mode, and trip purpose determination. Results from recent studies show that sensor-based data collection alone is not sufficient to fully and accurately map mobility behavior. One possible solution is a “best-of-both-worlds” approach that combines passive, automatic mobility data collection via smartphone sensors with targeted user corrections and additions (“human-in-the-loop”) within an app. The literature review shows that this approach yields the best data quality. Combining mobility surveys with passive collection of mobility data provides a comprehensive, accurate, and complete overview of mobility behavior. KW - multimodal mobility KW - mobility Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-87427 CY - Regensburg ER - TY - GEN A1 - Rahim, Stefan A1 - Schumm, Leon T1 - Weather Data Cutouts for the Wasserstoffatlas (Hydrogen Map) [Data set] N2 - The cutouts are required to calculate the solar PV and wind onshore feed-in profiles of the Wasserstoffatlas. The provided cutouts are spatiotemporal subsets of the European weather data from the ECMWF ERA5 reanalysis dataset and the CMSAF SARAH-2 solar surface radiation dataset for the year 2013. They have been prepared by and are for use with the atlite tool (https://atlite.readthedocs.io/). ECMWF ERA5 Source: https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-single-levels?tab=overview Terms of Use: https://cds.climate.copernicus.eu/api/v2/terms/static/20180314_Copernicus_License_V1.1.pdf CMSAF SARAH-2 Pfeifroth, Uwe; Kothe, Steffen; Müller, Richard; Trentmann, Jörg; Hollmann, Rainer; Fuchs, Petra; Werscheck, Martin (2017): Surface Radiation Data Set - Heliosat (SARAH) - Edition 2, Satellite Application Facility on Climate Monitoring, DOI:10.5676/EUM_SAF_CM/SARAH/V002, https://doi.org/10.5676/EUM_SAF_CM/SARAH/V002 Terms of Use: https://www.eumetsat.int/cs/idcplg?IdcService=GET_FILE&dDocName=pdf_leg_data_policy&allowInterrupt=1&noSaveAs=1&RevisionSelectionMethod=LatestReleased Y1 - 2023 U6 - https://doi.org/10.5281/zenodo.8135586 ER - TY - GEN A1 - Birett, Falk A1 - Schumm, Leon A1 - Hofrichter, Andreas A1 - Heusgen, Valentin A1 - Rahim, Stefan T1 - Wasserstoffatlas Deutschland (Hydrogen Map) [Data set] N2 - Input files required for Hydrogen Map workflow in the project "Wasserstoffatlas Deutschland", funded by the BMBF. Y1 - 2025 U6 - https://doi.org/10.5281/zenodo.13960465 N1 - Further versions linked on Zenodo. ER - TY - CHAP A1 - Hinterreiter, Marion A1 - Brückl, Oliver A1 - Rauch, Johannes ED - Schulz, Detlef T1 - Methodology for long-term reactive power forecasts of medium-voltage grids T2 - NEIS 2025 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg, September 15 – 16, 2025 N2 - Understanding and assessing the long-term behavior of reactive power is crucial for power system planning and invest-ment decisions. This is particularly growing relevant for the lower voltage-grid levels, which are gaining importance due to significant changes in grid behavior, operational strategies, energy generation and consumption patterns. Currently, standardized methodologies for forecasting reactive power in medium-voltage grids are lacking, creating a gap in research and practical applications. To optimize grid investments and expansions, informed decisions based on reliable research and accurate forecasts are essential. This paper presents a methodology for long-term reactive power forecasting in me-dium-voltage grids, introducing a new approach to account for low- and medium-voltage grid interactions while address-ing common challenges like limited available grid data and scenario framework definition. The aim of the forecast is the future reactive power behaviour of a medium-voltage-grid at the high-voltage side of the high-voltage to medium-voltage transformer. The medium-voltage-level is modelled using a grid model approach, while low-voltage grids are being mod-elled using generic distribution grids. A 209-bus medium-voltage-grid model is used as an application example and to provide two exemplary use cases for a reactive power forecast for 2045. KW - reactive power KW - forecasting KW - long-term KW - medium-voltage level KW - grid level interaction Y1 - 2025 SN - 978-3-8007-6633-8 SP - 218 EP - 223 PB - VDE Verlag ER - TY - CHAP A1 - Stadler, Andreas A1 - Kraus, Hermann A1 - Brückl, Oliver ED - Technische Universität München, T1 - Proposing an Optimization Model for a techno-economic Evaluation of Energy Storage Systems T2 - PESS 2025 – IEEE Power and Energy Student Summit, October 08 – 10, 2025 in Munich, Germany N2 - During the global energy crisis in 2022, electricity prices increased drastically. This lead, together with an overall higher price volatility to possibly higher electrical energy storage system (ESS) profitability. To test if the investment in an ESS can now be more profitable, an approach for a techno-economic evaluation of ESS is presented in this paper, using an optimization algorithm to determine the optimal way of covering a load flow profile with electricity trading products on the electricity market with and without the use of an energy storage system. The cost differences between using or not using the storage system are assumed to be the profits of the ESS, which must exceed the (interest-bearing) investment costs over its lifetime. The correct way of operation of the optimization model is validated and several storage sizes and capacities as well as several years of the electricity market data was analyzed, once with a perfect forecast of all prices of the electricity trading products and once with a forecast based on the previous years purchasing strategy. The results show that, using the prognosis and a 2 % p.a. interest rate, only the storage combinations for 2.5 MWh/ 2.5 MW and 1 MWh/ 1 MW show profitability in 2023, whereas 2017 and 2020 show no profitability. KW - energy storage systems KW - techno economic evaluation KW - electricity trading KW - optimization KW - ess profitability Y1 - 2025 SN - 978-3-8007-6656-7 SP - 97 EP - 102 PB - VDE ER - TY - CHAP A1 - Hinterreiter, Marion A1 - Brückl, Oliver A1 - Rauch, Johannes ED - Technische Universität München, T1 - Challenges and Approaches for Long-Term Reactive Power Forecasting in Power Systems T2 - PESS 2025 – IEEE Power and Energy Student Summit, October 08 – 10, 2025 in Munich, Germany N2 - The transition from fossil fuels to renewable energy sources is driving profound changes across all voltage levels of the electrical grid, altering active power (P) as well as reactive power (Q) behavior. This transformation involves a shift from predominantly top-down, unidirectional electricity flows to bidirectional and increasingly complex flow patterns, fundamentally altering the operation and utilization of power systems. Many countries are already reporting notable changes in their transmission grid Q. This can lead to increased costs for grid expansion and compensation equipment, as well as grid losses. To minimize these losses and ensure grid stability and efficiency, understanding and forecasting Q long-term becomes essential. This paper addresses the challenges of long-term (1-20 years) Q forecasting in general by analyzing Q behavior in grids, the main influencing grid parameters, and reviewing existing forecasting approaches. It evaluates the applicability of these approaches and highlights current research gaps and trends. By focusing on this underexplored area, the paper aims to support the development of more advanced and reliable long-term Q forecasting techniques. KW - reactive power KW - forecasting KW - long-term KW - network models Y1 - 2025 SN - 978-3-8007-6656-7 SP - 109 EP - 114 PB - VDE Verlag ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver A1 - Engel, Bernd ED - Schulz, Detlef, T1 - Optimal Reactive Power Planning by covering deficient voltage demands with additional reactive power sources using a sensitivity approach T2 - NEIS 2023 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg, September 4 – 5, 2023 N2 - The determination of the optimal location, types and size of additional required reactive power sources is a main interest of Reactive Power Planning (RPP) investigations and of this paper. The planning problem addresses the maintenance of voltage stability, which is an ancillary service in Germany, and can be formulated as a mixed-integer optimization prob-lem. The aim of this work is a techno-economically efficient coverage of the deficient steady state voltage deviation demands (VDD) by placing new reactive power sources with adequate size or extending the reactive power potential of existing sources. An optimization model is set up to solve the planning problem by using load flow voltage sensitivities, which quantify and evaluate the technical efficiency of new reactive power sources in relation to the present voltage deviation demands. Operating and investment costs are used as economic decision parameters. Within an application example, which is carried out with an exemplary transmission system, the solution of the planning problem is discussed. KW - reactive power planning KW - voltage control KW - optimal power flow KW - sensitivity analysis KW - system planning Y1 - 2023 UR - https://ieeexplore.ieee.org/document/10556672 SN - 978-3-8007-6134-0 SP - 223 EP - 230 PB - VDE Verlag CY - Berlin ER - TY - THES A1 - Thema, Martin Jiří T1 - Process optimization for microbial biosynthesis of methane in a trickle-bed reactor for Power-to-Gas applications: the ORBIT-process N2 - This thesis identifes Power-to-Gas in general and biological CO2-methanation in trickle-bed reactors in particular as promising energy storage and sector coupling technology ready for application but with further optimization potential. It reviews the global status and development of Power-to-Gas technology as to be of exponentially growing importance in energy systems changing towards renewable power supply and analyzes optimization and standardization potential for biological CO2-methanation in tricklebed reactors deriving an improved methanation process. Process development and experiments on hydrodynamical and biological improvement of such a setup were performed, leading to an optimized combination of a packing and microorganisms in pure culture embedded in the new ORBIT-process. First experimental results give evidence of successful application of different optimization approaches implemented in a technical center scale setup. N2 - Die vorliegende Arbeit analysiert Status und Entwicklung der Power-to-Gas-Technologien Wasserelektrolyse und CO2-Methanisierung hinsichtlich Kosten, technischer Parameter und energiepolitischer Stellung in den wichtigsten Einsatzländern. So konnte ein exponentieller Trend in zugebauter Anlagenleistung sowie deutliche Investitionskostendegressionen für alle untersuchten Technologien abgeleitet werden. Die Arbeit entwickelt Optimierungs- und Standardisierungsansätze für die biologische CO2-Methanisierung im Rieselbett-Reaktor, welche als eine der vielversprechenden Power-to-Gas-Anwendungen identifiziert wird. Mit Versuchen zur Verbesserung der hydrodynamischen Bedingungen im Reaktor sowie zu einer optimierten Verbindung aus Packungselementen und Mikroorganismen in Reinkultur wird daraus der neue ORBIT-Prozess abgeleitet. Erste Versuchsergebnisse aus einer realisierten Anlage im Technikumsmaßstab deuten hin auf die erfolgreiche Umsetzung der identifzierten Optimierungsansätze. T2 - Prozessoptimierung zur biologischen CO2-Methanisierung im Rieselbettreaktor f¨ur Power-to Gas-Anwendungen: der ORBIT-Prozess KW - CO2-methanation KW - ORBIT-process KW - Power-to-Gas KW - biological methanation KW - biomethanation KW - trickle-bed reactor Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?https://nbn-resolving.org/urn:nbn:de:bvb:29-opus4-150567 SN - 978-3-8440-7656-1 ER - TY - THES A1 - Mühlbauer, Christian T1 - Entwicklung einer Methodik zur Bewertung und Optimierung des vibroakustischen Verhaltens von Kraftstoffeinspritzsystemen N2 - Die vorliegende Dissertation befasst sich mit der akustischen Analyse von Kraftstoffein-spritzsystemen und deren NVH-Optimierung mithilfe ansteuerungstechnischer Maßnahmen. Da sich der Körper- und Luftschall beim Betrieb des Verbrennungsmotors mit anderen, nicht untersuchungsrelevanten Geräuschkomponenten überlagert, ist im Vollmotorbetrieb eine diffe-renzierte komponentenbasierte Geräuschmessung nicht möglich. Deshalb wurde ein NVH-Sys-temprüfstand entwickelt, der eine isolierte akustische Vermessung von Einspritzsystemen im seriennahen Systemverbund ermöglicht. Die Betriebsparameter des Einspritzsystems wurden an einem Vollmotor in einem leerlaufna-hen Motorbetriebspunkt erfasst und mithilfe eines speziellen Entwicklungssteuergeräts auf den NVH-Systemprüfstand transferiert. Ausgehend von dem definierten Referenzbetriebspunkt wurden sowohl die Randbedingungen als auch die Ansteuerstrategie variiert und deren Einfluss auf das akustische Verhalten analysiert. Dabei zeigten primär der Raildruck und die Anzahl der Einspritzungen einen ausgeprägten Einfluss auf die betrachteten (psycho-)akustischen Parame-ter Schalldruckpegel, Lautheit, Schärfe und Impulshaltigkeit. Zur akustischen Optimierung der mechatronischen Komponenten wurden zum einen der An-steuerstrom reduziert und zum anderen ein Bremsimpuls am Ende der Ansteuerung implemen-tiert. Dadurch konnten die mechanischen Prellereignisse deutlich reduziert werden. Mithilfe eines Einspritzratenmessgeräts wurde allerdings nachgewiesen, dass sich die Optimierungs-maßnahmen insbesondere auf die Streuung der eingespritzten Kraftstoffmasse negativ auswir-ken und damit ein Zielkonflikt aus Geräuschqualität und Primärfunktionen entsteht. Als signi-fikanter Kipppunkt wurde bei den Injektoren der Übergang vom linearen Vollhub-Betrieb zum ballistischen Teilhub-Betrieb identifiziert. Aus diesem Grund wurde die elektrische Ansteue-rung unter der Voraussetzung des Injektor-Vollhub-Betriebs optimiert. Bei der Beurteilung des Einflusses der NVH-optimierten Ansteuerprofile auf die Robustheit der mechatronischen Komponenten wirkten sich eine niedrige Versorgungsspannung sowie eine kurze Ansteuerdauer der Injektoren besonders negativ auf die Streuung der eingespritzten Kraftstoffmasse aus. Vor allem in Verbindung mit der stromreduzierten Ansteuerung wurden die Injektoren nicht mehr zuverlässig und reproduzierbar im Voll-Hub geöffnet. Weiterhin wur-den durch die Bremspuls-Applikation injektorspezifische Abweichungen im Schließverhalten weiter verstärkt und erhöhten damit auch die Abweichungen der mittleren eingespritzten Kraft-stoffmasse zwischen den untersuchten Injektor-Exemplaren. Abschließend wurde die Übertragbarkeit des Systemverhaltens ermittelt, indem die Optimie-rungsmaßnahmen auf einen weiteren Versuchsträger ausgeweitet wurden. Dabei zeigte sich, dass die Maßnahmen zwar grundsätzlich übertragbar waren, aber die Parametrierung bezüglich Ansteuerstromreduzierung und Bremspuls-Applikation zum Teil stark angepasst werden mussten. N2 - The present dissertation deals with the acoustic analysis of fuel injection systems and their NVH optimization by means of control measures. Since the structure-borne and airborne sound dur-ing operation of the combustion engine is superimposed with other noise components that are not relevant for the analysis, a differentiated component-based noise measurement is not possi-ble in full engine operation. For this reason, an NVH system test bench has been developed that enables isolated acoustic measurements of fuel injection systems in a near-series system com-pound. The operating parameters of the injection system were recorded on a full engine at an engine operating point close to idle and transferred to the NVH system test bench by means of a special development control unit. Beginning from the defined reference operating point, both the boundary conditions and the control strategy were varied and their influence on the acoustic behavior analyzed. Primarily, the rail pressure and the number of injections had a distinct in-fluence on the (psycho-)acoustic parameters considered: sound pressure level, loudness, sharp-ness and impulsiveness. To optimize the mechatronic components acoustically, the control current was reduced and a braking pulse was implemented at the end of the control. This significantly reduced the me-chanical bounce events. However, using an injection rate measurement device revealed that the optimization measures had a particularly negative effect on the scattering of the injected fuel mass, resulting in a trade-off between noise quality and performance. To this, the shift from linear full-stroke operation to ballistic partial-stroke operation of the injectors was identified as a significant tipping point. Therefore, the electrical control was optimized under the condition of injector full stroke operation. Considering the influence of the NVH optimized control profiles on the robustness of the mech-atronic components, particularly a low supply voltage and a short control duration of the injec-tors showed a negative effect on the scattering of the injected fuel mass. Especially in combi-nation with the reduced control current, the injectors were no longer able to open reliably and reproducibly in the full stroke. Additionally, the brake pulse application further increased in-jector-specific deviations in the closing behavior and thus increased the deviations of the mean injected fuel mass between the injector samples investigated. Finally, the transferability of the system behavior was determined by extending the optimization measures to another demonstrator. It turned out that the measures were generally transferable, but the parameterization with regard to control current reduction and brake pulse application had to be adapted considerably in some cases. KW - Brennstoffe KW - Explosivstoffe KW - Kraftstoffe KW - Technik der Verkehrsmittel Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:ma9:1-1981185920-1115312 ER - TY - THES A1 - Schwanzer, Peter T1 - Experimentelle Untersuchungen zur On-Board Überwachung von Partikelfiltern für den Einsatz an direkteinspritzenden Benzinmotoren N2 - This thesis deals with the development of a methodology for an improved on-board diagnosis of particulate filters in vehicles with gasoline direct injection (GDI) technology with regard to future emission legislations. In order to comply with statutory particle number limits, particulate filters are used in the exhaust gas aftertreatment for GDI-engines. The currently applied method for diagnostic purposes, a differential pressure sensor, will not be suitable for future legislations. Therefore, an on-board strategy with real-time ability shall be developed. To achieve this, the application of novel sensor concepts has been investigated, namely electrostatic soot sensors (ePM sensor) and radio frequency antennas (RF sensor). Due to the results of the ePM-sensors, no methodology for an on-board diagnosis based on an ePM sensor concept was made. The RF sensor showed varying sensitivities for different soot and different quantities of volatile components in the filter element. The analysis of the oxidation processes showed that the regeneration of the filter element is detected by the RF sensor. Furthermore, the stored amount of ash could be captured. Due to these findings, a concept for an improved on-board diagnosis strategy by means of an RF sensor concept was developed. In the course of the work it turned out that a combined sensor concept consisting of a differential pressure sensor and a RF sensor is most suitable. In a validation process, this sensor concept showed sufficient results concerning the detection capability of soot and ash loads as well as of the degree of damage of particulate filters. Especially for small amounts of ash, this sensor concept showed specific advantage. Also, the determination of the current amount of soot in the filter element proved to be suitable. Regarding the detection of damages, the sensor concept convinces through a higher sensitivity. KW - GDI KW - GPF KW - On-Board-Monitoring Y1 - 2022 SN - 978-3-8439-5101-2 PB - Verlag Dr. Hut CY - München ER - TY - THES A1 - Grauvogl, Dominik ED - Gerling, Dieter T1 - Multiphysikalische Auslegung einer fremderregten Synchronmaschine mit magnetischer Asymmetrie für einen Hochvolt-Achsantrieb N2 - In der vorliegenden Arbeit wird eine fremderregte Synchronmaschine als Achsantrieb für ein Elektrofahrzeug entwickelt. Als Grundlage hierfür dient ein bereits vorhandener Stator einer permanenterregten Synchronmaschine. Durch die Wiederverwendung des Stators ist eine maschinentypunabhängige Baukastenerweiterung in Form eines magnetfreien Rotors gegeben, wodurch die ökonomischen und ökologischen Nachteile der Permanentmagnete ausgeschlossen sind. Bei der Auslegung des Rotors wird von Beginn an ein multiphysikalischer Entwicklungsansatz gewählt, mit dem der praxistaugliche Einsatz für den modularen Baukasten sichergestellt ist. Dabei ist die elektromagnetische Auslegung iterativ auf die mechanische Blechpaketfestigkeit, das thermische Verhalten und die magnetischen Geräusche abgestimmt. In Kombination mit den gesetzten Restriktionen ergibt sich ein neuartiges asymmetrisches Polschuhdesign mit dem es möglich ist, das geforderte Drehmoment mit genügend kleiner Welligkeit ohne eine Rotorschrägung zu erreichen. Die Simulationsergebnisse sind durch die Vermessung eines aufgebauten Prototyps validiert und bestätigt. Ein abschließender Simulationsvergleich mit der baugleichen permanenterregten Synchronmaschine zeigt, dass die fremderregte Synchronmaschine hinsichtlich Performance, Wirkungsgrad und Geräuschverhalten eine konkurrenzfähige Alternative dazu ist. KW - Magnetische Asymmetrie KW - Traktionsmotor KW - Elektroantrieb KW - E-Mobilität KW - magnetfreier Antrieb KW - magnetische Geräusche KW - NVH KW - elektromagnetische Auslegung KW - Magnetkreisberechnung KW - Rotorkühlung KW - Luftkühlung KW - Erregerstromoptimierung KW - FEM KW - mechanische Festigkeit Y1 - 2022 UR - https://www.shaker.de/de/content/catalogue/index.asp?lang=de&ID=8&ISBN=978-3-8440-8553-2 SN - 9783844085532 PB - Shaker Verlag CY - Düren ER - TY - THES A1 - Weber, Sebastian T1 - Charakterisierung verschiedener Wassereinspritztechnologien für Ottomotoren N2 - Die Reduktion von Kraftstoffverbrauch und Schadstoffemission bei gleichzeitiger Verbesserung der Fahrleistung bei kleinerem Hubraum und reduzierter Zylinderzahl, die erhöhte Performance und die Kompatibilität mit elektrifizierten Komponenten beschreiben die aktuellen Ziele und Herausforderungen der modernen Ottomotorentwicklung. Um alle Herausforderungen zu erfüllen, muss ein stöchiometrischer Betrieb sichergestellt werden. Dabei kann es jedoch an der Volllast zur Überschreitung thermischer Grenzen im Abgaspfad kommen, weswegen die Abgastemperatur ohne Leistungsverluste abgesenkt werden muss. Die Wassereinspritzung kombiniert Downsizing, Leistungssteigerung und die Verbesserung der Schadstoffemissionen wirkungsvoll miteinander und könnte einen Beitrag zur Erreichung der Klimaziele leisten. Um ein optimales Systemlayout zu erarbeiten, sind prozessuale Betrachtungen oft nicht ausreichend. Vielmehr müssen die Phänomene im Brennraum beobachtet werden. Schwerpunktmäßig sind dies die Einbringung des Wassers, der Wandkontakt, die Spray- und Wandfilmverdampfung und somit die Wirksamkeit der Abgastemperaturreduktion und die Verbesserung des indizierten Wirkungsgrads. In einem ersten Schritt werden die Thermodynamik bei Wassereinspritzung analysiert und verschiedene Einspritztechnologien miteinander verglichen. Fokussiert wird die Verbrennung, die Veränderung in den gasförmigen und festen Abgasbestandteilen und die mechanische Belastung der Aggregate durch die Verbesserung der Zündwinkel. Die Mischungseinspritzung über den zentralen Hochdruckinjektor vereint den geringsten Wasserverbrauch mit bestmöglicher Schwerpunktlage, starker Reduktion des Partikelausstoßes und akzeptabler Erhöhung der mechanischen Belastung und ist damit das favorisierte Konzept. Neben den prozessualen Betrachtungen werden mit einem optisch zugänglichen Versuchsträger zwei laseroptische Messtechniken zur Visualisierung flüssigen Wassers und der spektralen Trennung zwischen Wasser und Kraftstoff entwickelt und validiert. Damit werden die verschiedenen Varianten optisch vermessen und die Sensitivität gegenüber veränderten Betriebs- und Randbedingungen ermittelt. Die Sammlereinspritzung zeigt die größten Tropfen, gefolgt von der Saugrohr- und der Mischungseinspritzung. Auch hat diese den mit Abstand größten Wandkontakt und die geringste Verdampfungsrate, ist zusätzlich anfällig für zyklische Schwankungen. Die Saugrohreinspritzung kennzeichnen kleine Tropfen, ein konzentriertes Einströmen durch den Ventilspalt, ein flächiger Wandfilm auf der Kolbenoberseite und die Verbesserung der Tropfenverdampfung durch Turbulenz und die Nutzung von Phasing. Favorit ist abermals die Mischungseinspritzung. Eine hohe Wandfilm- und unmittelbare Sprayverdampfung kennzeichnen das System, wobei eine Erhöhung des Einspritzdrucks die Verdampfungsrate signifikant verbessert. Außerdem ist die Einspritzdauer am geringsten und die Reproduzierbarkeit am größten, jedoch auch der applikative Aufwand. Am favorisierten System werden weitere Analysen durchgeführt, unter anderem zur Veränderung der Bauteiltemperaturen, der Vergleich mit einer Ethanoleinspritzung oder die vielversprechende Kombination in Form einer Wasser-Ethanol-Mischungseinspritzung. Auf Basis der experimentellen Erkenntnisse wird ein CFD-Verfahren vorgestellt, das die Wassereinspritzung abbildet und somit die Virtualisierung in der Produktentwicklung vorantreibt. Neben der methodischen Vorgehensweise wird das Verfahren validiert und am Einzylinder- und Vollmotorbetriebspunkt vorgestellt. Die auftretenden Unterschiede werden analysiert und ausgewählte Parameteranalysen durchgeführt. Mit den Simulationen kann nachvollzogen werden, wie das Wasser die Zylinderlaufbahn benetzt und mit dem Kolben interagiert. Zusammenfassend charakterisiert diese Arbeit die gängigen Wassereinspritzvarianten auf unterschiedlichen Ebenen, gibt Optimierungsempfehlungen für die bestmögliche Medienverdampfung und empfiehlt die Mischungseinspritzung als Systemlayout. N2 - The reduction in fuel consumption and pollutant emissions with simultaneous improving driving performance with a smaller displacement and a reduced number of cylinders, increased performance and compatibility with electrified components describe the current goals and challenges of modern gasoline engine development. In order to fulfil all challenges, stoichiometric operation must be ensured. At full load, however, thermal limits in the exhaust gas path can be exceeded, that is why the exhaust gas temperature must be reduced without loss of performance. The water injection effectively combines downsizing, increased performance and the improvement of pollutant emissions and could contribute to the achievement of the climate targets. In order to develop an optimal system layout, procedural considerations are often not sufficient. Rather, the phenomena in the combustion chamber must be observed. The focus is on the introduction of water, wall contact, spray, and wall film evaporation and thus the effectiveness of the exhaust gas temperature reduction and the improvement of the indicated efficiency. In a first step, the thermodynamics of water injection are analyzed, and different injection technologies compared. The focus is on the combustion, the change in the gaseous and solid exhaust gas components and the mechanical load on the engines by improving the ignition angle. The mixture injection via the central high-pressure injector combines the lowest water consumption with the best possible center of gravity, a strong reduction in particle emissions and an acceptable increase in the mechanical load and is therefore the preferred concept. In addition to the procedural considerations, two laser-optical measurement methods for visualizing liquid water and the spectral separation between water and fuel are being developed and validated using an optically accessible test engine. In this way, the different variants are optically measured and the sensitivity of changed operating and boundary conditions is determined. The manifold injection shows the largest droplets, followed by the manifold and the mixture injection. This has the greatest wall contact and the lowest evaporation rate by far but is susceptible to cyclical fluctuations. The intake manifold injection is characterized by small droplets, a concentrated inflow through the valve gap, a flat wall film on the top of the piston and the improvement of droplet evaporation through turbulence plus the use of phasing. Mixture injection is once again the favorite. The system is characterized by high wall film and direct spray evaporation, with an increase in the injection pressure significantly improving the evaporation rate. In addition, the injection duration is the shortest and the reproducibility greatest, but also the application effort. Further analyzes are carried out on the favored system, including changes in component temperatures, a comparison with an ethanol injection or the promising combination in the form of a water-ethanol mixture injection. Based on the experimental findings, a CFD process is presented that maps the water injection and thus drives the virtualization in product development. In addition to the methodical approach, the process is validated and presented at the single-cylinder and production engine operating point. The differences that arise are analyzed and the influence of selected parameters are pointed out. The simulations can be used to understand how the water wets the cylinder liner and interacts with the piston. In summary, this work characterizes the common water injection variants on different levels, gives optimization recommendations for the best possible media evaporation and recommends mixed injection as a system layout. KW - Kolbenkraftmaschine KW - Kraftstoffverbrauch KW - Schadstoffemission KW - Ottomotor KW - Einspritzanlage Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:ma9:1-1981185920-884176 ER -