@article{EmbergerAltmannGebhardetal., author = {Emberger, Peter and Altmann, Robert and Gebhard, J{\"u}rgen and Thuneke, Klaus and Winkler, Markus and T{\"o}pfer, Georg and Rabl, Hans-Peter and Remmele, Edgar}, title = {Combustion characteristics of pure rapeseed oil fuel after injection in a constant volume combustion chamber with a non-road mobile machinery engine solenoid injector}, series = {Fuel}, journal = {Fuel}, number = {320}, publisher = {Elsevier}, doi = {10.1016/j.fuel.2022.123979}, abstract = {Pure rapeseed oil fuel (R100) according to standard DIN 51605 is a greenhouse gas saving option for the mobility sector. With its high energy density close to diesel fuel, R100 is suitable to operate non-road mobile machinery with a high power demand and long operating time, where electric drives reach their limits. Advantages are indicated for its use in environmentally sensitive areas like agriculture since R100 is highly biodegradable and non-toxic. However, R100 is characterised by differing physical and chemical properties compared to diesel. The objective of the research is to investigate the differences in the ignition and combustion behaviour of R100 compared to diesel fuel (DF). For this purpose, a constant volume combustion chamber is used, which is equipped with a modern solenoid injector for engines of non-road mobile machinery. The researched injector shows a different hydraulic behaviour when using R100 compared to DF in that the injected fuel mass is lower with R100 than with DF. In combination with the 14 \% by mass lower calorific value, less energy output is determined with R100. When varying the injection pressure, the impact on the ignition delay and combustion behaviour is much higher for R100 than for DF. Specifically, an increase of the injection pressure supports mixture preparation and thus partially compensates the differing physical properties of R100. The results of ignition delay measurements and net heat release analysis are as follows: At low load conditions with low injection pressure as well as a low combustion chamber temperature and pressure, R100 ignites later and shows a further delayed combustion compared to diesel. The opposite is observed for medium and high load conditions, where R100 ignites faster and without delayed combustion in comparison to DF. Thus, an adjustment of the heat release of R100 at the same level as for DF is possible by modifying the injection strategy. The research shows that for an optimised combustion of R100 the injection settings must be adjusted for every operation point separately. The results indicate how the injection parameters should be adjusted for different load conditions to realise a high-quality engine calibration for R100.}, language = {en} } @article{MonkmanSindersbergerPrem, author = {Monkman, Gareth J. and Sindersberger, Dirk and Prem, Nina}, title = {Magnetically enhanced photoconductive high voltage control}, series = {ISSS Journal of Micro and Smart Systems}, volume = {11}, journal = {ISSS Journal of Micro and Smart Systems}, publisher = {Springer Nature}, doi = {10.1007/s41683-021-00088-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-30606}, pages = {317 -- 328}, abstract = {The recent surge of interest in electrostatic actuators, particularly for soft robotic applications, has placed increasing demands on high voltage control technology. In this respect, optoelectronic bidirectional switching and analogue regulation of high voltages is becoming increasingly important. One common problem is the leakage current due to dark resistance of the material or device used. Another is the physical size of such elements. However, their ability to provide galvanic separation makes them a very attractive alternative to conventional (wired) semiconductor elements. This paper gives an overview of available methods and devices before introducing a concept based on the combination of photoresistive and magnetoresistive effects in Gallium Arsenide that are potentially applicable to other semiconductor materials.}, language = {en} } @inproceedings{LaloSailerMottoketal., author = {Lalo, Erjola and Sailer, Andreas and Mottok, J{\"u}rgen and Siemers, Christian}, title = {Overhead-Aware Schedule Synthesis for Logical Execution Time (LET) in Automotive Systems}, series = {2022 IEEE 35th International System-on-Chip Conference (SOCC): 05-08 September 2022, Belfast, United Kingdom}, booktitle = {2022 IEEE 35th International System-on-Chip Conference (SOCC): 05-08 September 2022, Belfast, United Kingdom}, publisher = {IEEE}, isbn = {978-1-6654-5985-3}, doi = {10.1109/SOCC56010.2022.9908103}, pages = {1 -- 6}, abstract = {The Logical Execution Time (LET) has recently been integrated in multi-core automotive systems to ensure timing and dataflow determinism. Although buffering mechanisms are introduced to incorporate LET semantics, they do not guarantee that tasks are executed within their LET frames. In fact, LET and buffering semantics are violated if scheduling is not designed to execute all tasks within their LET frames and in a specific order. In this paper, we describe a scheduling synthesis technique for Fixed-Priority Scheduling (FPS) to achieve resource-efficient execution of LET systems. The proposed approach considers LET semantics, scheduling overheads, and delays caused by operating system operations and provides the possibility to optimize the schedule with respect to aspects like scheduling overheads. Our performance and feasibility evaluation shows that the proposed algorithm provides results in a reasonable amount of time for models of complex industrial applications. Thus, the integration of the proposed algorithm into an automated process is of high benefit to accelerate the development of vehicle applications.}, language = {en} } @inproceedings{Franke, author = {Franke, Ariane}, title = {Electricity load forecasting for industrial microgrid and load management}, series = {Applied Research Conference 2022 Conference Proceedings: 4th July 2022, University of Applied Sciences Ansbach (Onsite Conference)}, booktitle = {Applied Research Conference 2022 Conference Proceedings: 4th July 2022, University of Applied Sciences Ansbach (Onsite Conference)}, editor = {Uhl, Christian and Walter, Michael and Stiehl, Annika}, publisher = {Hochschule Ansbach}, address = {Ansbach}, doi = {10.25929/qbwt-zf40}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-68231}, pages = {405 -- 409}, abstract = {As more energy systems from renewable sources and the electricity market becomes more volatile, new solutions to ensure the security of supply are tested. Microgrids offer a possibility to prevent construction downtime. In order to use the energy sources and storage facilities of the microgrid effectively, load forecasting algorithms are essential. Thus, in this study a short term load forecasting model for a construction company is designed, that will be used for managing a microgrid as well as the general load consumption. This paper proposes the use of the XGBoost algorithm for the 36-hour forecast including predictors based on past measurements as well as information extracted from the timestamp. Moreover, it is shown that including load profiles attained by conventional methods has the potential to improve the accuracy of the model.}, language = {en} } @incollection{BauerGawlikSterneretal., author = {Bauer, Franz and Gawlik, Julia and Sterner, Michael and Hamacher, Thomas}, title = {{\"U}bergreifende Energiesystemmodellierung}, series = {Optionen f{\"u}r ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen - Potentiale. 4. Roadmap des Kopernikus-Projektes P2X, Phase II}, booktitle = {Optionen f{\"u}r ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen - Potentiale. 4. Roadmap des Kopernikus-Projektes P2X, Phase II}, editor = {Ausfelder, Florian and Du Tran, Dinh}, publisher = {DECHEMA Gesellschaft f{\"u}r Chemische Technik und Biotechnologie e.V.}, address = {Frankfurt a.M.}, isbn = {978-3-89746-238-0}, pages = {17 -- 35}, language = {de} } @misc{WalterSchwanzerHagenetal., author = {Walter, Stefanie and Schwanzer, Peter and Hagen, Gunter and Rabl, Hans-Peter and Dietrich, Markus and Moos, Ralf}, title = {Combined Ash and Soot Monitoring in Gasoline Particulate Filters with a Radio-Frequency-Based Sensor}, series = {SAE World Congress Experience, April 5-7, 2022, Detroit, Michigan, USA}, journal = {SAE World Congress Experience, April 5-7, 2022, Detroit, Michigan, USA}, abstract = {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.}, language = {en} } @techreport{LermerHeissGierletal., author = {Lermer, Valentin josef and Heiß, Simon and Gierl, Philipp and Rappl, Veronika and Ardaya-Lieb, Samuel and M{\"o}hring, Christoph and Solisch, Matthias and Solisch, Tobias and Garschhammer, Kilian and Kammerl, Andreas and Kolb, Moritz and Hohenadler, Franz and Reber, Luis and Hartwig, Anton and Schaller, Jonas and Meyer, Katrin and Lausser, Florian}, title = {FMS-BERICHTE SOMMERSEMESTER 2022}, editor = {Meier, Hans and Niemetz, Michael and Fuhrmann, Thomas and Reindl, Andrea}, address = {Regensburg}, organization = {Ostbayerische Technische Hochschule Regensburg / Fakult{\"a}t Elektro- und Informationstechnik}, doi = {10.35096/othr/pub-5468}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-54685}, pages = {II, 82}, abstract = {Dieser Bericht entstand im Rahmen der Lehrveranstaltung „Forschungsmethoden und Seminar (FMS)" im Sommersemester 2022 auf Initiative der Studierenden des Masterstudiengangs „Elektro- und Informationstechnik (MEI)". Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuf{\"u}hren. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Ver{\"o}ffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu pr{\"a}sentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinf{\"u}hrung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation f{\"u}r die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualit{\"a}t aufgefundener Fachliteratur, Auswahl geeigneter Materialien f{\"u}r 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 wertsch{\"a}tzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschul{\"o}ffentlicher Pr{\"a}sentation der Ergebnisse • F{\"u}hren m{\"u}ndlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel {\"u}ber noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verf{\"u}gen, lag der w{\"a}hlbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen.}, subject = {Literaturrecherche}, language = {de} } @techreport{BraeuerZwickReifetal., author = {Br{\"a}uer, Armin and Zwick, Christian and Reif, Florian and Kick, Andreas and Albrecht, Manuel and Mayer, Christoph and Baddour, Mahmoud and Stober, Lukas and Kirmeier, Andreas and Griesbeck, Sebastian and Reger, Simon}, title = {FMS-BERICHTE WINTERSEMESTER 2021/2022}, editor = {Meier, Hans and Niemetz, Michael and Fuhrmann, Thomas and Reindl, Andrea}, address = {Regensburg}, doi = {10.35096/othr/pub-5437}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-54371}, pages = {II, 56}, abstract = {Dieser Bericht entstand im Rahmen der Lehrveranstaltung „Forschungsmethoden und Seminar (FMS)" im Wintersemester 2021/22 auf Initiative der Studierenden des Masterstudiengangs „Elektro- und Informationstechnik (MEI)". Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuf{\"u}hren. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Ver{\"o}ffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu pr{\"a}sentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinf{\"u}hrung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation f{\"u}r die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualit{\"a}t aufgefundener Fachliteratur, Auswahl geeigneter Materialien f{\"u}r 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 wertsch{\"a}tzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschul{\"o}ffentlicher Pr{\"a}sentation der Ergebnisse • F{\"u}hren m{\"u}ndlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel {\"u}ber noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verf{\"u}gen, lag der w{\"a}hlbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen.}, subject = {Elektrotechnik}, language = {de} } @inproceedings{RiegerOetjenvandeParetal., author = {Rieger, Anna and Oetjen, Arne and van de Par, Steven and Rabl, Hans-Peter}, title = {Einfluss der Dissonanz auf die Wahrnehmung der Ger{\"a}uschqualit{\"a}t}, series = {Fortschritte der Akustik DAGA 2022: 48. Jahrestagung f{\"u}r Akustik, 21. - 24. M{\"a}rz 2022, Stuttgart und Online}, volume = {48}, booktitle = {Fortschritte der Akustik DAGA 2022: 48. Jahrestagung f{\"u}r Akustik, 21. - 24. M{\"a}rz 2022, Stuttgart und Online}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik e.V.}, address = {Stuttgart}, language = {de} } @article{UhlarHeyderKoenig, author = {Uhlar, Stefan and Heyder, Florian and Koenig, Thomas}, title = {Assessment of two physical tyre models in relation to their NVH performance up to 300 Hz}, series = {Vehicle system dynamics}, volume = {59}, journal = {Vehicle system dynamics}, number = {3}, publisher = {Taylor\&Francis}, doi = {10.1080/00423114.2019.1681475}, pages = {331 -- 351}, abstract = {The prediction of structure-borne noise using numerical methods has a crucial influence during the development process of modern passenger cars. In order to minimise the dynamic forces from the chassis transferred to the body structure, multibody simulation (MBS) can be used. The link between the road surface and the chassis is established by the tyre and its own structural dynamic characteristics. Therefore, it is substantial and the main goal of the present paper to investigate the Noise, Vibration and Harshness (NVH) performance of two commercial physical tyre models available and commonly used in the market. The intention is to point out what kind of results (up-to-date) a user of these structural dynamic tyre models, namely FTire and CDtire/3D, will get with a focus on NVH. The authors strictly follow the established process of how to obtain the fitted tyre property files, as any other user of FTire and CDTire currently does. This process includes a measurement campaign of the real tyre and a subsequent fitting of the tyre property file. The fitting in this case is provided by the tyre model developers themselves, namely cosin and Fraunhofer ITWM. The tyre models are then integrated into the MBS software MSC.Adams where their performance will be assessed based on measured wheel-hub forces in the time and frequency domain up to 300 Hz.}, language = {en} } @incollection{MuehlbauerRablRottengruber, author = {M{\"u}hlbauer, Christian and Rabl, Hans-Peter and Rottengruber, Hermann}, title = {Acoustic Optimization of Mechatronic Direct Injection Systems and Analysis of the Effects on Robustness in System Operation}, series = {SAE International Journal of Advances and Current Practices in Mobility}, volume = {4}, booktitle = {SAE International Journal of Advances and Current Practices in Mobility}, number = {1}, publisher = {SAE International, Warrendale, PA, United States}, issn = {2641-9645}, doi = {10.4271/2021-01-0671}, pages = {68 -- 77}, abstract = {The tightening of the emission legislation and political and social demands for sustainable mobility are forcing the automotive industry to develop complex, high precision mechatronic drive systems. The increasing precision of mechatronic components generally leads to an increase in structural excitation and thus to a rise in noise. The so-called ticking of the fuel injection system has a rather low sound pressure level compared to the residual engine noise. Nevertheless, the impulsive and high frequency noise character leads to a decline concerning the perception of comfort and sound quality. In order to identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed which represents the structure-borne and airborne sound radiation of the stand-alone injection system in a close to series configuration. In this paper, measures for the acoustic optimization of injection systems and their effects on the robustness of the system are discussed. The focus is on engine idling, since at this operating point the ticking of the injectors and high-pressure pump can be perceived most clearly due to the low masking effects of other noise sources. For this purpose, the injection parameters were measured during full engine operation and transferred to the system test bench. By using a special development control unit, it was possible to modify the parameters, quantify their influence on the acoustic behavior and, based on this, define NVH optimized control strategies. For the robustness evaluation of the NVH optimized control strategies, key functions of the injection system were analyzed under varying boundary conditions in system operation on an injection rate test bench.}, language = {en} } @techreport{EmmertGlueckFreilingeretal., author = {Emmert, Michael and Gl{\"u}ck, Sven and Freilinger, Eva and Brandl, Dominik and Schindler, Sebastian and Kaul, Nicolas and Rasp, Franziska and Akstaller, Monika and Wetzel, Daniel and Jupke, Michael and Bodensteiner, Michael and Hohlfeld, Philipp and B{\"o}hm, Kevin and Brem, Theresa and Hammer, Pascal and Singer, Thomas and Karing, Maria and Schneider, Viola and Ostermeier, Tobias}, title = {FMS-Berichte (Mai 2021)}, editor = {Meier, Hans and Niemetz, Michael and Reindl, Andrea}, address = {Regensburg}, doi = {10.35096/othr/pub-1915}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-19155}, pages = {99}, abstract = {Dieser Bericht entstand auf Initiative der Studierenden des 2020 neu gegr{\"u}ndeten Masterstudiengangs „Elektro- und Informationstechnik (MEI)", 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, heranzuf{\"u}hren. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Ver{\"o}ffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu pr{\"a}sentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinf{\"u}hrung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation f{\"u}r die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualit{\"a}t aufgefundener Fachliteratur, Auswahl geeigneter Materialien f{\"u}r 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 wertsch{\"a}tzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschul{\"o}ffentlicher Pr{\"a}sentation der Ergebnisse • F{\"u}hren m{\"u}ndlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel {\"u}ber noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verf{\"u}gen, lag der w{\"a}hlbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen.}, language = {de} } @article{KurzweilScheuerpflug, author = {Kurzweil, Peter and Scheuerpflug, Wolfgang}, title = {State-of-charge monitoring and battery diagnosis of different lithium ion chemistries using impedance spectroscopy}, series = {Batteries}, volume = {7}, journal = {Batteries}, number = {1}, doi = {10.3390/batteries7010017}, pages = {16}, abstract = {For lithium iron phosphate batteries (LFP) in aerospace applications, impedance spectroscopy is applicable in the flat region of the voltage-charge curve. The frequency-dependent pseudocapacitance at 0.15 Hz is presented as useful state-of-charge (SOC) and state-of-health (SOH) indicator. For the same battery type, the prediction error of pseudocapacitance is better than 1\% for a quadratic calibration curve, and less than 36\% for a linear model. An approximately linear correlation between pseudocapacitance and Ah battery capacity is observed as long as overcharge and deep discharge are avoided. We verify the impedance method in comparison to the classical constant-current discharge measurements. In the case of five examined lithium-ion chemistries, the linear trend of impedance and SOC is lost if the slope of the discharge voltage curve versus SOC changes. With nickel manganese cobalt (NMC), high impedance modulus correlates with high SOC above 70\%.}, language = {en} } @misc{AltmannGadererRabl, author = {Altmann, Robert and Gaderer, Matthias and Rabl, Hans-Peter}, title = {Pr{\"u}fstandsuntersuchungen an einem DEUTZ NRMM Motor mit Raps{\"o}lkraftstoff und Optimierung des Betriebs- und Emissionsverhaltens durch statistische Versuchsplanung}, series = {18. Internationaler Fachkongress "Kraftstoffe der Zukunft 2021" - digital \& international vernetzt!, online}, journal = {18. Internationaler Fachkongress "Kraftstoffe der Zukunft 2021" - digital \& international vernetzt!, online}, language = {de} } @article{SteiningerGadererDawoud, author = {Steininger, Peter and Gaderer, Matthias and Dawoud, Belal}, title = {Assessment of the Annual Transmission Heat Loss Reduction of a Refurbished Existing Building with an Advanced Solar Selective Thermal Insulation System}, series = {Sustainability}, volume = {13}, journal = {Sustainability}, number = {13}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/su13137336}, pages = {1 -- 19}, abstract = {A numerical parameter sensitivity analysis of the design parameters of the recently published solar selective thermal insulation system (SATIS) has been carried out to enhance its thermal and optical properties. It turned out that the insulation properties of SATIS can be effectively improved by reducing the length of the glass closure element. Increasing the area share of the light conducting elements (LCEs) and decreasing their length-to-diameter (L/D) ratio were identified as key parameters in order to increase the solar gain. Two SATIS variants were compared with the same wall insulation without SATIS in a yearly energetic performance assessment. The SATIS variant with 10 mm length of the closure element, 44.2\% area share of LCE, as well as front and rear diameters of 12 mm/9 mm shows an 11.8\% lower transmission heat loss over the heating period than the wall insulation without SATIS. A new methodology was developed to enable the implementation of the computed solar gains of SATIS in 1D simulation tools. The result is a radiant heat flow map for integration as a heat source in 1D simulation models. A comparison between the 1D and 3D models of the inside wall heat fluxes showed an integral yearly agreement of 98\%.}, language = {en} } @article{SavelievFetisovChashinetal., author = {Saveliev, Dmitry and Fetisov, Leonid Y. and Chashin, Dmitri V. and Fetisov, Yuri K. and Khon, Anastasia and Shamonin (Chamonine), Mikhail}, title = {Effects of ferromagnetic-material thickness on magnetoelectric voltage transformation in a multiferroic heterostructure}, series = {Smart Materials and Structures}, volume = {30}, journal = {Smart Materials and Structures}, number = {6}, publisher = {IOP PUBLISHING}, doi = {10.1088/1361-665X/abf6c0}, abstract = {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.}, language = {en} } @article{VerezBorriCrespoetal., author = {V{\´e}rez, David and Borri, Emiliano and Crespo, Alicia and Zsembinszki, Gabriel and Dawoud, Belal and Cabeza, Luisa F.}, title = {Experimental Study of a Small-Size Vacuum Insulated Water Tank for Building Applications}, series = {Sustainability}, volume = {13}, journal = {Sustainability}, number = {10}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/su13105329}, pages = {1 -- 11}, abstract = {Insulation of thermal energy storage tanks is fundamental to reduce heat losses and to achieve high energy storage efficiency. Although water tanks were extensively studied in the literature, the enhancement of the insulation quality is often overlooked. The use of vacuum insulation has the potential to significantly reduce heat losses without affecting the dimension of the storage system. This paper shows for the first time the results of the heat losses tests done for a 0.535 m3 water tank for residential building applications built with a double wall vacuum insulation. The different tests show that the rate of heat losses strictly depends on the temperature distribution inside the tank at the beginning of the experiment. Compared to a conventional water tank insulated with conventional materials, the U-value of the lateral surface was reduced by almost three times (from 1.05 W/K·m2 to 0.38 W/K·m2) using vacuum insulation. However, the bottom part, which is usually used to place the support parts and the piping, is the critical design part of those tanks acting as a thermal bridge with the ambient and enhancing heat losses.}, language = {en} } @article{BelyaevaKleppLemmeletal., author = {Belyaeva, Inna A. and Klepp, J{\"u}rgen and Lemmel, Hartmut and Shamonin (Chamonine), Mikhail}, title = {Feasibility of Probing the Filler Restructuring in Magnetoactive Elastomers by Ultra-Small-Angle Neutron Scattering}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {10}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/app11104470}, pages = {1 -- 9}, abstract = {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.}, language = {en} } @article{GamischGadererDawoud, author = {Gamisch, Bernd and Gaderer, Matthias and Dawoud, Belal}, title = {On the Development of Thermochemical Hydrogen Storage: An Experimental Study of the Kinetics of the Redox Reactions under Different Operating Conditions}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {4}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/app11041623}, pages = {1 -- 15}, abstract = {This work aims at investigating the reduction/oxidation (redox) reaction kinetics on iron oxide pellets under different operating conditions of thermochemical hydrogen storage. In order to reduce the iron oxide pellets (90\% Fe2O3, 10\% stabilizing cement), hydrogen (H2) is applied in different concentrations with nitrogen (N2), as a carrier gas, at temperatures between between 700 ∘C and 900 ∘C, thus simulating the charging phase. The discharge phase is triggered by the flow of a mixture out of steam (H2O) and N2 at different concentrations in the same temperature range, resulting in the oxidizing of the previously reduced pellets. All investigations were carried out in a thermo-gravimetric analyzer (TGA) with a flow rate of 250mL/min. To describe the obtained kinetic results, a simplified analytical model, based on the linear driving force model, was developed. The investigated iron oxide pellets showed a stable redox performance of 23.8\% weight reduction/gain, which corresponds to a volumetric storage density of 2.8kWh/(L bulk), also after the 29 performed redox cycles. Recalling that there is no H2 stored during the storage phase but iron, the introduced hydrogen storage technology is deemed very promising for applications in urban areas as day-night or seasonal storage for green hydrogen.}, language = {en} } @article{SternerSpecht, author = {Sterner, Michael and Specht, Michael}, title = {Power-to-Gas and Power-to-X-The History and Results of Developing a New Storage Concept}, series = {Energies}, volume = {14}, journal = {Energies}, number = {20}, publisher = {MDPI}, doi = {10.3390/en14206594}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-26202}, abstract = {Germany's energy transition, known as 'Energiewende', was always very progressive. However, it came technically to a halt at the question of large-scale, seasonal energy storage for wind and solar, which was not available. At the end of the 2000s, we combined our knowledge of both electrical and process engineering, imitated nature by copying photosynthesis and developed Power-to-Gas by combining water electrolysis with CO2-methanation to convert water and CO2 together with wind and solar power to synthetic natural gas. Storing green energy by coupling the electricity with the gas sector using its vast TWh-scale storage facility was the solution for the biggest energy problem of our time. This was the first concept that created the term 'sector coupling' or 'sectoral integration'. We first implemented demo sites, presented our work in research, industry and ministries, and applied it in many macroeconomic studies. It was an initial idea that inspired others to rethink electricity as well as eFuels as an energy source and energy carrier. We developed the concept further to include Power-to-Liquid, Power-to-Chemicals and other ways to 'convert' electricity into molecules and climate-neutral feedstocks, and named it 'Power-to-X'at the beginning of the 2010s.}, language = {en} } @misc{Sterner, author = {Sterner, Michael}, title = {Gas aus einer Gesamtenergieversorgungsperspektive - Warum wir Power-to-X f{\"u}r die Klimaneutralit{\"a}t brauchen}, series = {Kopernikus-Konferenz Projekt "Ensure" (Deutsche Umwelthilfe), 15. April 2021}, journal = {Kopernikus-Konferenz Projekt "Ensure" (Deutsche Umwelthilfe), 15. April 2021}, language = {de} } @unpublished{KaulBoellmannThemaetal., author = {Kaul, Anja and B{\"o}llmann, Andrea and Thema, Martin and Kalb, Larissa and St{\"o}ckl, Richard and Huber, Harald and Sterner, Michael and Bellack, Annett}, title = {Identification of Robust Thermophilic Methanogenic Archaea and Packing Material for High Liquid Hold-Up at Low Volumetric Gas Flow Rates for Use in Trickle-Bed Reactors for Biological Methanation}, series = {SSRN Electronic Journal}, journal = {SSRN Electronic Journal}, doi = {10.2139/ssrn.3940878}, abstract = {he hydrogen gas-to-liquid mass transfer is the limiting factor in biological methanation. In a trickle-bed reactor, mass transfer can be increased by high flow velocities in the liquid phase, by adding a packing material with high liquid hold-up, or by choosing methanogenic archaea with a high methane productivity. This study analyzed various packings and methanogenic strains from a hydrodynamic and microbial perspective. By analyzing twelve pure cultures of thermophilic methanogens for their ability to produce high quality methane and to form biofilms on different packings, strains of Methanothermobacter were found to perform better than thus of the genus Methanothermococcus. Best methane production and adherence was observed on DuraTop®, Bioflow 9, and filter foam. DuraTop® and Bioflow 9 had also a high dynamic liquid hold-up, but the maximum hold-up was determined for expanded clay. The ideal combination for use in the ORBIT-trickle-bed reactor was identified as Methanothermobacter thermoautotrophicus IM5 and DuraTop®.}, language = {en} } @misc{SternerSchumm, author = {Sterner, Michael and Schumm, Leon}, title = {Netzpuffer - Speicher \& Kraftwerke als virtuelle Leitungen f{\"u}r mehr Versorgungssicherheit und EE-Integration in Nord und S{\"u}d}, series = {7. Smart-Grid-Fachtagung WAGO, Hannover, 29. Sept. 2021}, journal = {7. Smart-Grid-Fachtagung WAGO, Hannover, 29. Sept. 2021}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Gr{\"u}ner Wasserstoff - wo wir ihn brauchen f{\"u}r die Klimaneutralit{\"a}t}, series = {Energiewendeforum Wasserstoff (Gr{\"u}ner Strom Label e. V.), Bonn, 21. September 2021}, journal = {Energiewendeforum Wasserstoff (Gr{\"u}ner Strom Label e. V.), Bonn, 21. September 2021}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Wie wird Deutschland klimaneutral? Neue L{\"o}sungen f{\"u}r erneuerbare Energieerzeugung}, series = {Jahreskonferenz der Stiftung Nagelschneider zur Erforschung, M{\"u}nchen, 19.11.2021}, journal = {Jahreskonferenz der Stiftung Nagelschneider zur Erforschung, M{\"u}nchen, 19.11.2021}, address = {M{\"u}nchen}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Power-to-X for Europes Energy Transformation - Booster H2Global}, series = {Hydrogen Online Workshop Conference (Mission Hydrogen), 25.03.2021}, journal = {Hydrogen Online Workshop Conference (Mission Hydrogen), 25.03.2021}, language = {en} } @misc{Sterner, author = {Sterner, Michael}, title = {Technologieausblick Solarstromspeicher}, series = {Innovationsforum Photovoltaik, 18. Oktober 2021, Linz}, journal = {Innovationsforum Photovoltaik, 18. Oktober 2021, Linz}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Die Grenzen des Wasserstoff-Hypes}, series = {1. Mitteldeutscher Wasserstoffkongress, 2. November 2021, Leuna CCE Kulturhaus}, journal = {1. Mitteldeutscher Wasserstoffkongress, 2. November 2021, Leuna CCE Kulturhaus}, language = {de} } @inproceedings{AltmannGebhardTroegeretal., author = {Altmann, Robert and Gebhard, J{\"u}rgen and Troeger, Adrian and Winkler, Markus and T{\"o}pfer, Georg and Remmele, Edgar and Gaderer, Matthias and Rabl, Hans-Peter}, title = {Engine performance and emission analysis of a NRMM CI engine with common rail injection system operated with diesel fuel and rapeseed oil fuel}, series = {Proceedings of the 6th Commercial Vehicle Technology Symposium 2020/2021}, booktitle = {Proceedings of the 6th Commercial Vehicle Technology Symposium 2020/2021}, editor = {Berns, Karsten and Dressler, Klaus and Kalmar, Ralf and Stephan, Nicole and Teutsch, Roman and Thul, Martin}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {978-3-658-29716-9}, doi = {10.1007/978-3-658-29717-6_16}, pages = {231 -- 242}, abstract = {The use of alternative fuels in high-power non-road mobile machinery (NRMM) combustion engines is a possible way to substitute fossil fuel. By using pure vegetable oil fuels, like rapeseed oil fuel (DIN 51605), the greenhouse gases can be reduced effectively. Due to the differences in physical and chemical properties, a modification of the engine control unit calibration is necessary to adapt the working process on the fuel. Without modifications, the engine power output with rapeseed oil fuel is lower than with diesel fuel because of the smaller energy content. By adapting the engine settings, like the injection fuel mass, the power loss can be compensated but it accompanies with a higher fuel consumption. The engine emissions at part load conditions show, that there are benefits in particle emissions by using rapeseed oil at similar NOx emissions. Therefore, a design of experiment setup was initiated on a selected engine operation point to determine the effects of further parameters, like rail pressure, manifold pressure and injection pattern, on the process and to see the potential of an optimized calibration.}, language = {en} } @inproceedings{ButtnerAlonsoVillaBohigasBoladerasetal., author = {Buttner, Johannes and Alonso-Villa, Cristina and Bohigas Boladeras, Pere and Kucera, Markus and Waas, Thomas}, title = {The Need for New Software Architectures for Next-generation Vehicle}, series = {Proceedings of the 5th International E-Conference on Advances in Engineering, Technology and Management (ICETM 2021)}, booktitle = {Proceedings of the 5th International E-Conference on Advances in Engineering, Technology and Management (ICETM 2021)}, isbn = {978-1-63248-192-4}, pages = {58 -- 61}, abstract = {Assuming that future connected cars with automated driving functions will require even more computing power and communication bandwidth, the current network infrastructure as well as the existing individualized control units are not a profitable option for such vehicles. In addition, changing user expectations demand flexible architectural patterns and upgradeability of software components without the need to visit the workshop. However, the current statically developed and configured ECU architecture does not offer any practicable possibilities for this. For these reasons, the research for a new dynamic and flexible architecture is necessary. This new type of system architecture is expected to meet future requirements in terms of space, cost, performance, energy efficiency and number of required computing units in the vehicle, which will arise as a result of the implementation/inclusion of new automated driving functionalities, and due to the changes in user expectations. Solutions to this issue can be found in the field of enterprise IT (cluster computing), in which technologies such as Ethernet, container-based virtualization and flexible software architectures have proven themselves to be very efficient for years. Relevant infrastructures, for example from cloud computing providers, have commonly been used in high-performance or high-availability applications. Thus, in the research project A 3F has been investigated which of these concepts and methods can be applied to modern vehicle system architectures. One of the main goals is to assess the synergy potential of the two sectors, information technology and automotive industry, which to date have very different orientations. However, this synergy is expected to grow strongly in the course of the developments mentioned above. In the following pages, the necessary changes related to hardware and software will be discussed briefly und will be compared to concepts and possible solutions from the IT world.}, language = {en} } @inproceedings{MuehlbauerRablRottengruber, author = {M{\"u}hlbauer, Christian and Rabl, Hans-Peter and Rottengruber, Hermann}, title = {Akustische Optimierung von mechatronischen Direkteinspritzsystemen und Analyse der Auswirkungen auf die Robustheit im Systembetrieb}, series = {Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband}, volume = {11}, booktitle = {Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband}, publisher = {Otto-von-Guericke-Universit{\"a}t}, address = {Magdeburg}, doi = {10.25673/36611}, pages = {32 -- 51}, abstract = {The tightening of the emission legislation and political and social demands for sustainable mobility are forcing the automotive industry to develop complex, high precision mechatronic drive systems. The increasing precision of mechatronic components generally leads to an increase in structural excitation and thus to a rise in noise. The socalled ticking of the fuel injection system has a rather low sound pressure level compared to the residual engine noise. Nevertheless, the impulsive and high frequency noise character leads to a decline concerning the perception of comfort and sound quality. In order to identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed which represents the structureborne and airborne sound radiation of the stand-alone injection system in a close to series configuration. In this paper, measures for the acoustic optimization of injection systems and their effects on the robustness of the system are discussed. The focus is on engine idling, since at this operating point the ticking of the injectors and the high-pressure pump can be perceived most clearly due to the low masking effects of other noise sources. For this purpose, the injection parameters were measured during full engine operation and transferred to the system test bench. By using a special development control unit, it was possible to modify the parameters, quantify their influence on the acoustic behavior and, based on this, define NVH optimized control strategies. For the robustness evaluation of the NVH optimized control strategies, key functions of the injection system were analyzed under varying boundary conditions in system operation on an injection rate test bench.}, language = {de} } @inproceedings{SchneiderMuehlbauerSittletal., author = {Schneider, Sebastian and M{\"u}hlbauer, Christian and Sittl, Christopher and Rottengruber, Hermann and Rabl, Hans-Peter and Wagner, Marcus and Verhey, Jesko L.}, title = {Tickerger{\"a}uschanalyse an einem Otto-DI-Motor mittels empirischer Bewertungsformel}, series = {Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband}, booktitle = {Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband}, editor = {Rottengruber, Hermann and Luft, Tommy and Schneider, Sebastian}, publisher = {Otto-von-Guericke-Universit{\"a}t}, address = {Magdeburg}, isbn = {978-3-948749-02-6}, doi = {10.25673/36611}, pages = {65 -- 86}, abstract = {Beim Kauf eines Pkw wird der akustische Qualit{\"a}tseindruck eines Fahrzeugantriebstrangs stetig relevanter. Die wahrgenommene Ger{\"a}uschqualit{\"a}t des Motoraggregates nimmt hierbei eine Schl{\"u}sselrolle ein. Aufgrund der Auspr{\"a}gung einzelner St{\"o}rger{\"a}usche wird jene Ger{\"a}uschqualit{\"a}t negativ beeinflusst. Diese als unangenehm empfundenen Ger{\"a}uschkomponenten gilt es im Rahmen der Fahrzeugentwicklung weiter zu reduzieren, wobei die Identifikation und Bewertung st{\"o}render Ger{\"a}uschanteile am Motorgesamtger{\"a}usch Voraussetzungen f{\"u}r eine effektive Akustikoptimierung sind. Vor allem das impulshafte Tickerger{\"a}usch wird bei Otto-DI-Motoren als besonders l{\"a}stig eingestuft, weswegen dieser Beitrag darauf abzielt, die tickernden Ger{\"a}uschanteile aus dem Gesamtger{\"a}usch zu analysieren und zu bewerten. Hierzu wurde eine empirische Formel entwickelt, welche die tickernden Ger{\"a}uschanteile in ihrer Intensit{\"a}t in Grenzen einstufen kann. Diese ist rein empfindungsbasiert und besteht aus der Impulshaftigkeit, der Lautheit sowie der Sch{\"a}rfe des Motorgesamtger{\"a}usches. Wie auch bei anderen psychoakustischen Bewertungsskalen wurde die Benotung von 1 (sehr tickernd) bis 10 (nicht tickernd) vorgenommen. Anhand von H{\"o}rversuchen mithilfe einer Expertenjury konnte die Tickerger{\"a}uschbewertungsformel anschließend verifiziert werden. Hiernach kann pr{\"a}zise ausgesagt werden, in welchen Motorkennfeldbereichen das Tickerger{\"a}usch die Angenehmheit des Motorgesamtger{\"a}usches untergr{\"a}bt.}, language = {de} } @inproceedings{BruecklWildfeuerSchaechinger, author = {Br{\"u}ckl, Oliver and Wildfeuer, M. and Sch{\"a}chinger, J.}, title = {Systemdienstleistungen durch Biogasanlagen}, series = {Biogas in der Landwirtschaft - Stand und Perspektiven: 7. FNR/KTBL-Onlinetagung 29.-30.09.2021, Darmstadt}, booktitle = {Biogas in der Landwirtschaft - Stand und Perspektiven: 7. FNR/KTBL-Onlinetagung 29.-30.09.2021, Darmstadt}, address = {Darmstadt}, isbn = {978-3-945088-83-8}, pages = {92 -- 101}, subject = {Biogasanlage}, language = {de} } @inproceedings{JupkeReindlMeieretal., author = {Jupke, Michael and Reindl, Andrea and Meier, Hans and Niemetz, Michael}, title = {Bidirectional DC-DC Converter with Digital Droop Parameterization}, series = {26th 2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021 Pilsen, Czech Republic}, booktitle = {26th 2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021 Pilsen, Czech Republic}, editor = {Pinker, Jiř{\´i}}, publisher = {Institute of Electrical and Electronics Engineers}, isbn = {978-80-261-0972-3}, doi = {10.23919/AE51540.2021.9542920}, pages = {1 -- 6}, abstract = {The key for decentralized battery systems is a robust and communication-less control strategy for autonomous power sharing of parallel-connected DC-DC converters. Battery systems improve the reliability and quality of power supply in renewable energy systems and enable power supply for off-grid, mobile applications, including islanded grids, home storage, and electric vehicles. In many cases, components with different electrical properties require different voltage levels. An adaptation is consequently essential and is normally implemented in DC grids for the batteries via bidirectional DC-DC converters. The power flow in both directions can thus be ensured. To achieve a power distribution in parallel connected DC-DC converters, a droop control in the form of a virtual internal resistor can be used. This paper presents a novel approach of a DC-DC converter with a digitally parameterizable droop resistor, whose voltage regulation is based on an analog operational amplifier circuit to ensure low delays and robustness. The droop resistor is adjusted with a microcontroller, which offers the possibility to apply a higher-level control for load sharing via an interface. Mathematical correlations are used to clearly define the parameters of the control. Furthermore, the circuit was completely simulated and tested in the hardware setup. The shown results verify the functionality and indicate only minor deviations. Therefore, this circuit is important for future use in distributed battery systems.}, language = {en} } @inproceedings{ReindlSingerMeieretal., author = {Reindl, Andrea and Singer, Thomas and Meier, Hans and Niemetz, Michael and Park, Sangyoung}, title = {Framework to Test DC-DC Converters Developed for a Decentralized Battery Management System}, series = {2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021, Pilsen, Czech Republic}, booktitle = {2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021, Pilsen, Czech Republic}, publisher = {IEEE}, doi = {10.23919/AE51540.2021.9542882}, pages = {1 -- 6}, abstract = {DC- DC converters control the power flow and thus the power distribution between the components on different voltage levels. They are essential for (dis)charging batteries and influence the safety and stability of the entire battery management system (BMS). Therefore, testing the functionality and the reliability of DC-DC converters is crucial. This is especially true for decentralized battery management systems (DBMS), where multiple nodes communicate to collectively control the system. The used DC-DC converters are modified to parameterize them during operation via microcontroller interfaces. Integrating the communication into the control loop requires an analysis of the control behavior due to additional delays. Therefore, this paper proposes a framework to test DC-DC converters considering the control and communication perspectives. The response time, the control accuracy and stability of these DC-DC converters, e.g., under continuous and abrupt load changes, are measured in automated tests. The dedicated software framework simulates the DBMS and stimulates the hardware components (e.g. electronic loads, data acquisition) via respective interfaces (CAN, RS232). This allows the test of various DC-DC converters with flexibly adaptable load and power generation profiles. An initial application validates the test framework by verifying the aforementioned aspects and thus the applicability of a DC-DC converter within the DBMS.}, language = {en} } @inproceedings{ReindlMeierNiemetzetal., author = {Reindl, Andrea and Meier, Hans and Niemetz, Michael and Park, Sangyoung}, title = {Decentralized Battery Management System with Customized Hardware Components}, series = {IEEE 19th Student Conference on Research and Development (SCOReD), Sustainable Engineering and Technology towards Industry Revolution: 23-25 Nov. 2021, Kota Kinabalu, Malaysia}, booktitle = {IEEE 19th Student Conference on Research and Development (SCOReD), Sustainable Engineering and Technology towards Industry Revolution: 23-25 Nov. 2021, Kota Kinabalu, Malaysia}, publisher = {IEEE}, doi = {10.1109/SCOReD53546.2021.9652737}, pages = {350 -- 355}, abstract = {With an increasing number of sold electric vehicles (EVs), a large number of used batteries will be at disposal. How to deal with these resources is one of the major challenges in reducing the environmental impact of batteries throughout their entire life cycle. Heterogeneous cell parameters due to the different usage histories are a challenge for second-life use. The effort and cost of remanufacturing required to test and assemble a new battery pack is a further concern. Systems that combine battery packs/modules without full reassembly offer advantages such as cost and reusability. A decentralized battery management system (DBMS) provides a suitable architecture for such systems involving different types of batteries. In this paper, an architecture for a decentralized, battery state-dependent control is shown. The proposed DBMS supports various types of batteries, is scalable and flexibly adaptable for a wide range of applications. Despite the significant advantages, there are increased requirements to meet for the hardware implementation and the applied control strategies. Therefore, the necessary hardware components and their requirements are described and the hardware implementations are provided.}, language = {en} } @inproceedings{SchubertLeeOoi, author = {Schubert, Martin J. W. and Lee, Wai-Kong and Ooi, Boon Yaik}, title = {Quantization and Sampling Effects in Fast Digitally Controlled Switch-Mode DC/DC Buck Converters}, series = {2021 IEEE Industrial Electronics and Applications Conference (IEACon): 22.11.2021 - 23.11.2021, Penang, Malaysia}, booktitle = {2021 IEEE Industrial Electronics and Applications Conference (IEACon): 22.11.2021 - 23.11.2021, Penang, Malaysia}, publisher = {IEEE}, isbn = {978-1-7281-9253-6}, doi = {10.1109/IEACon51066.2021.9654272}, pages = {56 -- 61}, abstract = {Software-defined control of DC/DC switch mode power converters features unequaled flexibility compared to analog control. For fast switching converters as recently used for low power applications, digital control may cause steady-state oscillations known as limit cycles. This effect based on a quantized duty cycle is compared to other aberrations such as output ripple voltage, which is inherent to any pulse-width modulator. A distinction is made between DC and AC errors. The latter are divided into synchronous and asynchronous output voltage disturbances. Synchronous AC errors are composed of the switching frequency and its harmonics.}, language = {en} } @inproceedings{CroceDiamantidisSykora, author = {Croce, Valeria and Diamantidis, Dimitris and S{\´y}kora, Miroslav}, title = {Planning post earthquake surveys: assessments and reconstruction of small historical centres}, series = {1st IABSE Online Symposium 2020, Synergy of culture and civil engineering - history and challenges: Wrocław, Poland, 7-9 October 2020, Proceedings}, booktitle = {1st IABSE Online Symposium 2020, Synergy of culture and civil engineering - history and challenges: Wrocław, Poland, 7-9 October 2020, Proceedings}, editor = {Bien, Jan}, publisher = {Curran Associates Inc}, address = {Red Hook, NY}, isbn = {978-1-7138-2387-2}, pages = {332 -- 339}, abstract = {The contribution presents a methodological procedure for the management and planning of interventions after earthquake events in small historic centres. Reference is made to the case study of Castelluccio di Norcia, a village in the Apennine Mountains affected by the seismic sequence that hit Central Italy in 2016. The earthquake risk of the area and the damaging events of 2016 are critically reviewed. The implementation of cognitive analysis and the application of advanced survey techniques involving the use of nmanned Aerial Vehicles (UAVs) for the purposes of emergency management and monitoring of damaged areas are analysed. The outcomes, combined with the direct involvement of the local population, represent a complete and integrated approach allowing the definition of a) possible intervention strategies, b) related decision criteria and c) practical recommendations for the reconstruction and regeneration of Castelluccio, and, in general, of small historic centres damaged by catastrophic events.}, language = {en} } @inproceedings{GrabRauchGoetzetal., author = {Grab, Robin and Rauch, Johannes and G{\"o}tz, Rebekka and Br{\"u}ckl, Oliver and Eichner, Stefan and Engel, Bernd}, title = {Q-Dynamik: Blindleistungsstellgeschwindigkeiten im Verteilnetz}, series = {Zuk{\"u}nftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021, Tagungsunterlagen}, booktitle = {Zuk{\"u}nftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021, Tagungsunterlagen}, publisher = {Conexio-PSE GmbH}, address = {Pforzheim}, isbn = {978-3-948176-12-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-58762}, pages = {46 -- 55}, abstract = {Mit der Energiewende geht eine starke Dezentralisierung der Energieeinspeisung einher. So sind im Deutschland des Jahres 2020 rund 31.000 Windenergieanlagen (WEA) in Betrieb, w{\"a}hrend 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 R{\"u}ckbau konventioneller Großkraftwerke, welche dem {\"U}bertragungsnetz bisher als Blindleistungsquellen zur Verf{\"u}gung standen, bedarf es einer Untersuchung mit der Fragestellung, in welchem Maß die neue Erzeugungslandschaft auch in diesem Feld als Ersatz dienen kann. Ein m{\"o}gliches Hindernis f{\"u}r einen breitangelegten Einsatz von DER zu Zwecken des spannungsebenen{\"u}bergreifenden Blindleistungsmanagements ist mangelndes Wissen {\"u}ber die Regeldynamik dieser verteilten Blindleistungsquellen. {\"U}bertragungs- und Verteilnetzbetreiber, die DER aktiv f{\"u}r Blindleistungsausgleich oder statische Spannungsregelung einsetzen, geben in der Regel ihre Blindleistungsanforderungen in kleineren Stufen mit erheblichen Latenzzeiten zwischen zwei Schritten weiter. Bef{\"u}rchtet wird, dass schnellere Spr{\"u}nge in der Blindleistungsvorgabe zu instabilen Betriebszust{\"a}nden oder anderweitigen Fehlfunktionen im Netz f{\"u}hren k{\"o}nnen. Eine genauere Kenntnis der dynamischen F{\"a}higkeiten vorhandener Blindleistungsquellen sowie der Auswirkungen auf die Netzstabilit{\"a}t und den Netzschutz k{\"o}nnte dazu beitragen, die Geschwindigkeit der Blindleistungsbereitstellung zu optimieren und somit tempor{\"a}re Spannungsschwankungen und -verluste zu minimieren und die Spannungsstabilit{\"a}t insgesamt zu verbessern. Durch eine entsprechende Regelungs- und Einsatzstrategie kann ein optimales Zusammenspiel der verschiedenen Technologien zur Deckung der Blindleistungsbedarfe f{\"u}r unterschiedliche Zeitbereiche erzielt werden. Hierf{\"u}r 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 vollst{\"a}ndig aufzuf{\"u}hren, werden zun{\"a}chst typische Kommunikationszeiten f{\"u}r die {\"U}bermittlung von Sollwerten diskutiert. Anschließend werden Untersuchungen zu theoretischen und praktischen Reaktionszeiten verschiedener Blindleistungsquellen vorgestellt. Daf{\"u}r werden verschiedene Technologien wie Umrichter f{\"u}r 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.}, language = {de} } @misc{Hartweg, type = {Master Thesis}, author = {Hartweg, Johanna}, title = {Analyse des Einflusses verschiedener Arbeitspunkte auf die wirkleistungsabh{\"a}ngige Spannungssensitivit{\"a}t an einem Mittelspannungsnetzknoten}, address = {Regensburg}, doi = {10.35096/othr/pub-5564}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55648}, school = {Ostbayerische Technische Hochschule Regensburg}, pages = {76}, abstract = {Im Rahmen dieser Arbeit erfolgt die Untersuchung der wirkleistungsabh{\"a}ngigen Spannungssensitivit{\"a}t an den Knoten eines Mittelspannungsnetzstranges. Hierf{\"u}r wird eine Reihe von Arbeitspunkten durch die Variation der Wirkleistungsentnahmen bzw. Einspeisungen an den Netzknoten sowie des Verschiebungsfaktors und der Spannungssollwertvorgabe am Bilanzknoten erzeugt. Die Ergebnisse zeigen eine direkte Abh{\"a}ngigkeit von der Spannung des untersuchten Netzknotens. Hierbei steigt die Sensitivit{\"a}t bei fallenden Spannungswerten. Diese k{\"o}nnen sowohl durch Wirk- und Blindleistungsbelastungen als auch durch eine ver{\"a}nderte Referenzspannung am Umspannwerk bedingt werden. Dar{\"u}ber hinaus liegt eine Beeinflussung durch die Wirkleistungsbelastung und deren Verteilung {\"u}ber den Netzstrang hinweg vor. Je h{\"o}her die Belastung der Leitung bis zum Knoten der Flexibilit{\"a}t ausf{\"a}llt sowie je st{\"a}rker sich die Last hin zu diesem Punkt verlagert, desto h{\"o}her ist die Sensitivit{\"a}t. Dies gilt ebenfalls f{\"u}r Arbeitspunkte mit gleichbleibender Spannung in den betrachteten Knoten. Des Weiteren wird die Anpassung eines multiplen linearen Regressionsmodells vorgenommen. Dieses erm{\"o}glicht eine Absch{\"a}tzung der Sensitivit{\"a}tswerte durch die Kenntnis einiger, die Belastungssituation des Netzes bestimmender Parameter.}, language = {de} } @techreport{GerhardsWeberKlafkaetal., author = {Gerhards, Christoph and Weber, Urban and Klafka, Peter and Golla, Stefan and Hagedorn, Gregor and Baumann, Franz and Brendel, Heiko and Breyer, Christian and Clausen, Jens and Creutzig, Felix and Daub, Claus-Heinrich and Helgenberger, Sebastian and Hentschel, Karl-Martin and von Hirschhausen, Christian and Jordan, Ulrike and Kemfert, Claudia and Krause, Harald and Linow, Sven and Oei, Pao-Yu and Pehnt, Martin and Pfennig, Andreas and Pr{\"a}ger, Fabian and Quaschning, Volker and Schneider, Jens and Spindler, Uli and Stelzer, Volker and Sterner, Michael and Wagener-Lohse, Georg and Weinsziehr, Theresa}, title = {Klimavertr{\"a}gliche Energieversorgung f{\"u}r Deutschland - 16 Orientierungspunkte}, series = {Diskussionsbeitr{\"a}ge der Scinetists for Future ; 7}, journal = {Diskussionsbeitr{\"a}ge der Scinetists for Future ; 7}, doi = {10.5281/zenodo.4409334}, abstract = {Als fairer Beitrag Deutschlands zur Einhaltung der globalen 1,5-Grad-Grenze werden 16 Orientierungspunkte f{\"u}r eine klimavertr{\"a}gliche Energieversorgung vorgestellt. Es wird davon ausgegangen, dass hierf{\"u}r die deutschen energiebedingten CO2-Emissio­nen in etwa 15 Jahren weitgehend auf Null sinken m{\"u}ssen. Energieeinsparung hilft, den notwendigen Ausbau von regenerativen Erzeugungskapazit{\"a}ten zu verringern. Der Verkehrssektor kann ebenso wie die Bereiche Prozess- und Geb{\"a}udew{\"a}rme hier­zu wesentlich beitragen. Die Kernenergie ist mit großen Risiken belastet und kann nicht hinreichend schnell aufgebaut werden. Biomasse in Form von Energie­pflan­zen zu nutzen, ist ineffizient und steht im Konflikt mit anderen Arten der Land­nut­zung. Importe klimaneutral erzeugter Energietr{\"a}ger in sehr großem Umfang er­for­dern extrem große Investitionen im Ausland. Sie sind eine ungesicherte Option auf die Zukunft. Entscheidend ist daher der ausreichend schnelle Ausbau von Photovoltaik (PV) und Wind­kraft in Deutschland. Sch{\"a}tzungsweise kann der Elektrizit{\"a}tsbedarf im Jahr 2030 z.B. durch den Ausbau auf ca. 350 GW PV und ca. 150 GW Windkraft nahe­zu voll­st{\"a}ndig regenerativ gedeckt werden. Damit ließe sich eine zum großen Teil elek­tri­fizierte Mobilit{\"a}t und W{\"a}rmeversorgung betreiben und ein Teil des ben{\"o}­tig­ten "gr{\"u}­nen" Wasserstoffs in Deutschland bereitstellen. Hierf{\"u}r ist ein j{\"a}hr­licher Zu­bau von durchschnittlich ca. 30 GW PV und ca. 9 GW Windkraft n{\"o}tig. Dies ist ca. sechs- (PV) bzw. dreimal (Wind) so hoch wie bisher vorgesehen und verlangt eine ge­sell­schaft­liche Kraftanstrengung. Ein weiter verz{\"o}gerter Ausbau m{\"u}sste mit noch deut­lich gr{\"o}ßeren gesellschaftlichen Anstrengungen f{\"u}r drastische Energieeinspa­run­gen oder Importe erneuerbarer Energie ausgeglichen werden. Insgesamt k{\"o}nnte dies noch deutlich schwieriger zu realisieren sein, als ein ambitionierter Ausbau. Da der Auf­bau der Kapazit{\"a}ten mehrere Jahre erfordert, ist es m{\"o}glich nachzusteuern, z. B. wenn erkennbar wird, dass sich ein ausreichend großer globaler Markt f{\"u}r Importe ent­wi­ckelt. Bis dahin ist es aus Verantwortung gegen­{\"u}ber der Zukunft und im Sinne des Pariser Vertrages empfehlenswert, die hier genannten Ausbauziele zu verfol­gen. Gr{\"u}ner, also aus erneuerbaren Energien hergestellter Wasserstoff und daraus abge­lei­tete Syntheseprodukte sind f{\"u}r die Dekarbonisierung von Industrieprozessen, den Flug- und Schiffsverkehr sowie f{\"u}r die Absicherung der Energieversorgung bei Dun­kel­flauten n{\"o}tig. Ohne die genannten Ausbauziele f{\"u}r Wind und Solar noch drastisch weiter zu erh{\"o}hen, stehen diese Produkte f{\"u}r Straßenverkehr und W{\"a}rmeversor­gung jedoch nicht in ausreichenden Mengen zur Verf{\"u}gung. Techniken zum Aus­gleich zwischen Elektrizit{\"a}tsangebot und -nachfrage sind verf{\"u}gbar und sollten recht­zeitig auf- bzw. ausgebaut werden. Hierzu geh{\"o}ren: Stromaustausch mit den Nach­barl{\"a}ndern, Flexibilisierung des Verbrauchs und Energiespeicherung. F{\"u}r deren Inte­gration sowie den Ausbau der Netze sollten z{\"u}gig verbesserte rechtliche Rah­men­bedingungen geschaffen werden. Die Kosten eines klimavertr{\"a}glichen Energiesystems sind mittel- bis langfristig nicht h{\"o}­her als im derzeitigen System. Gleichzeitig entstehen Arbeitspl{\"a}tze und Export­chan­cen durch Aufbau, Betrieb und Wartung einer regenerativen Energieversorgung in Deutschland und die energetische Geb{\"a}udesanierung. Die politischen Rahmenbe­din­gungen entscheiden, ob eine klimavertr{\"a}gliche Energieversorgung Deutschlands ge­lingt.}, language = {de} } @inproceedings{GoetzRauchBrueckl, author = {Goetz, Rebecca and Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Techno-economic analysis of reactive power sources}, series = {NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: Hamburg, 13.-14. September 2021}, booktitle = {NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: Hamburg, 13.-14. September 2021}, editor = {Schulz, Detlef}, publisher = {VDE-Verlag}, isbn = {978-3-8007-5651-3}, pages = {286 -- 291}, abstract = {This paper presents different options to provide reactive power in electricity grid systems. Since conventional power plants are being phased out and the reactive power demand tends to increase, alternative technologies are needed to cover it. reactive power sources are being defined and specified in this submission. A technical evaluation and an economic analysis of selected reactive power sources are carried out, based on interviews with manufacturers and operators. As well a multifactorial techno-economic comparison of the evaluated reactive power sources is presented. The technical analysis addresses reactive power control-ranges, stochastic parameters, lifespans, electrical losses and dynamics of re-active power sources. It states that power electronics allow faster setpoint changes than mechanical technologies can achieve, but at the same time this is associated with the highest electrical losses of the reactive power sources considered here. Considering the economic analysis, relative investment costs per reactive power of conventional compensation systems turn out to be the most cost-efficient. With regard to the multifactorial techno-economic comparison, it is im-portant not only to standardize on reactive power that can be provided, but also to include the additional system-relevant properties of technologies in the evaluation as well as the costs in operation.}, language = {en} } @techreport{SternerSchummRanketal., author = {Sterner, Michael and Schumm, Leon and Rank, Daniel and Hofrichter, Andreas}, title = {Intelligente Netzpuffer : Abschlussbericht (24.01.2021)}, language = {de} } @inproceedings{SippenauerBruecklHenneke, author = {Sippenauer, Thomas and Br{\"u}ckl, Oliver and Henneke, Markus}, title = {Verankerung von Flexibilit{\"a}t in der Netzplanung}, series = {Zuk{\"u}nftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021}, booktitle = {Zuk{\"u}nftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021}, publisher = {Conexio GmbH}, address = {Pforzheim}, isbn = {978-3-948176-12-9}, doi = {10.35096/othr/pub-5563}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55632}, pages = {79 -- 92}, abstract = {Die Energiewende f{\"u}hrt zu einem steigenden Zubau erneuerbarer Energieerzeugungsanlagen im Verteilungsnetz. Ebenso ist mit einem verst{\"a}rkten Zuwachs der Elektromobilit{\"a}t zu rechnen, der zu einer weiteren Ausreizung der zul{\"a}ssigen Spannungsbereiche und Leitungsauslastungen beitragen kann. Um die Aufnahmef{\"a}higkeit des Verteilungsnetzes zu erh{\"o}hen, wurden in der Vergangenheit verschiedene L{\"o}sungen entwickelt und etabliert. Ein zus{\"a}tzlicher Baustein zur Behebung von Netzengp{\"a}ssen und Spannungsproblemen sind zeitliche Verlagerungen von Einspeisungen und Verbrauchslasten in der Mittelspannungsebene. Diese sogenannten Flexibilit{\"a}tsmaßnahmen sind derzeit noch nicht Stand der Technik. Um einen hohen Nutzen stiften zu k{\"o}nnen, indem sie zu einer effizienten Einsparung an Asset beitragen, m{\"u}ssen sie in der Netzplanung abbildbar gemacht werden. Dazu sind einerseits geeignete technische und zuverl{\"a}ssigkeitstheoretische Anforderungen an die Flexibilit{\"a}tsmaßnahmen herauszuarbeiten, um eine m{\"o}glichst hohe Gesamteffizienz bei Netz- und Anlagenbetreibern zu erzielen und andererseits ein Verfahren zu finden, mit dem Manipulationsm{\"o}glichkeiten (INC-DEC-Gaming) ausgeschlossen bzw. geringgehalten werden k{\"o}nnen.}, language = {de} } @techreport{NeidhartLerchWiesingeretal., author = {Neidhart, Thomas and Lerch, Maximilian and Wiesinger, Doris and Zrenner, Louis}, title = {Kompakte {\"U}bertragungsleitungen f{\"u}r hohe Gleichspannungen: Langzeituntersuchungen an einer erdverlegten Versuchsanlage}, doi = {10.35096/othr/pub-2173}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-21730}, pages = {62, 58}, abstract = {Durch den Ausstieg aus der Verstromung fossiler Energietr{\"a}ger und der daraus resultierenden dezentralen Stromerzeugung ist ein Aus- bzw. Umbau des deutschen {\"U}bertragungsnetzes erforderlich. Weil aus der dezentralen Energieerzeugung große Trassenl{\"a}ngen resultieren, welche bei Wechselstrom zu Blindleistungsproblematiken f{\"u}hren, wird dort vermehrt auf Hochspannungs-Gleichstrom-{\"U}bertragung zur{\"u}ckgegriffen. Im Rahmen des Forschungsprojekts DC CTL DBI (direct current compact transmission line - directly buried investigastions) wurde ein gasisolierte HG{\"U}-Leiter (GIL) erdverlegt und bei st{\"a}ndigem Monitoring {\"u}ber umfangreiche Sensorik einem Langzeitversuch unterzogen. Anstelle einer klassischen Sandbettung kam ein zeitweise fließf{\"a}higer, selbstverdichtender Verf{\"u}llbaustoff (ZFSV) zum Einsatz. Somit k{\"o}nnen Sch{\"a}den an der {\"U}bertragungsleitung infolge Verdichtungsaufwand vermieden und gleichzeitig bessere Bodeneigenschaften hinsichtlich der W{\"a}rme- und Wassertransportprozesse erreicht werden.}, language = {de} } @inproceedings{GrauvoglStauderHopfenspergeretal., author = {Grauvogl, Dominik and Stauder, Peter and Hopfensperger, Bernhard and Gerling, Dieter}, title = {Multiphysics Design of a Wound Field Synchronous Machine with Magnetic Asymmetry}, series = {Proceedings of the 2021 IEEE International Electric Machines \& Drives Conference (IEMDC): 17-20 May 2021, Hartford, CT, USA}, booktitle = {Proceedings of the 2021 IEEE International Electric Machines \& Drives Conference (IEMDC): 17-20 May 2021, Hartford, CT, USA}, doi = {10.1109/IEMDC47953.2021.9449564}, abstract = {In this paper a multiphysics development method is used for designing a novel wound field synchronous machine of the future generation of high voltage traction drives. This method covers the domains of electromagnetics, the mechanical strength, thermal behavior and the magnetic noise. It is shown that the proposed novel asymmetric design with a circular flux barrier in combination with an asymmetric pole offset is fulfilling the requirements according to performance and torque ripple. A fatigue strength rotor mechanic concept is included. A hybrid cooling concept consisting of a water jacket cooled stator and air cooled rotor ensures the needed continuous power. Unacceptable noise levels are excluded by investigating the equivalent radiated power (ERP) level due to radial forces in the air gap. Finally, the multi-physical workflow resulted in a fully developed component with a high degree of maturity.}, language = {en} } @inproceedings{GrauvoglKrabinskiStauderetal., author = {Grauvogl, Dominik and Krabinski, Jeffrey and Stauder, Peter and Hopfensperger, Bernhard and Gerling, Dieter}, title = {NVH Comparison of a Novel Wound Field Synchronous Machine with Magnetic Asymmetry with a PSM for a HV Electric Drive}, series = {2021 JSAE Annual Congress (Spring) Proceedings; online meeting (No.76-21)}, booktitle = {2021 JSAE Annual Congress (Spring) Proceedings; online meeting (No.76-21)}, publisher = {JSAE}, abstract = {This paper shows how magnetic noises can be reduced with a wound field synchronous machine (WFSM) with magnetic asymmetry compared to a permanent magnet synchronous machine (PSM), operating at base speed range and full load. In order to reproduce a real noise behavior, the two rotor types are operated in a complete electric drive unit (EDU) consisting of an electric motor, gearbox, inverter and overall housing. In the concept study, the noise characteristics of the two electric machines is evaluated and compared via mechanical finite element method (FEM) simulations using the equivalent radiated power (ERP) level and Campbell diagrams. Furthermore, it is shown that critical frequency orders can already be identified by the analysis of the magnetic force density from the electromagnetic design without computationally intensive ERP calculations. In this context, the ERP investigations have shown that the unique feature of the magnetically asymmetric WFSM is the reduction of the slot harmonics. At the current state of the art, the slot harmonics can only be reduced with a rotor skewing. The disadvantage of this is a reduction in performance and a more expensive production. It is also remarkable that the magnetic asymmetry reduces the slot harmonics more than the rotor skewing in the PSM. In addition, both machines are still considered with a short-pitched stator winding to optimize the overall noise level by reducing the 24th frequency order.}, subject = {Elektroantrieb}, language = {en} } @inproceedings{SteiningerGadererDawoud, author = {Steininger, Peter and Gaderer, Matthias and Dawoud, Belal}, title = {Transient performance of a solar selective thermal insulation system}, series = {16th Advanced Building Skins Conference \& Expo, 21 - 22/10/2021, Bern, Switzerland}, booktitle = {16th Advanced Building Skins Conference \& Expo, 21 - 22/10/2021, Bern, Switzerland}, publisher = {Advanced Buidling Skins GmbH}, abstract = {A prototype of a thermal insulation system to offer high selectivity of the solar gain regarding the solar incidence angle (SATIS) was applied to a typical solid brick masonry for existing buildings in Germany. Light conducting elements (LCEs) inclined at 19 ° were incorporated in SATIS, which equals the average solar noon angle in southern Germany during winter. The entire wall construction was experimentally investigated in a differential climatic chamber test bench at four different irradiation angles according to a dynamic test procedure. In addition, a conventional wall construction (CWC) has been measured. At SATIS' design angle of 19 °, the SATIS wall construction shows a solar gain (SG) of 394.5 Wh/m², while the SG of the CWC amounts to only 25.4 Wh/m². The validated transient model of the SATIS wall construction showed that, at the end of the irradiation period of the dynamic test procedure (8 h), the solar heat penetrates to a depth of 253 mm and 111 mm inside the 385 mm thick brick wall masonry at the irradiation angles of 19 ° and 50 °, respectively. During the same time, the stored solar energy at 50 ° amounts to only 24.4 \% of that stored at 19 °.}, language = {en} } @misc{Heberl, type = {Master Thesis}, author = {Heberl, Michael}, title = {Power-to-Ammoniak}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-22167}, school = {Ostbayerische Technische Hochschule Regensburg}, pages = {68}, abstract = {Ammoniak ist Grundbaustein f{\"u}r die Herstellung von D{\"u}ngemitteln und dementsprechend f{\"u}r die Nahrungsmittelindustrie unentbehrlich. Ca. 40-50 \% der Weltbev{\"o}lkerung sind von Nahrungsmitteln abh{\"a}ngig, die mit Hilfe von Ammoniakd{\"u}ngern hergestellten wurden. Weltweit wurden alleine im Jahr 2015 181 Mt Ammoniak produziert, wodurch die Ammoniakherstellung mit 1,2 \% am gesamten Energieverbrauch der Welt beteiligt ist und f{\"u}r 0,93 \% der globalen Treibhausgasemissionen zust{\"a}ndig ist. Auch in Zeiten der Energiewende ist diese Grundstoffchemikalie unentbehrlich, ist aber auf einem anderen Wege herzustellen. Ziel dieser Arbeit ist die Darstellung verschiedener M{\"o}glichkeiten zur erneuerbaren Elektrifizierung und Dekarbonisierung der Ammoniakindustrie, wodurch der Einsatz von herk{\"o}mmlichen Energietr{\"a}gern wie Erdgas, Kohle und {\"O}l negiert werden kann. Ammoniak wird aktuell {\"u}ber das Haber-Bosch-Verfahren aus den Rohstoffen Erdgas, Kohle und {\"O}l gewonnen. Bei diesem Verfahren wird {\"u}ber einen Prim{\"a}r- und Sekund{\"a}rreformer Wasserstoff und Stickstoff gewonnen. Andere Gasbestandteile werden gefiltert oder umgewandelt, um sch{\"a}dliche Katalysatorgifte (CO, H2S) zu entfernen. Im Reaktor wird an Eisenkatalysatoren aus Wasserstoff und Stickstoff letztendlich Ammoniak hergestellt. Der Energieverbrauch des Haber-Bosch Verfahrens schwankt zwischen 7,8 MWh/t NH3 f{\"u}r eine moderne und sehr effiziente Anlage mit Erdgas und 13,6 MWh/t NH3 f{\"u}r eine alte mit Kohle betriebene Anlage. An Emissionen treten pro hergestellter Tonne Ammoniak je nach Rohstoff 1,6-3,8 t CO2-eq auf. Neben der Biomassevergasung gibt es mehrere rein elektrische Ans{\"a}tze zur Ammoniakherstellung. Die unterschiedlichen elektrochemischen Ans{\"a}tze zur direkten Ammoniaksynthese, wie der Einsatz von Fl{\"u}ssigsalzelektrolyten oder Feststoffelektrolyten, wurden in Abschnitt 3.2 vorgestellt. Einige dieser Technologien zeigen vielversprechende Ans{\"a}tze, sind jedoch zum aktuellen Zeitpunkt noch zu weit von einem industriellen Einsatz entfernt. Der Einsatz der Wasserelektrolyse in Kombination mit einer Luftzerlegungseinheit ist die derzeit vielversprechendste Methode Ammoniak auf einem strombasierten und dekarbonisierten Wege herzustellen. Bei diesem System wird Wasserstoff im Elektrolyseur und Stickstoff in der Luftzerlegungseinheit hergestellt. Die Ammoniaksynthese findet hierbei in einem Reaktor nach Vorbild des Haber-Bosch-Prozesses statt. Mit diesem System ist ein Energieverbrauch von ca. 10 MWh/t NH3 notwendig. Durch den Einsatz von rein erneuerbar hergestelltem Strom als Energietr{\"a}ger l{\"a}sst sich mit diesem Technologiezusammenschluss die Ammoniakherstellung komplett Emissionsfrei gestalten. Dadurch k{\"o}nnen alleine in Deutschland j{\"a}hrlich bis zu 7,8 Mt CO2-eq eingespart werden. Eine zuk{\"u}nftige Umstrukturierung der Ammoniakherstellung und der gesamten chemischen Industrie ist unabdingbar. Diese kann aber nur parallel mit einem Ausbau erneuerbarer Energien umgesetzt werden. Mit der Wasserelektrolyse und der Luftzerlegungseinheit sind die technischen M{\"o}glichkeiten f{\"u}r diesen Umbau bereits heute gegeben und brauchen nur noch eingesetzt werden.}, language = {de} } @techreport{ThemaKaulSterneretal., author = {Thema, Martin and Kaul, Anja and Sterner, Michael and Heberl, Michael}, title = {Optimierung eines Rieselbett-Bioreaktors f{\"u}r die dynamische mikrobielle Biosynthese von Methan mit Archaeen-Mikroorganismen in Power-to-Gas-Anlagen}, doi = {10.2314/KXP:1815321555}, abstract = {Das {\"u}bergeordnete Ziel des Vorhabens war die Entwicklung neuer technologischer M{\"o}glichkeiten f{\"u}r den biologischen Methanisierungsprozess mit Archaeen1 in Power-to-Gas-Anwendungen. Im Gegensatz zur technisch ausgereiften chemisch-katalytischen Methanisierung sind hier noch Potenziale zur Optimierung verfahrenstechnischer und biologischer Prozesse f{\"u}r das Speicherkonzept Power-to-Gas [7] vorhanden. Dabei sollte zum einen ein Rieselbett-Bioreaktor optimiert, simuliert und f{\"u}r die Hochskalierung vorbereitet werden. Zum anderen sollte eine Kombination optimal geeigneter Mikroorganismen und Packungsmaterialien selektiert und deren Verhalten und Eignung im Reaktor analysiert werden. Das Verhalten des entwickelten Systems sollte zun{\"a}chst im Labor- und Technikumsmaßstab und anschließend im Feldtest an einer bestehenden Power-to-Gas-Anlage untersucht werden. Hauptziel w{\"a}hrend des Feldtests war die Produktion von einspeisef{\"a}higem Methan sowie dessen Einspeisung ins Gasnetz. Ein Hauptziel des Projektes war es, die Normung und Standardisierung notwendiger Systemparameter und Semantik zur Beschreibung und Einbindung biologischer Methanisierungseinheiten in Power-to-Gas-Anlagen voranzutreiben. Dies sollte zum einen die Vergleichbarkeit der wissenschaftlichen Erkenntnisse verbessern und zum anderen unterst{\"u}tzend bei der Kommerzialisierung der Technologie wirken. Aus dem Projekt heraus wurde so die neue Normungsreihe VDI 4635 Power-to-X beim Verein Deutscher Ingenieure angestoßen.}, language = {de} } @inproceedings{KlitsmanBruecklEller, author = {Klitsman, Maksym and Br{\"u}ckl, Oliver and Eller, Johannes}, title = {Analysis and simulation of the population driving behaviour and charging processes at different charging station types with electric vehicles}, series = {NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: 13-14. September 2021, Hamburg}, booktitle = {NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: 13-14. September 2021, Hamburg}, editor = {Schulz, Detlef}, publisher = {VDE-Verlag}, isbn = {978-3-8007-5651-3}, pages = {254 -- 260}, abstract = {Electric vehicles are one of the important components of the energy transition, which is necessary for the CO2 emission reduction. In order to estimate the influence of electromobility on electric grids at present day and in the future, the generation of realistic charge profiles is necessary. The main objective of this study is the development of an algorithm, which generates realistic charge time series of electric vehicles. The very huge and detailed input surveys enable to define different population groups, representing specific driving behaviour. These groups are then composed and scaled up, according to the statistical population structure of a chosen town or city in Germany, and show typical driving behaviour of all inhabitants. The charge profiles are calculated for several charge station types, based on daily electric vehicle user mobility, day type and household type. In addition, charge process occurrence is evaluated through a model, involving charge infrastructure presence, attractiveness of corresponding charge station type and charge process necessity.}, language = {en} } @misc{PershinaSavelievGlavanetal., author = {Pershina, K. V. and Saveliev, Dmitry V. and Glavan, Gašper and Chashin, Dmitri V. and Belyaeva, Inna A. and Fetisov, Leonid Y. and Shamonin (Chamonine), Mikhail}, title = {The voltage response of a structure comprising a magnetoactive-elastomer cylinder and a piezoelectric material to magnetic field step excitations}, series = {The 4th International Baltic Conference on Magnetism (IBCM 2021) : Svetlogorsk, Russia August 29 - September 2, 2021 : Book of Abstracts}, journal = {The 4th International Baltic Conference on Magnetism (IBCM 2021) : Svetlogorsk, Russia August 29 - September 2, 2021 : Book of Abstracts}, publisher = {Immanuel Kant Baltic Federal University, Kaliningrad, Russia}, pages = {182}, language = {en} } @misc{SternerHeberl, author = {Sterner, Michael and Heberl, Michael}, title = {The ORBIT-Project: Biological methanation in a trickle-bed reactor - key results and next steps}, series = {5th Nuremberg Workshop on Methanation and 2nd Generation, N{\"u}rnberg Friedrich-Alexander-Universit{\"a}t, 28.05.2021}, journal = {5th Nuremberg Workshop on Methanation and 2nd Generation, N{\"u}rnberg Friedrich-Alexander-Universit{\"a}t, 28.05.2021}, organization = {Friedrich-Alexander-Universit{\"a}t Erlangen-N{\"u}rnberg / Lehrstuhl f{\"u}r Energieverfahrenstechnik}, language = {en} } @article{RillBauerKirchbeck, author = {Rill, Georg and Bauer, Florian and Kirchbeck, Mathias}, title = {VTT - a virtual test truck for modern simulation tasks}, series = {Vehicle system dynamics}, volume = {59}, journal = {Vehicle system dynamics}, number = {4}, publisher = {Taylor\&Francis}, doi = {10.1080/00423114.2019.1705356}, pages = {635 -- 656}, abstract = {The development of new technologies like advanced driver assistance systems or automated driving requires a flexible simulation environment of sufficient complexity. In general this flexibility is not provided by commercial software packages. This paper presents a three-dimensional and nonlinear hand-made model for heavy commercial vehicles including tractor and trailer as well as tractor and semitrailer combinations that can be used in different simulation environments, as well as in real-time applications. As typical for trucks, the torsional flexibility of the frame and a suspended driver's cabin are taken into account. The design kinematics makes it possible to handle different and quite complex axle suspensions very efficiently. Appropriate force elements are used to model various couplings between tractor and trailer or tractor and semitrailer, respectively. The virtual test truck environment (VTT) coded in ANSI C is extremely portable and can easily be embedded in commercial simulation packages like MATLAB/Simulink. It includes the TMeasy tyre model and offers flexible interfaces to third-party software tools.}, language = {en} } @article{RillBauerTopcagic, author = {Rill, Georg and Bauer, Florian and Topcagic, Edin}, title = {Performance of leaf spring suspended axles in model approaches of different complexities}, series = {Vehicle System Dynamics}, volume = {60}, journal = {Vehicle System Dynamics}, number = {8}, publisher = {Taylor\&Francis}, doi = {10.1080/00423114.2021.1928249}, pages = {2871 -- 2889}, abstract = {Axles with leaf spring suspension systems are still a popular choice in many commercial vehicles. However, leaf springs are not in perfect conformity to standard multibody vehicle models because they combine guidance and suspension in one single element. Combining standard multibody vehicle models with sophisticated finite element leaf spring models results in rather complex and computing time-consuming solutions. Purely kinematic models, defined by lookup tables or the design kinematics approach, cover only some but not all features of the leaf spring suspension. As shown here, the five-link model, which incorporates a quasi-static solution of the leaf spring compliance, provides a very practical model. It is comparatively lean and provides results of sufficient accuracy in the whole application range.}, language = {en} } @misc{Sterner, author = {Sterner, Michael}, title = {Strom - W{\"a}rme - Verkehr - Industrie: das Zusammenspiel der Sektoren {\"u}ber Power-to-X}, series = {Deutscher Ingenieurtag 2021, D{\"u}sseldorf 20. Mai 2021}, journal = {Deutscher Ingenieurtag 2021, D{\"u}sseldorf 20. Mai 2021}, publisher = {VDI-Verlag}, language = {de} } @article{FrazzicaPalombaDawoud, author = {Frazzica, Andrea and Palomba, Valeria and Dawoud, Belal}, title = {Thermodynamic Performance of Adsorption Working Pairs for Low-Temperature Waste Heat Upgrading in Industrial Applications}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {8}, publisher = {MDPI}, doi = {10.3390/app11083389}, abstract = {The present work aims at the thermodynamic analysis of different working pairs in adsorption heat transformers (AdHT) for low-temperature waste heat upgrade in industrial processes. Two different AdHT configurations have been simulated, namely with and without heat recovery between the adsorbent beds. Ten working pairs, employing different adsorbent materials and four different refrigerants, have been compared at varying working boundary conditions. The effects of heat recovery and the presence of a temperature gradient for heat transfer between sinks/sources and the AdHT components have been analyzed. The achieved results demonstrate the possibility of increasing the overall performance when internal heat recovery is implemented. They also highlight the relevant role played by the existing temperature gradient between heat transfer fluids and components, that strongly affect the real operating cycle of the AdHT and thus its expected performance. Both extremely low, i.e., 40-50 degrees C, and low (i.e., 80 degrees C) waste heat source temperatures were investigated at variable ambient temperatures, evaluating the achievable COP and specific energy. The main results demonstrate that optimal performance can be achieved when 40-50 K of temperature difference between waste heat source and ambient temperature are guaranteed. Furthermore, composite sorbents demonstrated to be the most promising adsorbent materials for this application, given their high sorption capacity compared to pure adsorbents, which is reflected in much higher achievable specific energy.}, language = {en} } @article{ThemaWeidlichKauletal., author = {Thema, Martin and Weidlich, Tobias and Kaul, Anja and B{\"o}llmann, Andrea and Huber, Harald and Bellack, Annett and Karl, J{\"u}rgen and Sterner, Michael}, title = {Optimized biological CO2-methanation with a pure culture of thermophilic methanogenic archaea in a trickle-bed reactor}, series = {Bioresource Technology}, journal = {Bioresource Technology}, number = {333}, publisher = {Elsevier}, doi = {10.1016/j.biortech.2021.125135}, abstract = {In this study, a fully automated process converting hydrogen and carbon dioxide to methane in a high temperature trickle-bed reactor was developed from lab scale to field test level. The reactor design and system performance was optimized to yield high methane content in the product gas for direct feed-in to the gas grid. The reaction was catalyzed by a pure culture of Methanothermobacter thermoautotrophicus IM5, which formed a biofilm on ceramic packing elements. During 600 h in continuous and semi-continuous operation in countercurrent flow, the 0.05 m3 reactor produced up to 95.3 \% of methane at a methane production rate of 0.35 mCH43mR-3h-1. Adding nitrogen as carrier gas during startup, foam control and dosing of ammonium and sodium sulfide as nitrogen and sulfur source were important factors for process automation.}, language = {en} } @article{GaertnerRankHeberletal., author = {G{\"a}rtner, Sebastian and Rank, Daniel and Heberl, Michael and Gaderer, Matthias and Dawoud, Belal and Haumer, Anton and Sterner, Michael}, title = {Simulation and Techno-Economic Analysis of a Power-to-Hydrogen Process for Oxyfuel Glass Melting}, series = {Energies}, volume = {14}, journal = {Energies}, number = {24}, publisher = {MDPI}, doi = {10.3390/en14248603}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-22713}, abstract = {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.}, language = {en} } @article{SchorrZentnerZimmermannetal., author = {Schorr, Philipp and Zentner, Lena and Zimmermann, Klaus and B{\"o}hm, Valter}, title = {Jumping locomotion system based on a multistable tensegrity structure}, series = {Mechanical systems and signal processing}, journal = {Mechanical systems and signal processing}, number = {152}, publisher = {Elsevier}, doi = {10.1016/j.ymssp.2020.107384}, abstract = {All known locomotion principles are limited respective to environmental conditions. Often, the occurrence of obstacles or gaps means the break-off for the operating motion systems. For such circumstances, a controllable jumping locomotion is required to cross these barriers. However, this locomotion demands sophisticated requirements to the actuation. The abrupt actuation is commonly realized by high dynamic actuators or complex mechanisms. In this work, a simple solution utilizing the multistability of a compliant tensegrity structure is described. Therefore, a two-dimensional tensegrity structure featuring four stable equilibria is considered. Based on bifurcation analyses a feasible actuation to control the current equilibrium configuration is derived. Changing between selected equilibrium states enables a great difference in potential energy, which yields a jumping motion of the structure. Based on numerical simulations a suitable actuation strategy is chosen to overcome obstacle and steps by jumping forward or backward, respectively. The theoretical approach is examined experimentally with a prototype of the multistable tensegrity structure. (c) 2020 Elsevier Ltd. All rights reserved. All known locomotion principles are limited respective to environmental conditions. Often, the occurrence of obstacles or gaps means the break-off for the operating motion systems. For such circumstances, a controllable jumping locomotion is required to cross these barriers. However, this locomotion demands sophisticated requirements to the actuation. The abrupt actuation is commonly realized by high dynamic actuators or complex mechanisms. In this work, a simple solution utilizing the multistability of a compliant tensegrity structure is described. Therefore, a two-dimensional tensegrity structure featuring four stable equilibria is considered. Based on bifurcation analyses a feasible actuation to control the current equilibrium configuration is derived. Changing between selected equilibrium states enables a great difference in potential energy, which yields a jumping motion of the structure. Based on numerical simulations a suitable actuation strategy is chosen to overcome obstacle and steps by jumping forward or backward, respectively. The theoretical approach is examined experimentally with a prototype of the multistable tensegrity structure.}, language = {en} } @article{HaugVetter, author = {Haug, Sonja and Vetter, Miriam}, title = {Altersgerechtes Wohnen im Quartier}, series = {Standort - Zeitschrift f{\"u}r angewandte Geographie}, volume = {45}, journal = {Standort - Zeitschrift f{\"u}r angewandte Geographie}, publisher = {Springer Nature}, issn = {1432-220X}, doi = {10.1007/s00548-020-00678-3}, pages = {11 -- 17}, abstract = {Im Alter nimmt das Quartier aufgrund geringerer Aktionsradien an Bedeutung zu. Der Beitrag befasst sich mit der Frage, welche Besonderheiten sich bei Senioren-Haushalten im Hinblick auf Wohnen und soziale Teilhabe zeigen. Aus dem Projekt MAGGIE werden Ergebnisse einer schriftlichen Haushaltsbefragung (N=195) in der Wohngenossenschaft Margaretenau Regensburg dargestellt. Hierbei wird auf die aktuelle und zuk{\"u}nftige Wohnsituation, den Ver{\"a}nderungsbedarf, den Wunsch nach Gemeinschaftsangeboten und die soziale Einbettung eingegangen. Es zeigt sich eine geringe Ver{\"a}nderungsbereitschaft und ein {\"u}berdurchschnittlich hohes Maß an lokalem Sozialkapital. Am Ende werden Schlussfolgerungen f{\"u}r das Sanierungs- und Quartiersmanagement gezogen.}, subject = {Alter}, language = {de} } @article{PalombaNowakDawoudetal., author = {Palomba, Valeria and Nowak, Sebastian and Dawoud, Belal and Frazzica, Andrea}, title = {Dynamic modelling of Adsorption systems: a comprehensive calibrated dataset for heat pump and storage applications}, series = {Journal of energy storage}, volume = {33}, journal = {Journal of energy storage}, publisher = {Elsevier}, doi = {10.1016/j.est.2020.102148}, abstract = {The growing efforts for the development of clean and efficient energy systems require the use of a multi-disciplinary approach and the integration of multiple generation appliances. Among the fields that can be considered enabling technologies, adsorption systems for air conditioning and thermal energy storages, are constantly increasing their maturity. However, for a proper design and integration of such systems, there is the need for a simulation framework that is reliable and computationally convenient. In the present paper, the implementation of a dynamic model for adsorption systems is presented, which includes different components (adsorber, phase changer, sorption materials) and is structured as a library. Modelica language and the commercial software Dymola (R) are used for the analysis. Data for different heat exchangers and working pairs are calibrated using experimental results and the calibrated model is subsequently used for the design of an adsorber based on a plate heat exchanger for thermal energy storage applications. The results proved that the model is fast and can reproduce experimental results with good accuracy, thus being a useful tool for the design and optimization of the different components of sorption systems.}, language = {en} } @article{SovacoolCabezaPiselloetal., author = {Sovacool, Benjamin K. and Cabeza, Luisa F. and Pisello, Anna Laura and Colladon, Andrea Fronzetti and Larijani, Hatef Madani and Dawoud, Belal and Martiskainen, Mari}, title = {Decarbonizing household heating: Reviewing demographics, geography and low-carbon practices and preferences in five European countries}, series = {Renewable \& Sustainable Energy Reviews}, journal = {Renewable \& Sustainable Energy Reviews}, number = {139}, publisher = {Elsevier}, doi = {10.1016/j.rser.2020.110703}, pages = {1 -- 28}, abstract = {What commonalities are there in sustainable or unsustainable heating practices in five high-income, high-emitting western European countries? What preferences do a nationally representative sample of the public in these countries hold towards low-carbon options? It is imperative that climate policy researchers and practitioners grapple with the difficulty of decarbonizing heat, which remains the largest single end-use service worldwide and which accounts about half of total final energy consumption. Based on a comparative assessment of five representative national surveys in Germany (N = 2009), Italy (N = 2039), Spain (N = 2038), Sweden (N = 2023), and the United Kingdom (N = 2000), this study explores the demographics and geography of household heat decarbonisation in Europe. By analyzing our country level data as well as our combined sample of 10,109 respondents, it investigates how people conceive of the purposes of low-carbon heat, their preferences for particular forms of heat supply, and their (at times odd) practices of heat consumption and temperature settings. Grounded in its original data, the study organizes its findings inductively across the five themes of literacy (heating knowledge, awareness and control), sustainability (heating practices, dynamics and conflicts), temperature (heating satisfaction and preferences), desirability of change (low-carbon heating priorities, business models and trust), and culture (country and national variation). The study also explores intersections between these dimensions, using multivariate analysis, as well as how preferences differ according to varying types of actors as well as geography and space.}, language = {en} } @article{MonkmanSindersbergerPremetal., author = {Monkman, Gareth J. and Sindersberger, Dirk and Prem, Nina and Diermeier, Andreas and Szecsey, Tamara}, title = {Dielectric behaviour of magnetic hybrid materials}, series = {Physical Sciences Reviews}, volume = {7}, journal = {Physical Sciences Reviews}, number = {10}, publisher = {de Gruyter}, doi = {10.1515/psr-2019-0121}, pages = {1169 -- 1185}, abstract = {The objectives of this work include the analysis of electrical and magnetic properties of magneto-elastic hybrid materials with the intention of developing new techniques for sensor and actuator applications. This includes the investigation of dielectric properties at both low and high frequencies. The behaviour of capacitors whose dielectrics comprise magnetic hybrid materials is well known. Such interfacial magnetocapacitance can be varied according to magnetic content, magnetic flux density and the relative permittivity of the polymer matrix together with other dielectric content. The basic function of trapping electrical charges in polymers (electrets) is also established technology. However, the combination of magnetoactive polymers and electrets has led to the first electromagnetic device capable of adhering to almost any material, whether magnetically susceptible or not. During the course of this research, in addition to dielectrics, electrically conductive polymers based on (PDMS) matrices were developed in order to vary the electrical properties of the material in a targeted manner. In order to ensure repeatable results, this demanded new fabrication techniques hitherto unavailable. The 3D printing of silicones is far from being a mature technology and much pioneering work was necessary before extending the usual 3 d.o.f. to include orientation about and diffusion of particles in these three axes, thus leading to the concept of 6D printing. In 6D printing, the application of a magnetic field can be used during the curing process to control the particulate distribution and thus the spatial filler particle density as desired. Most of the devices (sensors and actuators) produced by such methods contain levels of carbonyl iron powder (CIP) embedded magnetic filler of up to 70 wt\%. Contrary to this, a hitherto neglected research area, namely magnetoactive polymers (MAPs) having significantly lower magnetic particle concentrations (1 to 3 wt\% CIP) were also investigated. With filler concentrations lower than 3 wt\%, structures are formed which are completely absent at higher filler levels. CIP concentrations in the range of 1wt\% demonstrate the formation of toroidal structures. Further development of coherent rings with a compact order results as filler concentrations increase towards 2 wt\%. Above 3 wt\% the structure eventually disintegrates to the usual random order found in traditional MAP with higher CIP content. Structured samples containing 1\%-3 wt\% CIP were investigated with the aid of X-ray tomography where solitary ring structures can be observed and eventually the formation of capillary doubles. Over wavelengths ranging from 1 to 25 µm, spectroscopic analysis of thin film MAP samples containing 2 wt\% CIP revealed measurable magnetic-field-dependent changes in IR absorption at a wavenumber 2350 (λ = 4.255 µm). This was found to be due to the diamagnetic susceptibility of atmospheric carbon dioxide (CO2). Consequently, the first potential application for sparse matrix MAPs was found.}, language = {en} } @article{SchwanzerSchillingerMieslingeretal., author = {Schwanzer, Peter and Schillinger, Maximilian and Mieslinger, Johann and Walter, Stefanie and Hagen, Gunter and Maerkl, Susanne and Haft, Gerhard and Dietrich, Markus and Moos, Ralf and Gaderer, Matthias and Rabl, Hans-Peter}, title = {A Synthetic Ash-Loading Method for Gasoline Particulate Filters with Active Oil Injection}, series = {SAR International Journal of Engines}, volume = {14}, journal = {SAR International Journal of Engines}, number = {4}, publisher = {SAE International}, issn = {1946-3936}, doi = {10.4271/03-14-04-0029}, pages = {493 -- 506}, abstract = {To reduce particulate emissions, the use of particulate filters in diesel engines is meanwhile state of the art, while the integration of such systems in gasoline engines is now also necessary in order to comply with today's regulations. Over its lifetime, a gasoline particulate filter (GPF) collects ash components of fuel, lubrication oil, and materials originating from the catalytic coating and from engine abrasion. In the development and application process, synthetic ashing from GPFs is challenging. The ash of the lubrication oil can be increased in various ways, like oil-doped fuel, a separate oil burner, or changes in the piston-cylinder system of the engine. However, these methods show major disadvantages. For this reason, an improved approach is presented in this study, which allows a quick response to changes in combustion (e.g., engine knocking) and producing ash, which is more realistic due to its primary particle size and the density of ash plugs, in a shorter time. Therefore, an approach to accelerate ash loading by active oil injection using a multi-point injection (MPI) system is introduced. With the help of this methodology, an ashing capacity of 1.21 g/h is implemented, which is a high rate compared to other investigations. The primary particle size (evaluated by means of a transmission electron microscope), is in the same size range as those detected at the full-load curve during regular operation. A computer tomographic (CT) analysis of the incinerated particulate filter also shows that a very high density of ash plugs can be realized, which has also been found in the literature for real applications. In addition, with the help of a mass spectrometer (MS) and an intermediate weighing of the particulate filter, the current ash loading of the GPF could be determined with an accuracy of 1\%.}, language = {en} } @article{SchmidtStraubSindersbergeretal., author = {Schmidt, Henrik and Straub, Benedikt B. and Sindersberger, Dirk and Br{\"o}ckel, Ulrich and Monkman, Gareth J. and Auernhammer, G{\"u}nter}, title = {Collision and separation of nickel particles embedded in a Poly dimethylsiloxan matrix under a rotating magnetic field: A strong magneto active function}, series = {Colloid and Polymer Science}, volume = {299}, journal = {Colloid and Polymer Science}, publisher = {Springer}, doi = {10.1007/s00396-020-04784-4}, pages = {955 -- 967}, abstract = {In order to function as soft actuators, depending on their field of use, magnetorheological elastomers (MREs) must fulfill certain criteria. To name just a few, these can include rapid response to external magnetic fields, mechanical durability, mechanical strength, and/or large deformation. Of particular interest are MREs which produce macroscopic deformation for small external magnetic field variations. This work demonstrates how this can be achieved by just a small change in magnetic field orientation. To achieve this, (super)paramagnetic nickel particles of size ≈ 160 μm were embedded in a non-magnetic polydimethylsiloxan (PDMS) (661-1301 Pa) and their displacement in a stepwise rotated magnetic field (170 mT) recorded using a video microscope. Changes in particle aggregation resulting from very small variations in magnetic field orientation led to the observation of a new strongly magneto-active effect. This configuration is characterized by an interparticle distance in relation to the angle difference between magnetic field and particle axis. This causes a strong matrix deformation which in turn demonstrates hysteresis on relaxation. It is shown that the occurrence strongly depends on the particle size, particle distance, and stiffness of the matrix. Choosing the correct parameter combination, the state can be suppressed and the particle-matrix system demonstrates no displacement or hysteresis. In addition, evidences of non-negligible higher order magnetization effects are experimentally ascertained which is qualitatively in agreement with similar, already theoretically described, particle systems. Even at larger particle geometries, the new strongly magneto-active configuration is preserved and could create macroscopic deformation changes.}, language = {en} } @inproceedings{RiegerOetjenvandeParetal., author = {Rieger, Anna and Oetjen, Arne and van de Par, Steven and Rabl, Hans-Peter}, title = {Geh{\"o}rbezogene Modellierung der Dissonanz}, series = {Tagungsband DAGA 2021: 47. Jahrestagung f{\"u}r Akustik, 15.-18. August 2021, Wien und Online}, volume = {47}, booktitle = {Tagungsband DAGA 2021: 47. Jahrestagung f{\"u}r Akustik, 15.-18. August 2021, Wien und Online}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik e.V.}, pages = {1034 -- 1037}, language = {de} } @incollection{BauerGawlikSterneretal., author = {Bauer, Franz and Gawlik, Julia and Sterner, Michael and Hamacher, Thomas}, title = {{\"U}bergreifende Energiesystemmodellierung}, series = {Optionen f{\"u}r ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen - Potentiale. 3. Roadmap des Kopernikus-Projektes P2X, Phase II}, booktitle = {Optionen f{\"u}r ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen - Potentiale. 3. Roadmap des Kopernikus-Projektes P2X, Phase II}, editor = {Ausfelder, Florian and Dura, Hanna}, publisher = {DECHEMA Gesellschaft f{\"u}r Chemische Technik und Biotechnologie e.V.}, address = {Frankfurt a.M.}, isbn = {978-3-89746-236-6}, pages = {19 -- 33}, language = {de} } @article{LindnerPipaKarpenetal., author = {Lindner, Matthias and Pipa, Andrei V. and Karpen, Norbert and Hink, Ruediger and Berndt, Dominik and Foest, R{\"u}diger and Bonaccurso, Elmar and Weichwald, Robert and Friedberger, Alois and Caspari, Ralf and Brandenburg, Ronny and Schreiner, Rupert}, title = {Icing Mitigation by MEMS-Fabricated Surface Dielectric Barrier Discharge}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {23}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/app112311106}, pages = {1 -- 17}, abstract = {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.}, language = {en} } @misc{SchwanzerDietrichGadereretal., author = {Schwanzer, Peter and Dietrich, Markus and Gaderer, Matthias and Rabl, Hans-Peter}, title = {Detektion unterschiedlicher Medien in Gasoline Particulate Filter (GPF) mit Hilfe eines Radio-Frequenz (RF-) Sensors}, series = {Bayerische Wissenschaftsforum - BayWISS 2020}, journal = {Bayerische Wissenschaftsforum - BayWISS 2020}, language = {de} } @book{AltmannGebhardEmbergeretal., author = {Altmann, Robert and Gebhard, J{\"u}rgen and Emberger, Peter and Thuneke, Klaus and Rabl, Hans-Peter and Remmele, Edgar}, title = {Z{\"u}nd- und Brennverhalten von Pflanzen{\"o}lkraftstoff und {\"U}bertragung auf einen Motor der Abgasstufe V}, volume = {69}, publisher = {Technologie- und F{\"o}rderzentrum im Kompetenzzentrum f{\"u}r Nachwachsende Rohstoffe}, address = {Straubing}, issn = {1614-1008}, pages = {188}, abstract = {Durch den Ersatz von Dieselkraftstoff durch Raps{\"o}lkraftstoff (R100) k{\"o}nnen Treibhausgasemissionen reduziert werden. F{\"u}r einen st{\"o}rungsfreien Betrieb eines Motors mit Raps{\"o}lkraftstoff sind jedoch Modifikationen an Motorkomponenten und Motorsteuerger{\"a}t notwendig, um eine effiziente Verbrennung im Motor zu erreichen. Ziel des Vorhabens ist die Erarbeitung von Grundlagen zur Auslegung der Motorsteuerung pflanzen{\"o}ltauglicher Offroad-Motoren mit moderner Abgasnachbehandlung mit anschließender entsprechender Abstimmung der Motorapplikation am Pr{\"u}fstand. Grundlegende Untersuchungen der physikalischen Prozessabl{\"a}ufe von R100 bei der Einspritzung werden an einem hydraulischen Druckanstiegsanalysator (HDA) und einer Hochdruck-Hochtemperatur-Kammer (HDHT-Kammer) durchgef{\"u}hrt. Unterschiede im Z{\"u}nd- und Brennverhalten werden in einer Konstantvolumenbrennkammer untersucht. Abschließend werden die Erkenntnisse am Motorenpr{\"u}fstand auf einen DEUTZ-Motor {\"u}bertragen, dessen Einspritzsystem auch bei den grundlegenden Untersuchungen verwendet wurde. Die Ergebnisse zeigen, dass das Einspritzverhalten von R100 eine h{\"o}here Sensitivit{\"a}t gegen{\"u}ber Kraftstofftemperaturvariationen aufweist als Dieselkraftstoff. Bei niedrigen raftstofftemperaturen sind mit R100 ein l{\"a}ngerer {\"O}ffnungsverzug und eine geringere Einspritzmenge festzustellen. Um diesen Einfluss bei der Einspritzstrategie zu kompensieren, ist die Kenntnis der Kraftstofftemperatur im Injektor notwendig. Eine weitere Herausforderung stellt die Gemischaufbereitung dar, hier f{\"u}hren unter anderem die h{\"o}here Viskosit{\"a}t und h{\"o}here Siedetemperaturen von R100 zu einem schm{\"a}leren Spritzwinkel und verz{\"o}gerter Verdampfung im Vergleich zum Dieselkraftstoff. Eine Erh{\"o}hung des Einspritzdrucks und h{\"o}here Temperaturen und Dr{\"u}cke in der Brennkammer verbessern die Gemischaufbereitung. Bei Bedingungen von mittlerer und hoher Last ist der Z{\"u}ndverzug von R100 k{\"u}rzer und das Verbrennungsverhalten {\"a}hnlich zum Dieselkraftstoff. Eine geringere W{\"a}rmefreisetzung von R100 wird durch den geringeren Heizwert verursacht. Unter Bedingungen von niedriger Last und Motorstart ist ein l{\"a}ngerer Z{\"u}ndverzug von R100 im Vergleich zum Dieselkraftstoff festzustellen. Eine Steigerung des Einspritzdrucks und h{\"o}here Brennkammerdr{\"u}cke und -temperaturen f{\"u}hren bei beiden Kraftstoffen zu k{\"u}rzeren Z{\"u}ndverz{\"u}gen, der Einfluss dieser Parameter ist jedoch f{\"u}r R100 st{\"a}rker als f{\"u}r Dieselkraftstoff. Voreinspritzungen f{\"u}hren bei beiden Kraftstoffen zu einer Verk{\"u}rzung des Z{\"u}ndverzugs der Haupteinspritzung und zu einer geringeren W{\"a}rmefreisetzungsrate. Am Motorpr{\"u}fstand ist bei gleicher Motorapplikation mit R100 eine geringere Leistung als mit Dieselkraftstoff festzustellen. Nach Angleichung der Motorleistung durch Anhebung der Einspritzmenge von R100 sind im Rohabgas Stickstoffoxid (NOX)- und Kohlenstoffmonoxidemissionen auf gleichem Niveau zu Dieselkraftstoff zu beobachten sowie geringere Partikelemissionen. Unter Verwendung eines DoE Vorgehens kann der Partikel-NOX - trade-off von R100 optimiert und Einstellparameter gefunden werden, in denen sowohl niedrigere NOX als auch niedrigere Partikelemissionen im Vergleich zum Dieselkraftstoff resultieren. Das installierte Abgasnachbehandlungssystem, bestehend aus einem Dieseloxidationskatalysator (DOC), Dieselpartikelfilter (DPF) und selektivem katalytischem Reduktionssystem (SCR), arbeitet f{\"u}r beide Kraftstoffe {\"a}hnlich und es scheint keine Anpassung der Dosierungsstrategie der w{\"a}ssrigen Harnstoffl{\"o}sung notwendig zu sein. Eine Regeneration des Partikelfilters mit R100 war nach Optimierung der Einstellparameter der Drosselklappe m{\"o}glich. Motorkaltstart und Leerlauf sind herausfordernde Betriebsphasen, die f{\"u}r R100 einer weiteren Optimierung bed{\"u}rfen. Eine Temperierung von R100 im Injektor auf 50-60 °C sowie eine Kompensation der Einspritzmenge in Abh{\"a}ngigkeit von der Kraftstofftemperatur sind m{\"o}gliche Verbesserungsmaßnahmen. Zudem kann durch einen fr{\"u}heren Einspritzbeginn von R100 das Verbrennungsverhalten angepasst werden. Die Motorpr{\"u}fstandsuntersuchungen best{\"a}tigen qualitativ die Erkenntnisse die mit dem hydraulischen Druckanstiegsanalysator (HDA), der Hochdruck-Hochtemperatur-Kammer (HDHT-Kammer) und der Konstantvolumenbrennkammer gewonnen wurden. Weitere Untersuchungen sind notwendig, um die Ergebnisse auf einen baugleichen, in einer mobilen Arbeitsmaschine eingebauten Motor zu transferieren, damit Informationen zur Dauerhaltbarkeit unter realen Bedingungen erhalten werden k{\"o}nnen. Weiterf{\"u}hrende Forschungsarbeiten sind im Bereich der Betriebsphasen des Motorkaltstarts und Leerlaufs mit Raps{\"o}lkraftstoff n{\"o}tig, um einen dauerhaft st{\"o}rungsfreien Betrieb in diesen Betriebsphasen zu erreichen. Die erzielten Erkenntnisse deuten darauf hin, dass hier noch viel Verbesserungspotenzial vorhanden ist.}, subject = {Biokraftstoff}, language = {de} } @misc{OetjenRiegerRabletal., author = {Oetjen, Arne and Rieger, Anna and Rabl, Hans-Peter and van de Par, Steven}, title = {The role of dissonance in the sound quality perception for electric vehicles}, series = {The Journal of the Acoustical Society of America}, volume = {148}, journal = {The Journal of the Acoustical Society of America}, number = {4}, publisher = {Acoustical Society of America}, doi = {10.1121/1.5147356}, abstract = {Tonal components can be regarded as one of the most relevant components for interior sound quality of electric vehicles, especially at low speeds. Sources for these tones are for example the vehicles' drivetrains but also other technical components. Depending on the driving conditions, due to the interaction of various dominant sources, audible tone complexes can occur. Similar to musical intervals, the different frequency ratios within these complexes can result in consonant or dissonant sensations. The strength of this sensation does not only depend on the frequency relation of the tones but also on their relative levels. In this study, different musical intervals were subjectively rated in terms of their specific consonant or dissonant character. Using an adaptive procedure, sound pairs, each consisting of a two-tone signal, where adjusted to equal dissonance by varying the level of the second tone of one of the two-tone signals. Using the same paradigm, also pairs of equal vehicle sound quality were obtained. With these results, it is possible to quantify dissonance, and theinfluence of dissonance on sound quality expressed in terms of level differences of two-tone signals. These results can help to make the concept of dissonance more useful for sound-engineering applications.}, language = {en} } @incollection{WalterSchwanzerHagenetal., author = {Walter, Stefanie and Schwanzer, Peter and Hagen, Gunter and Haft, Gerhard and Dietrich, Markus and Rabl, Hans-Peter and Moos, Ralf}, title = {Hochfrequenzsensorik zur direkten Beladungserkennung von Benzinpartikelfiltern}, series = {Automobil-Sensorik 3}, booktitle = {Automobil-Sensorik 3}, editor = {Tille, Thomas}, publisher = {Springer Vieweg}, address = {Berlin}, isbn = {978-3-662-61259-0}, doi = {10.1007/978-3-662-61260-6_7}, pages = {185 -- 208}, abstract = {In Folge der Versch{\"a}rfung der gesetzlichen Abgasnormen wurden f{\"u}r direkt-einspritzende Benzinmotoren Partikelfilter notwendig. Zur Beladungs{\"u}berwachung k{\"o}nnen aufgrund stark unterschiedlicher Rahmenbedingungen die aus Dieselmotoren bekannten Systeme, wie dem Differenzdrucksensor, nur eingeschr{\"a}nkt {\"u}bernommen werden. Ein hochfrequenzbasiertes Verfahren koppelt mittels Antennen elektromagnetische Wellen in das Filtergeh{\"a}use ein, deren Ausbreitungsverhalten durch die dielektrischen Eigenschaften des eingelagerten Rußes beeinflusst wird. Hierdurch kann bei Auswertung von Transmissionsd{\"a}mpfung oder Resonanzfrequenzen die Rußbeladung direkt detektiert werden.}, language = {en} } @misc{SchwanzerMieslingerRabletal., author = {Schwanzer, Peter and Mieslinger, Johann and Rabl, Hans-Peter and Dietrich, Markus and Haft, Gerhard and Walter, Stefanie and Hagen, Gunter and Moos, Ralf and Gaderer, Matthias}, title = {Monitoring of a Particulate Filter for Gasoline Direct Injection Engines with a Radio-Frequency-Sensor}, series = {11th International Exhaust Gas and Particulate Emissions Forum, 3.-4.3.2020, Ludwigsburg, Germany}, journal = {11th International Exhaust Gas and Particulate Emissions Forum, 3.-4.3.2020, Ludwigsburg, Germany}, abstract = {In order to comply with future emission regulations, the use of particulate filters in vehicles with direct injection gasoline engines is essential. The current amount of soot and ash in the filter is calculated by a soot load model in the electronic control unit in combination with a differential pressure sensor determining the pressure drop over the particulate filter. Active regeneration is initiated if the calculated amount of soot or the measured differential pressure is too high. This is associated with additional fuel consumption. An on-board diagnosis for the particulate filter is currently not part of the Euro 6d emission standard. For future exhaust emission standards, on-board diagnosis or active monitoring of the particulate filter is conceivable. One of the benefits of monitoring is the fact that unnecessary active regenerations can be avoided. As a result, there is no additional fuel consumption due to misinterpretations of the amount of soot in the filter. For active monitoring of the particulate filter, a radiofrequency (RF-) sensor, that detects the soot loading of the filter with electromagnetic waves directly, can be used. Such a system has the advantage that by utilizing the filter as a sensor more precise information about the current state of the filter, e.g. a possible damage, can be provided. Worst-case considerations of filter damages, tested at an engine test bench show the advantages which are entailed by a system like that. By means of partial regeneration of the particulate filter it is demonstrated how the remaining amount of soot in the filter can be detected in a better way in comparison to the differential pressure sensor by using the RF-sensor.}, language = {en} } @article{Briem, author = {Briem, Ulrich}, title = {Die neue VDI 2500 : Faserseilwissen kompakt}, series = {Logistik f{\"u}r Unternehmen}, journal = {Logistik f{\"u}r Unternehmen}, number = {11-12}, pages = {36 -- 37}, abstract = {Die Richtlinie VDI 2500 „Faserseile" hat 1990 erstmals zusammenfassend den Stand der Technik auf dem Gebiet der Faserseile dargestellt und wertvolle Infor-mationen {\"u}ber Aufbau, Auswahl, Konfek-tionierung und {\"U}berwachung von Faser-seilen gegeben. Die jetzt erscheinende zweite Auflage enth{\"a}lt eine Vielzahl wichtiger technischer Neuerungen f{\"u}r die Praxis. Zu nennen sind hier die hochfesten Fasern und deren Beschichtung sowie die erstmals systematisch aufgef{\"u}hrten Sei-lendverbindungen und ein Ausblick auf die zuk{\"u}nftig bedeutsamen sogenannten Hybridseile. Eine Checkliste hilft bei der richtigen Auswahl und Bemessung von Faserseilen. Bei den Normen wurde - soweit m{\"o}glich - auf europ{\"a}ische Normen verwiesen.}, language = {de} } @article{Briem, author = {Briem, Ulrich}, title = {Umlaufbiegewechselzahl von verdichteten Seildr{\"a}hten}, series = {Draht}, journal = {Draht}, number = {6}, pages = {14 -- 15}, language = {de} } @misc{SchrollDecker, author = {Schroll-Decker, Irmgard}, title = {Rezension zu: Ethik des Wissens. Freiheit und Verantwortung der Wissenschaft in Zeiten des Klimawandels. oekom Verlag (M{\"u}nchen) 2019. ISBN 978-3-96238-163-9}, series = {socialnet Rezensionen}, journal = {socialnet Rezensionen}, issn = {2190-9245}, language = {de} } @article{RomeisKostrovKramarenkoetal., author = {Romeis, Dirk and Kostrov, Sergei A. and Kramarenko, Elena Yu and Stepanov, Gennady V. and Shamonin (Chamonine), Mikhail and Saphiannikova, M.}, title = {Magnetic-field-induced stress in confined magnetoactive elastomers}, series = {Soft Matter}, volume = {16}, journal = {Soft Matter}, number = {39}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, doi = {10.1039/D0SM01337D}, pages = {9047 -- 9058}, abstract = {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.}, language = {en} } @article{GeilfussDawoud, author = {Geilfuß, Kristina and Dawoud, Belal}, title = {Analytical investigation of a zeolite-NaY-water adsorption heat and cold storage and its integration into a steam power process}, series = {Energy}, volume = {195}, journal = {Energy}, number = {March}, publisher = {Elsevier}, doi = {10.1016/j.energy.2020.116977}, abstract = {tabilizing the effects of greenhouse gas emissions on the atmosphere is a key step towards solving the global climate change problems. Storage technologies play an essential role in compensating the discrepancy between surplus energy and peak times. Sorption processes, in particular, offer an environment friendly way for almost loss-free heat (of adsorption or absorption) and cold storage. This work is dedicated first to analytically investigate the potential of applying NaY-Water/Zeolite as a working pair for heat and cold storage upon utilizing high temperature heat. It turned out that, the mass of the adsorber heat exchanger increases the useful specific heat stored from 229 kWh/tzeolite for the ideal storage to 538 kWh/tzeolite or even higher depending on the thermal capacity of the adsorber heat exchanger (AdsHX). Contrary to that trend, COP will decrease with increasing the thermal capacity of the AdsHX. Sensible heat losses between charging and discharging phases do have a negative effect on both stored heating capacity and COP. In addition, an innovative hybrid steam power cum adsorption storage process is introduced and analytically investigated at different ambient conditions and time scenarios for on-peak and off-peak durations over the day. The introduced hybrid process seems quite promising in achieving electrical power production and efficiency enhancements during peak load durations. The extent of enhancing both performance indicators increases with increasing the ambient temperature difference between peak and off-peak times.}, language = {en} } @article{SnarskiiShamoninChamonineYuskevich, author = {Snarskii, Andrei A. and Shamonin (Chamonine), Mikhail and Yuskevich, Pavel}, title = {Effective medium theory for the elastic properties of composite materials with various percolation thresholds}, series = {Materials}, volume = {13}, journal = {Materials}, number = {5}, publisher = {MPDI}, address = {Basel}, doi = {10.3390/ma13051243}, pages = {1 -- 19}, abstract = {It is discussed that the classical effective medium theory for the elastic properties of random heterogeneous materials is not congruous with the effective medium theory for the electrical conductivity. In particular, when describing the elastic and electro-conductive properties of a strongly inhomogeneous two-phase composite material, the steep rise of effective parameters occurs at different concentrations. To achieve the logical concordance between the cross-property relations, a modification of the effective medium theory of the elastic properties is introduced. It is shown that the qualitative conclusions of the theory do not change, while a possibility of describing a broader class of composite materials with various percolation thresholds arises. It is determined under what conditions there is an elasticity theory analogue of the Dykhne formula for the effective conductivity. The theoretical results are supported by known experiments and show improvement over the existing approach. The introduction of the theory with the variable percolation threshold paves the way for describing the magnetorheological properties of magnetoactive elastomers. A similar approach has been recently used for the description of magneto-dielectric and magnetic properties.}, language = {en} } @article{SnarskiiShamoninChamonineYuskevichetal., author = {Snarskii, Andrei A. and Shamonin (Chamonine), Mikhail and Yuskevich, Pavel and Saveliev, Dmitry V. and Belyaeva, Inna A.}, title = {Induced anisotropy in composite materials with reconfigurable microstructure: Effective medium model with movable percolation threshold}, series = {Physica A: Statistical Mechanics and its Applications}, volume = {560}, journal = {Physica A: Statistical Mechanics and its Applications}, number = {December}, publisher = {Elsevier}, doi = {10.1016/j.physa.2020.125170}, abstract = {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.}, language = {en} } @article{SavelievBelyaevaChashinetal., author = {Saveliev, Dmitry V. and Belyaeva, Inna A. and Chashin, Dmitri V. and Fetisov, Leonid Y. and Romeis, Dirk and Kettl, Wolfgang and Kramarenko, Elena Yu and Saphiannikova, M. and Stepanov, Gennady V. and Shamonin (Chamonine), Mikhail}, title = {Giant extensional strain of magnetoactive elastomeric cylinders in uniform magnetic fields}, series = {Materials}, volume = {13}, journal = {Materials}, number = {15}, publisher = {MDPI}, address = {Basel}, issn = {1996-1944}, doi = {10.3390/ma13153297}, pages = {1 -- 17}, abstract = {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.}, language = {en} } @article{SavelievBelyaevaChashinetal., author = {Saveliev, Dmitry V. and Belyaeva, Inna A. and Chashin, Dmitri V. and Fetisov, Leonid Y. and Shamonin (Chamonine), Mikhail}, title = {Large Wiedemann effect in a magnetoactive elastomer}, series = {Journal of Magnetism and Magnetic Materials}, volume = {511}, journal = {Journal of Magnetism and Magnetic Materials}, number = {October}, publisher = {Elsevier}, doi = {10.1016/j.jmmm.2020.166969}, abstract = {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.}, language = {en} } @article{AndersBriemNovaketal., author = {Anders, M. and Briem, Ulrich and Novak, G. and Steinbach, G.}, title = {Inspektionsintervalle im Blick}, series = {Technische Logistik}, journal = {Technische Logistik}, publisher = {Huss-Medien}, address = {Berlin}, pages = {14 -- 17}, language = {de} } @article{BrockKoderRabletal., author = {Brock, Damian and Koder, Alexander and Rabl, Hans-Peter and Touraud, Didier and Kunz, Werner}, title = {Optimising the biodiesel production process: Implementation of glycerol derivatives into biofuel formulations and their potential to form hydrofuels}, series = {Fuel}, volume = {264}, journal = {Fuel}, number = {March}, publisher = {Elsevier}, doi = {10.1016/j.fuel.2019.116695}, abstract = {A new biofuel concept is developed, enabling the usage of vegetable oils and glycerol derivatives in mixtures with biodiesel. This concept significantly enhances the biodiesel production's profitability and thus strongly contributes to the sustainability of future biofuels. After simple addition reactions with building block chemicals, less hydrophilic glycerol derivatives are obtained, which are compatible with biofuels. Even more, the products of the reactions of glycerol with acetone or butyric acid, referred to as solketal and tributyrin, respectively, lead to promising biofuels in mixtures with rapeseed oil and its biodiesel. Due to their low freezing points, they act as cloud and freezing point depressants, when added to vegetable oil/biodiesel blends. Further, since their viscosity is close to common biodiesel, biofuels containing high amounts of vegetable oil and even more glycerol derivatives than they arise during the biodiesel production can be obtained. Thus, this new class of biofuels enables adaptable compositions depending on the application and also the usage as drop-in fuel without any or just few percent of further additives. After optimising the formulations, ignition delay, exhaust gas recirculation, fuel consumption and combustion process measurements were performed in an unmodified upto-date diesel engine. The experiments showed that the properties of the formulated biofuels are either similar to or even better than diesel. The hydrotropy of the glycerol derivatives in these mixtures enables the potential to implement water into biofuels, so-called hydrofuels, reducing nitrogen oxide emissions and leading to further optimised dropin fuels.}, language = {en} } @article{FrazzicaBrancatoDawoud, author = {Frazzica, Andrea and Brancato, Vincenza and Dawoud, Belal}, title = {Unified Methodology to Identify the Potential Application of Seasonal Sorption Storage Technology}, series = {Energies}, volume = {13}, journal = {Energies}, number = {5}, publisher = {MPDI}, address = {Basel}, doi = {10.3390/en13051037}, pages = {1 -- 17}, abstract = {In this study, the definition of a new methodology for a preliminary evaluation of the working boundary conditions under which a seasonal thermal energy storage (STES) system operates is described. The approach starts by considering the building features as well as the reference heating system in terms of solar thermal collectors' technology, ambient heat sinks/source, and space heating distribution systems employed. Furthermore, it is based on a deep climatic analysis of the place where the STES needs to be installed, to identify both winter and summer operating conditions. In particular, the STES energy density is evaluated considering different space heating demands covered by the STES (ranging from 10\% up to 60\%). The obtained results demonstrate that this approach allows for the careful estimation of the achievable STES density, which is varies significantly both with the space heating coverage guaranteed by the STES as well as with the ambient heat source/sink that is employed in the system. This confirms the need for careful preliminary analysis to avoid the overestimation of the STES material volume. The proposed approach was then applied for different climatic conditions (e.g., Germany and Sweden) and the volume of one of the most attractive composite sorbent materials reported in the literature, i.e., multi-wall carbon nanotubes (MWCNT)-LiCl, using water as the working fluid, needed for covering the variable space heating demand in a Nearly Zero Energy Building (NZEB) was calculated. In the case of Swedish buildings, it ranges from about 3.5 m3 when 10\% of the space heating demand is provided by the STES, up to 11.1 m3 when 30\% of the space heating demand is provided by the STES.}, language = {en} } @inproceedings{SchiedermeierRettnerSteineretal., author = {Schiedermeier, Maximilian and Rettner, Cornelius and Steiner, Marcel and M{\"a}rz, Martin}, title = {Dual-inverter control synchronization strategy to minimize the DC-link capacitor current}, series = {2020 IEEE Vehicle Power and Propulsion Conference (VPPC), 18 November 2020 - 16 December 2020, Gijon, Spain}, booktitle = {2020 IEEE Vehicle Power and Propulsion Conference (VPPC), 18 November 2020 - 16 December 2020, Gijon, Spain}, publisher = {IEEE}, doi = {10.1109/VPPC49601.2020.9330921}, pages = {1 -- 6}, abstract = {This paper proposes the possible switching synchronization strategies of an automotive dual-inverter against the background of minimizing the RMS DC-link capacitor current. The publication mainly focuses on the straight-ahead motion of a rear axle with one electric drive per wheel. In addition to it, a dual-inverter consisting of two subinverters with a common DC-link capacitor is taken into consideration. These sub-inverters each have three phases and are based on a 2-level voltage-source-topology. To control the electrical machines, the continuous Space-Vector-Modulation strategy is used. For this application, different control signal synchronization strategies of the two sub-inverters of the dualinverter are presented. Apart from the existing strategies, this paper proposes a new method, which inherits a compromise between low complexity and high effectiveness. In contrast to previous publications, the resulting capacitor currents are quantified and subsequentlyevaluated. This novel quantification, which is dependent on the dual-inverter's operating point, provides a base for targeted dimensioning of the capacitor. Moreover, this forms the foundation for further investigations of vehicle's cornering, as well as for the possible synchronization of stand-alone inverters. In the context of this publication, the presented results are verified by experimentally determined data of a motor-inverter system.}, language = {en} } @article{ChatzitakisSafarovOpferkuchetal., author = {Chatzitakis, Paris and Safarov, Javid and Opferkuch, Frank and Dawoud, Belal and Hassel, Egon}, title = {Vapor pressures and activity coefficients of 2,2,2-trifluoroethanol in binary mixtures with 1,3-dimethyl-2-imidazolidinone and 2-pyrrolidone}, series = {Journal of Molecular Liquids}, volume = {305}, journal = {Journal of Molecular Liquids}, number = {May}, publisher = {Elsevier}, issn = {0167-7322}, doi = {10.1016/j.molliq.2020.112828}, abstract = {The vapor pressures of two binary mixtures containing 2-trifluoroethanol (TFE) + 1,3-dimethyl-2-imidazolidinone (DMI) and TFE + 2-pyrrolidone (PYR), were investigated at temperatures T = (274.15 to 423.15) K using two different static method installations. Both combinations were modelled using an extended Clausius-Clapeyron equation with concentration dependent parameters and the NRTL equation with temperature dependent parameters. The best fit was obtained using the NRTL equation.}, language = {en} } @article{HaslbeckBrueckl, author = {Haslbeck, Matthias and Br{\"u}ckl, Oliver}, title = {Netzplanung Mittelspannungsnetze: Abbildung eines innovativen Blindleistungsmanagements, Teil 1 und 2}, series = {ew - Magazin f{\"u}r die Energiewirtschaft}, journal = {ew - Magazin f{\"u}r die Energiewirtschaft}, number = {7-8 und 9}, pages = {36 -- 39}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Ohne Speicher, Wasserstoff und Power-to-X keine Dekarbonisierung von Verkehr und Industrie - M{\"o}glichkeiten und Notwendigkeit der integrierten Sektorenkopplung}, series = {CIGRE/CIRED Informationsveranstaltung 2020, Leipzig, 13.10.2020}, journal = {CIGRE/CIRED Informationsveranstaltung 2020, Leipzig, 13.10.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Power-to-Gas technologies in the energy sector and their role in the fight against climate change}, series = {Hungarian Power-to-Gas REKK Forum, Budapest Corvinus University, 12.02.2020}, journal = {Hungarian Power-to-Gas REKK Forum, Budapest Corvinus University, 12.02.2020}, language = {en} } @misc{Sterner, author = {Sterner, Michael}, title = {Die Rolle von Wasserstoff in allen Sektoren}, series = {Sektoren{\"u}bergreifende Erkenntnisse zu PtX Fachforum "Wasserstoff Technologie, Prozesssicherheit und Regionalentwicklung", Kurt-Schwabe-Institut f{\"u}r Mess- und Sensortechnik Meinsberg e.V.) Meinsberg, 23.9.2020}, journal = {Sektoren{\"u}bergreifende Erkenntnisse zu PtX Fachforum "Wasserstoff Technologie, Prozesssicherheit und Regionalentwicklung", Kurt-Schwabe-Institut f{\"u}r Mess- und Sensortechnik Meinsberg e.V.) Meinsberg, 23.9.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland}, series = {Hydrogen Dialogue H2.Bayern, 18.11.2020, N{\"u}rnberg Friedrich-Alexander-Universit{\"a}t}, journal = {Hydrogen Dialogue H2.Bayern, 18.11.2020, N{\"u}rnberg Friedrich-Alexander-Universit{\"a}t}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Bedeutung des Klimaschutzes f{\"u}r die Wirtschaft in Ostbayern}, series = {Veranstaltungsreihe der Freunde der OTH Regensburg e. V., Regensburg, Regensburg 25.11.2020}, journal = {Veranstaltungsreihe der Freunde der OTH Regensburg e. V., Regensburg, Regensburg 25.11.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Vom Klimaschutz zum Wasserstoff in Verkehr und Industrie - jetzt regional handeln}, series = {Kick-Off Workshop: HyExpert Wasserstoffmodellregion Fichtelgebirge, Wunsiedel, 22.09.2020}, journal = {Kick-Off Workshop: HyExpert Wasserstoffmodellregion Fichtelgebirge, Wunsiedel, 22.09.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Wasserstoff als zentraler Baustein der Energiewende in S{\"u}ddeutschland: Powerto- Gas und der rechtliche Rahmen}, series = {1. Wasserstofftag S{\"u}ddeutschland, Um 29.10.2020}, journal = {1. Wasserstofftag S{\"u}ddeutschland, Um 29.10.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Warum wir Power-to-X f{\"u}r die Klimaneutralit{\"a}t und Mobilit{\"a}tswende brauchen}, series = {DECHEMA Fachforum Diesel: Mobilit{\"a}tswende durch alternative Antriebe und Kraftstoffe:, Frankfurt 02.12.2020}, journal = {DECHEMA Fachforum Diesel: Mobilit{\"a}tswende durch alternative Antriebe und Kraftstoffe:, Frankfurt 02.12.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Wasserstoff - Energietr{\"a}ger der Zukunft}, series = {BBA Forum, Passau 24.11.2020}, journal = {BBA Forum, Passau 24.11.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Megathema Wasserstoff: Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland}, series = {IRES Symposium, Berlin 18.11.2020}, journal = {IRES Symposium, Berlin 18.11.2020}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {The role of green H 2 + Power-to-X in the German Energy Transition}, series = {First Brazilian-German Green Hydrogen Congress, Brasilia 06.10.2020}, journal = {First Brazilian-German Green Hydrogen Congress, Brasilia 06.10.2020}, language = {en} }