TY - JOUR A1 - Haug, Sonja A1 - Vetter, Miriam T1 - Altersgerechtes Wohnen im Quartier JF - Standort - Zeitschrift für angewandte Geographie N2 - 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 zukünftige Wohnsituation, den Veränderungsbedarf, den Wunsch nach Gemeinschaftsangeboten und die soziale Einbettung eingegangen. Es zeigt sich eine geringe Veränderungsbereitschaft und ein überdurchschnittlich hohes Maß an lokalem Sozialkapital. Am Ende werden Schlussfolgerungen für das Sanierungs- und Quartiersmanagement gezogen. T2 - Age-appropriate living in the neighborhood KW - Alter KW - Wohnen KW - Stadtviertel KW - Sozialraum KW - Senioren KW - Wohnsituation KW - Sozialraum KW - Lokales Sozialkapital KW - Quartiersgestaltung Y1 - 2021 U6 - https://doi.org/10.1007/s00548-020-00678-3 SN - 1432-220X N1 - Corresponding author: Sonja Haug VL - 45 SP - 11 EP - 17 PB - Springer Nature ER - TY - JOUR A1 - Palomba, Valeria A1 - Nowak, Sebastian A1 - Dawoud, Belal A1 - Frazzica, Andrea T1 - Dynamic modelling of Adsorption systems: a comprehensive calibrated dataset for heat pump and storage applications JF - Journal of energy storage N2 - 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. KW - CHILLERS KW - DIFFUSION KW - ETHANOL ADSORPTION KW - Optimization KW - PERFORMANCE KW - SCALE KW - simulation KW - THERMAL-ENERGY STORAGE KW - TRANSFORMATION KW - WATER-ADSORPTION Y1 - 2021 U6 - https://doi.org/10.1016/j.est.2020.102148 VL - 33 PB - Elsevier ER - TY - JOUR A1 - Sovacool, Benjamin K. A1 - Cabeza, Luisa F. A1 - Pisello, Anna Laura A1 - Colladon, Andrea Fronzetti A1 - Larijani, Hatef Madani A1 - Dawoud, Belal A1 - Martiskainen, Mari T1 - Decarbonizing household heating: Reviewing demographics, geography and low-carbon practices and preferences in five European countries JF - Renewable & Sustainable Energy Reviews N2 - 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. KW - Climate policy KW - Cooling KW - Energy policy KW - Heat decarbonisation KW - Household heat KW - Low-carbon heating KW - Space heating Y1 - 2021 U6 - https://doi.org/10.1016/j.rser.2020.110703 IS - 139 SP - 1 EP - 28 PB - Elsevier ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Diermeier, Andreas A1 - Szecsey, Tamara T1 - Dielectric behaviour of magnetic hybrid materials JF - Physical Sciences Reviews N2 - 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. KW - cappillary doublet KW - diamagnetic KW - elastomer dielectric KW - FTIR KW - interfacial magnetocapacitance KW - magnetoactive polymer KW - PDMS KW - toroid Y1 - 2021 U6 - https://doi.org/10.1515/psr-2019-0121 N1 - Corresponding author: Gareth J. Monkman VL - 7 IS - 10 SP - 1169 EP - 1185 PB - de Gruyter ER - TY - JOUR A1 - Schwanzer, Peter A1 - Schillinger, Maximilian A1 - Mieslinger, Johann A1 - Walter, Stefanie A1 - Hagen, Gunter A1 - Maerkl, Susanne A1 - Haft, Gerhard A1 - Dietrich, Markus A1 - Moos, Ralf A1 - Gaderer, Matthias A1 - Rabl, Hans-Peter T1 - A Synthetic Ash-Loading Method for Gasoline Particulate Filters with Active Oil Injection JF - SAR International Journal of Engines N2 - 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%. KW - Ash KW - GDI KW - GPF KW - Particle Y1 - 2021 U6 - https://doi.org/10.4271/03-14-04-0029 SN - 1946-3936 SN - 1946-3944 VL - 14 IS - 4 SP - 493 EP - 506 PB - SAE International ER - TY - JOUR A1 - Schmidt, Henrik A1 - Straub, Benedikt B. A1 - Sindersberger, Dirk A1 - Bröckel, Ulrich A1 - Monkman, Gareth J. A1 - Auernhammer, Günter T1 - Collision and separation of nickel particles embedded in a Poly dimethylsiloxan matrix under a rotating magnetic field: A strong magneto active function JF - Colloid and Polymer Science N2 - 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. Y1 - 2021 U6 - https://doi.org/10.1007/s00396-020-04784-4 VL - 299 SP - 955 EP - 967 PB - Springer ER - TY - CHAP A1 - Rieger, Anna A1 - Oetjen, Arne A1 - van de Par, Steven A1 - Rabl, Hans-Peter T1 - Gehörbezogene Modellierung der Dissonanz T2 - Tagungsband DAGA 2021: 47. Jahrestagung für Akustik, 15.-18. August 2021, Wien und Online Y1 - 2021 UR - https://www.dega-akustik.de/publikationen/online-proceedings/ VL - 47 SP - 1034 EP - 1037 PB - Deutsche Gesellschaft für Akustik e.V. ER - TY - CHAP A1 - Bauer, Franz A1 - Gawlik, Julia A1 - Sterner, Michael A1 - Hamacher, Thomas ED - Ausfelder, Florian ED - Dura, Hanna T1 - Übergreifende Energiesystemmodellierung T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen – Potentiale. 3. Roadmap des Kopernikus-Projektes P2X, Phase II Y1 - 2021 UR - https://www.kopernikus-projekte.de/lw_resource/datapool/systemfiles/elements/files/CBE2878A53D522EEE0537E695E868061/live/document/DEC_P2X_II_V06_Online_small.pdf SN - 978-3-89746-236-6 SP - 19 EP - 33 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. CY - Frankfurt a.M. ER - TY - JOUR A1 - Lindner, Matthias A1 - Pipa, Andrei V. A1 - Karpen, Norbert A1 - Hink, Ruediger A1 - Berndt, Dominik A1 - Foest, Rüdiger A1 - Bonaccurso, Elmar A1 - Weichwald, Robert A1 - Friedberger, Alois A1 - Caspari, Ralf A1 - Brandenburg, Ronny A1 - Schreiner, Rupert T1 - Icing Mitigation by MEMS-Fabricated Surface Dielectric Barrier Discharge JF - Applied Sciences N2 - Avoiding ice accumulation on aerodynamic components is of enormous importance to flight safety. Novel approaches utilizing surface dielectric barrier discharges (SDBDs) are expected to be more efficient and effective than conventional solutions for preventing ice accretion on aerodynamic components. In this work, the realization of SDBDs based on thin-film substrates by means of micro-electro-mechanical-systems (MEMS) technology is presented. The anti-icing performance of the MEMS SDBDs is presented and compared to SDBDs manufactured by printed circuit board (PCB) technology. It was observed that the 35 mu m thick electrodes of the PCB SDBDs favor surface icing with an initial accumulation of supercooled water droplets at the electrode impact edges. This effect was not observed for 0.3 mu m thick MEMS-fabricated electrodes indicating a clear advantage for MEMS-technology SDBDs for anti-icing applications. Titanium was identified as the most suitable material for MEMS electrodes. In addition, an optimization of the MEMS-SDBDs with respect to the dielectric materials as well as SDBD design is discussed. KW - aerospace engineering KW - anti-icing KW - DBD PLASMA ACTUATORS KW - EXCITATION KW - FLOW-CONTROL KW - low-temperature plasma KW - MEMS KW - SEPARATION CONTROL KW - SDBD Y1 - 2021 U6 - https://doi.org/10.3390/app112311106 N1 - Corresponding author: Matthias Lindner VL - 11 IS - 23 SP - 1 EP - 17 PB - MDPI CY - Basel ER - TY - GEN A1 - Schwanzer, Peter A1 - Dietrich, Markus A1 - Gaderer, Matthias A1 - Rabl, Hans-Peter T1 - Detektion unterschiedlicher Medien in Gasoline Particulate Filter (GPF) mit Hilfe eines Radio-Frequenz (RF-) Sensors T2 - Bayerische Wissenschaftsforum - BayWISS 2020 Y1 - 2020 UR - https://mobilitaet-verkehr.baywiss.de/fileadmin/verbundkolleg/mobilitaet-verkehr/poster/Schwanzer_Peter.pdf ER - TY - BOOK A1 - Altmann, Robert A1 - Gebhard, Jürgen A1 - Emberger, Peter A1 - Thuneke, Klaus A1 - Rabl, Hans-Peter A1 - Remmele, Edgar T1 - Zünd- und Brennverhalten von Pflanzenölkraftstoff und Übertragung auf einen Motor der Abgasstufe V N2 - Durch den Ersatz von Dieselkraftstoff durch Rapsölkraftstoff (R100) können Treibhausgasemissionen reduziert werden. Für einen störungsfreien Betrieb eines Motors mit Rapsölkraftstoff sind jedoch Modifikationen an Motorkomponenten und Motorsteuergerät notwendig, um eine effiziente Verbrennung im Motor zu erreichen. Ziel des Vorhabens ist die Erarbeitung von Grundlagen zur Auslegung der Motorsteuerung pflanzenöltauglicher Offroad-Motoren mit moderner Abgasnachbehandlung mit anschließender entsprechender Abstimmung der Motorapplikation am Prüfstand. Grundlegende Untersuchungen der physikalischen Prozessabläufe von R100 bei der Einspritzung werden an einem hydraulischen Druckanstiegsanalysator (HDA) und einer Hochdruck-Hochtemperatur-Kammer (HDHT-Kammer) durchgeführt. Unterschiede im Zünd- und Brennverhalten werden in einer Konstantvolumenbrennkammer untersucht. Abschließend werden die Erkenntnisse am Motorenprüfstand auf einen DEUTZ-Motor übertragen, dessen Einspritzsystem auch bei den grundlegenden Untersuchungen verwendet wurde. Die Ergebnisse zeigen, dass das Einspritzverhalten von R100 eine höhere Sensitivität gegenüber Kraftstofftemperaturvariationen aufweist als Dieselkraftstoff. Bei niedrigen raftstofftemperaturen sind mit R100 ein längerer Öffnungsverzug 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 führen unter anderem die höhere Viskosität und höhere Siedetemperaturen von R100 zu einem schmäleren Spritzwinkel und verzögerter Verdampfung im Vergleich zum Dieselkraftstoff. Eine Erhöhung des Einspritzdrucks und höhere Temperaturen und Drücke in der Brennkammer verbessern die Gemischaufbereitung. Bei Bedingungen von mittlerer und hoher Last ist der Zündverzug von R100 kürzer und das Verbrennungsverhalten ähnlich zum Dieselkraftstoff. Eine geringere Wärmefreisetzung von R100 wird durch den geringeren Heizwert verursacht. Unter Bedingungen von niedriger Last und Motorstart ist ein längerer Zündverzug von R100 im Vergleich zum Dieselkraftstoff festzustellen. Eine Steigerung des Einspritzdrucks und höhere Brennkammerdrücke und -temperaturen führen bei beiden Kraftstoffen zu kürzeren Zündverzügen, der Einfluss dieser Parameter ist jedoch für R100 stärker als für Dieselkraftstoff. Voreinspritzungen führen bei beiden Kraftstoffen zu einer Verkürzung des Zündverzugs der Haupteinspritzung und zu einer geringeren Wärmefreisetzungsrate. Am Motorprüfstand 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 für beide Kraftstoffe ähnlich und es scheint keine Anpassung der Dosierungsstrategie der wässrigen Harnstofflösung notwendig zu sein. Eine Regeneration des Partikelfilters mit R100 war nach Optimierung der Einstellparameter der Drosselklappe möglich. Motorkaltstart und Leerlauf sind herausfordernde Betriebsphasen, die für R100 einer weiteren Optimierung bedürfen. Eine Temperierung von R100 im Injektor auf 50–60 °C sowie eine Kompensation der Einspritzmenge in Abhängigkeit von der Kraftstofftemperatur sind mögliche Verbesserungsmaßnahmen. Zudem kann durch einen früheren Einspritzbeginn von R100 das Verbrennungsverhalten angepasst werden. Die Motorprüfstandsuntersuchungen bestätigen 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 können. Weiterführende Forschungsarbeiten sind im Bereich der Betriebsphasen des Motorkaltstarts und Leerlaufs mit Rapsölkraftstoff nötig, um einen dauerhaft störungsfreien Betrieb in diesen Betriebsphasen zu erreichen. Die erzielten Erkenntnisse deuten darauf hin, dass hier noch viel Verbesserungspotenzial vorhanden ist. KW - Biokraftstoff KW - Brennwert KW - Zündung KW - Motor KW - Rapsöl KW - Motorsteuerung Y1 - 2020 UR - https://www.tfz.bayern.de/mam/cms08/biokraftstoffe/dateien/tfz_bericht_69_evolum_a.pdf SN - 1614-1008 VL - 69 PB - Technologie- und Förderzentrum im Kompetenzzentrum für Nachwachsende Rohstoffe CY - Straubing ER - TY - GEN A1 - Oetjen, Arne A1 - Rieger, Anna A1 - Rabl, Hans-Peter A1 - van de Par, Steven T1 - The role of dissonance in the sound quality perception for electric vehicles T2 - The Journal of the Acoustical Society of America N2 - 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. Y1 - 2020 U6 - https://doi.org/10.1121/1.5147356 VL - 148 IS - 4 PB - Acoustical Society of America ER - TY - CHAP A1 - Walter, Stefanie A1 - Schwanzer, Peter A1 - Hagen, Gunter A1 - Haft, Gerhard A1 - Dietrich, Markus A1 - Rabl, Hans-Peter A1 - Moos, Ralf ED - Tille, Thomas T1 - Hochfrequenzsensorik zur direkten Beladungserkennung von Benzinpartikelfiltern T2 - Automobil-Sensorik 3 N2 - In Folge der Verschärfung der gesetzlichen Abgasnormen wurden für direkt-einspritzende Benzinmotoren Partikelfilter notwendig. Zur Beladungsüberwachung können aufgrund stark unterschiedlicher Rahmenbedingungen die aus Dieselmotoren bekannten Systeme, wie dem Differenzdrucksensor, nur eingeschränkt übernommen werden. Ein hochfrequenzbasiertes Verfahren koppelt mittels Antennen elektromagnetische Wellen in das Filtergehäuse ein, deren Ausbreitungsverhalten durch die dielektrischen Eigenschaften des eingelagerten Rußes beeinflusst wird. Hierdurch kann bei Auswertung von Transmissionsdämpfung oder Resonanzfrequenzen die Rußbeladung direkt detektiert werden. Y1 - 2020 SN - 978-3-662-61259-0 U6 - https://doi.org/10.1007/978-3-662-61260-6_7 SP - 185 EP - 208 PB - Springer Vieweg CY - Berlin ER - TY - GEN A1 - Schwanzer, Peter A1 - Mieslinger, Johann A1 - Rabl, Hans-Peter A1 - Dietrich, Markus A1 - Haft, Gerhard A1 - Walter, Stefanie A1 - Hagen, Gunter A1 - Moos, Ralf A1 - Gaderer, Matthias T1 - Monitoring of a Particulate Filter for Gasoline Direct Injection Engines with a Radio-Frequency-Sensor T2 - 11th International Exhaust Gas and Particulate Emissions Forum, 3.-4.3.2020, Ludwigsburg, Germany N2 - 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. Y1 - 2020 UR - https://eref.uni-bayreuth.de/54655/ N1 - Projekttitel: Load Sensor for GPF; Projekt-ID: AZ-1288-17 ER - TY - JOUR A1 - Briem, Ulrich T1 - Die neue VDI 2500 : Faserseilwissen kompakt JF - Logistik für Unternehmen N2 - Die Richtlinie VDI 2500 „Faserseile“ hat 1990 erstmals zusammenfassend den Stand der Technik auf dem Gebiet der Faserseile dargestellt und wertvolle Infor-mationen über Aufbau, Auswahl, Konfek-tionierung und Überwachung von Faser-seilen gegeben. Die jetzt erscheinende zweite Auflage enthält eine Vielzahl wichtiger technischer Neuerungen für die Praxis. Zu nennen sind hier die hochfesten Fasern und deren Beschichtung sowie die erstmals systematisch aufgeführten Sei-lendverbindungen und ein Ausblick auf die zukünftig bedeutsamen sogenannten Hybridseile. Eine Checkliste hilft bei der richtigen Auswahl und Bemessung von Faserseilen. Bei den Normen wurde – soweit möglich – auf europäische Normen verwiesen. Y1 - 2020 UR - https://elibrary.vdi-verlag.de/10.37544/0930-7834-2020-11-12-36/faserseilwissen-kompakt-jahrgang-34-2020-heft-11-12?page=1 IS - 11-12 SP - 36 EP - 37 ER - TY - JOUR A1 - Briem, Ulrich T1 - Umlaufbiegewechselzahl von verdichteten Seildrähten JF - Draht Y1 - 2020 UR - https://umformtechnik.net/draht/Inhalte/Aus-der-Forschung/Umlaufbiegewechselzahl-von-verdichteten-Seildraehten IS - 6 SP - 14 EP - 15 ER - TY - JOUR A1 - Schroll-Decker, Irmgard T1 - Rezension zu: Ethik des Wissens. Freiheit und Verantwortung der Wissenschaft in Zeiten des Klimawandels. oekom Verlag (München) 2019. ISBN 978-3-96238-163-9 JF - socialnet Rezensionen Y1 - 2020 UR - https://www.socialnet.de/rezensionen/26341.php SN - 2190-9245 ER - TY - JOUR A1 - Romeis, Dirk A1 - Kostrov, Sergei A. A1 - Kramarenko, Elena Yu A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail A1 - Saphiannikova, M. T1 - Magnetic-field-induced stress in confined magnetoactive elastomers JF - Soft Matter N2 - We present a theoretical approach for calculating the state of stress induced by a uniform magnetic field in confined magnetoactive elastomers of arbitrary shape. The theory explicitly includes the magnetic field generated by magnetizable spherical inclusions in the sample interior assuming a non-linear magnetization behavior. The initial spatial distribution of particles and its change in an external magnetic field are considered. This is achieved by the introduction of an effective demagnetizing factor where both the sample shape and the material microstructure are taken into account. Theoretical predictions are fitted to the stress data measured using a specifically designed experimental setup. It is shown that the theory enables the quantification of the effect of material microstructure upon introducing a specific microstructural factor and its derivative with respect to the extensional strain in the undeformed state. The experimentally observed differences between isotropic and anisotropic samples, compliant and stiff elastomer matrices are explained. Y1 - 2020 U6 - https://doi.org/10.1039/D0SM01337D VL - 16 IS - 39 SP - 9047 EP - 9058 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Geilfuß, Kristina A1 - Dawoud, Belal T1 - Analytical investigation of a zeolite-NaY-water adsorption heat and cold storage and its integration into a steam power process JF - Energy N2 - 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. Y1 - 2020 U6 - https://doi.org/10.1016/j.energy.2020.116977 VL - 195 IS - March PB - Elsevier ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Yuskevich, Pavel T1 - Effective medium theory for the elastic properties of composite materials with various percolation thresholds JF - Materials N2 - 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. KW - elastic properties KW - effective medium approximation KW - self-consistent KW - random heterogeneous medium KW - two-phase composite material KW - percolation threshold Y1 - 2020 U6 - https://doi.org/10.3390/ma13051243 VL - 13 IS - 5 SP - 1 EP - 19 PB - MPDI CY - Basel ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Yuskevich, Pavel A1 - Saveliev, Dmitry V. A1 - Belyaeva, Inna A. T1 - Induced anisotropy in composite materials with reconfigurable microstructure: Effective medium model with movable percolation threshold JF - Physica A: Statistical Mechanics and its Applications N2 - In composite materials, with field-dependent restructuring of the filler material (changes in the mutual arrangement of inclusions), the presence of an external magnetic field induces anisotropy of the dielectric properties, even if the composite is isotropic in the absence of an external field. A modified effective medium approximation is proposed for the calculation of the components of effective permittivity within a class of composites with reconfigurable microstructure, where both phases (the filler and the matrix) are isotropic and the inclusions have spherical shape. The effective physical properties are calculated in the parallel and perpendicular directions to an applied field. The appearance of the anisotropy of the permittivity is simulated by the introduction of two not-equal, possibly variable (field-dependent) percolation thresholds. The implications, of the proposed theoretical approach, are demonstrated for the case of the dielectric properties of magnetoactive elastomers (MAEs). In MAEs with soft polymer matrices, the mutual arrangement of micrometer-sized magnetic inclusions can significantly change in an applied magnetic field. A reasonable agreement between theory and experiment at a measurement frequency of 1 kHz is found, and is improved in comparison to the previous models. The components of the effective permittivity tensor, characterizing the dielectric properties along the direction of the applied magnetic field and in the orthogonal direction, grow with an increasing field. This growth is more pronounced for the permittivity component in the field direction. The possible extensions of the theoretical model and future directions of research are discussed. The presented theoretical approach can be useful for the application-driven development of a number of smart materials, in particular electro- and magnetorheological gels, elastomers and fluids. KW - Effective medium theory KW - Magnetoactive elastomer KW - Percolation threshold KW - Anisotropy KW - Effective permittivity KW - Random heterogeneous medium Y1 - 2020 U6 - https://doi.org/10.1016/j.physa.2020.125170 VL - 560 IS - December PB - Elsevier ER - TY - JOUR A1 - Saveliev, Dmitry V. A1 - Belyaeva, Inna A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Romeis, Dirk A1 - Kettl, Wolfgang A1 - Kramarenko, Elena Yu A1 - Saphiannikova, M. A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail T1 - Giant extensional strain of magnetoactive elastomeric cylinders in uniform magnetic fields JF - Materials N2 - Elongations of magnetoactive elastomers (MAEs) under ascending–descending uniform magnetic fields were studied experimentally using a laboratory apparatus specifically designed to measure large extensional strains (up to 20%) in compliant MAEs. In the literature, such a phenomenon is usually denoted as giant magnetostriction. The synthesized cylindrical MAE samples were based on polydimethylsiloxane matrices filled with micrometer-sized particles of carbonyl iron. The impact of both the macroscopic shape factor of the samples and their magneto-mechanical characteristics were evaluated. For this purpose, the aspect ratio of the MAE cylindrical samples, the concentration of magnetic particles in MAEs and the effective shear modulus were systematically varied. It was shown that the magnetically induced elongation of MAE cylinders in the maximum magnetic field of about 400 kA/m, applied along the cylinder axis, grew with the increasing aspect ratio. The effect of the sample composition is discussed in terms of magnetic filler rearrangements in magnetic fields and the observed experimental tendencies are rationalized by simple theoretical estimates. The obtained results can be used for the design of new smart materials with magnetic-field-controlled deformation properties, e.g., for soft robotics. KW - magnetostriction KW - magnetoactive elastomer KW - extensional strain KW - hysteresis KW - magnetomechanical effect KW - magnetodeformation Y1 - 2020 U6 - https://doi.org/10.3390/ma13153297 SN - 1996-1944 N1 - Corresponding author: Mikhail Shamonin VL - 13 IS - 15 SP - 1 EP - 17 PB - MDPI CY - Basel ER - TY - JOUR A1 - Saveliev, Dmitry V. A1 - Belyaeva, Inna A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Large Wiedemann effect in a magnetoactive elastomer JF - Journal of Magnetism and Magnetic Materials N2 - Large twists of a soft tube (hollow cylinder) in helical magnetic fields are presented for the first time. Such a phenomenon is usually denoted as the Wiedemann effect. The tube is fabricated from a soft magnetoactive elastomer material with the shear modulus of about 56 kPa. The composite material comprises 80 mass% of micrometer-sized iron particles embedded into a polydimethylsiloxane matrix. The circular magnetic field is generated by an electric current in a straight wire passing through the inner hole of the tube. The maximum value of approximately 350″/cm is observed in a longitudinal magnetic field of a few kA/m overlapped with a circumferential magnetic field of about 1.4 kA/m on the surface of the inner hole. A pronounced hysteresis in the dependence of the Wiedemann effect on the circular magnetic field is found. The ways to enhance the Wiedemann twist in magnetoactive elastomers are discussed. The observed large effect is promising for application in magnetic-field controlled torsional actuators, in particular for soft robotics. Y1 - 2020 U6 - https://doi.org/10.1016/j.jmmm.2020.166969 VL - 511 IS - October PB - Elsevier ER - TY - JOUR A1 - Anders, M. A1 - Briem, Ulrich A1 - Novak, G. A1 - Steinbach, G. T1 - Inspektionsintervalle im Blick JF - Technische Logistik Y1 - 2020 SP - 14 EP - 17 PB - Huss-Medien CY - Berlin ER - TY - JOUR A1 - Brock, Damian A1 - Koder, Alexander A1 - Rabl, Hans-Peter A1 - Touraud, Didier A1 - Kunz, Werner T1 - Optimising the biodiesel production process: Implementation of glycerol derivatives into biofuel formulations and their potential to form hydrofuels JF - Fuel N2 - 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. Y1 - 2020 U6 - https://doi.org/10.1016/j.fuel.2019.116695 VL - 264 IS - March PB - Elsevier ER - TY - JOUR A1 - Frazzica, Andrea A1 - Brancato, Vincenza A1 - Dawoud, Belal T1 - Unified Methodology to Identify the Potential Application of Seasonal Sorption Storage Technology JF - Energies N2 - 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. KW - seasonal thermal storage KW - composite sorbents KW - operating conditions Y1 - 2020 U6 - https://doi.org/10.3390/en13051037 VL - 13 IS - 5 SP - 1 EP - 17 PB - MPDI CY - Basel ER - TY - CHAP A1 - Schiedermeier, Maximilian A1 - Rettner, Cornelius A1 - Steiner, Marcel A1 - März, Martin T1 - Dual-inverter control synchronization strategy to minimize the DC-link capacitor current T2 - 2020 IEEE Vehicle Power and Propulsion Conference (VPPC), 18 November 2020 - 16 December 2020, Gijon, Spain N2 - 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. KW - Axles KW - Capacitors KW - Complexity theory KW - DC-link capacitor KW - Dual-inverter KW - interleaved inverters KW - Inverters KW - space vector modulation (SVM) KW - Switches KW - Synchronization KW - Voltage source inverter (VSI) KW - Wheels Y1 - 2020 U6 - https://doi.org/10.1109/VPPC49601.2020.9330921 SP - 1 EP - 6 PB - IEEE ER - TY - JOUR A1 - Chatzitakis, Paris A1 - Safarov, Javid A1 - Opferkuch, Frank A1 - Dawoud, Belal A1 - Hassel, Egon T1 - Vapor pressures and activity coefficients of 2,2,2-trifluoroethanol in binary mixtures with 1,3-dimethyl-2-imidazolidinone and 2-pyrrolidone JF - Journal of Molecular Liquids N2 - 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. KW - 2-Trifluoroethanol KW - 1,3-Dimethyl-2-imidazolidinone KW - 2-Pyrrolidone KW - Vapor pressure KW - NRTL KW - Clausius-Clapeyron Y1 - 2020 U6 - https://doi.org/10.1016/j.molliq.2020.112828 SN - 0167-7322 VL - 305 IS - May PB - Elsevier ER - TY - JOUR A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Netzplanung Mittelspannungsnetze: Abbildung eines innovativen Blindleistungsmanagements, Teil 1 und 2 JF - ew - Magazin für die Energiewirtschaft Y1 - 2020 IS - 7-8 und 9 SP - 36 EP - 39 ER - TY - GEN A1 - Sterner, Michael T1 - Ohne Speicher, Wasserstoff und Power-to-X keine Dekarbonisierung von Verkehr und Industrie – Möglichkeiten und Notwendigkeit der integrierten Sektorenkopplung T2 - CIGRE/CIRED Informationsveranstaltung 2020, Leipzig, 13.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Klimaschutz KW - Energiespeicher KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-Gas technologies in the energy sector and their role in the fight against climate change T2 - Hungarian Power-to-Gas REKK Forum, Budapest Corvinus University, 12.02.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-Gas Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Die Rolle von Wasserstoff in allen Sektoren T2 - Sektorenübergreifende Erkenntnisse zu PtX Fachforum "Wasserstoff Technologie, Prozesssicherheit und Regionalentwicklung", Kurt-Schwabe-Institut für Mess- und Sensortechnik Meinsberg e.V.) Meinsberg, 23.9.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland T2 - Hydrogen Dialogue H2.Bayern, 18.11.2020, Nürnberg Friedrich-Alexander-Universität KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Bedeutung des Klimaschutzes für die Wirtschaft in Ostbayern T2 - Veranstaltungsreihe der Freunde der OTH Regensburg e. V., Regensburg, Regensburg 25.11.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Klimaschutz Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Vom Klimaschutz zum Wasserstoff in Verkehr und Industrie – jetzt regional handeln T2 - Kick-Off Workshop: HyExpert Wasserstoffmodellregion Fichtelgebirge, Wunsiedel, 22.09.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Wasserstoff als zentraler Baustein der Energiewende in Süddeutschland: Powerto- Gas und der rechtliche Rahmen T2 - 1. Wasserstofftag Süddeutschland, Um 29.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Warum wir Power-to-X für die Klimaneutralität und Mobilitätswende brauchen T2 - DECHEMA Fachforum Diesel: Mobilitätswende durch alternative Antriebe und Kraftstoffe:, Frankfurt 02.12.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Wasserstoff – Energieträger der Zukunft T2 - BBA Forum, Passau 24.11.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Megathema Wasserstoff: Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland T2 - IRES Symposium, Berlin 18.11.2020 KW - Erneuerbare Energien KW - Wasserstoff KW - Klimaneutralität KW - Power-to-X KW - Energiewende KW - Sektorenkopplung Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - The role of green H 2 + Power-to-X in the German Energy Transition T2 - First Brazilian-German Green Hydrogen Congress, Brasilia 06.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff KW - Power-to-X Y1 - 2020 ER - TY - CHAP A1 - Hänninen, Risto A1 - Niemetz, Michael A1 - Schoepe, Wilfried T1 - Transition to turbulence in oscillatory superflows T2 - ETC 2013 - 14th European Turbulence Conference 2020: 2 September 2013 - 4 September 2013, Lyon, France N2 - The flow of superfluid helium-4 at very low temperatures around an oscillating microsphere has been studied in detail. At small oscillation amplitudes the drag force is linear in velocity amplitude. Above a critical velocity amplitude vc a transition from potential flow to turbulent flow is signaled by a large and nonlinear drag force that scales as (v2 - v2 c ), where vc is found to be independent of temperature (below 1 K) and of driving force. Interestingly, the critical velocity is found to scale as vc ~ √κω, where κ = h/m ≈ 10−7 m2/s (h is Planck's constant and m is the mass of a helium-4 atom) is the circulation quantum of the superfluid vortices and ω/2π is the oscillation frequency ranging from about 120 Hz to 700 Hz. We also observe slightly above vc that the flow pattern is unstable and switches intermittently between potential flow and turbulence. From time series recorded at constant drive and temperature we have investigated the statistical properties of this switching phenomenon. In this talk the universal law vc ~ √κω will be discussed in detail. It can be derived theoretically in various ways: firstly, from a qualitative but very general argument based on the "superfluid Reynolds number" Rs = vl/κ where v is the flow velocity and l is a characteristic length scale, secondly, and in more detail, from Kopnin's equation of the time dependence of the vortex line density, and, finally, we have obtained this law rigorously by dynamical scaling of the equations of motion of vortex dynamics. Y1 - 2020 UR - http://etc14.ens-lyon.fr/openconf/modules/request.php?module=oc_proceedings&action=view.php&a=Accept&id=17 ER - TY - CHAP A1 - Rieger, Anna A1 - Mühlbauer, Christian A1 - Rabl, Hans-Peter A1 - Weber, Rainer T1 - Dissonanz als Bewertungskriterium multi-tonalen Schalls T2 - Fortschritte der Akustik - DAGA 2020: 46. Deutsche Jahrestagung für Akustik Y1 - 2020 UR - https://www.dega-akustik.de/publikationen/online-proceedings/ SP - 788 EP - 791 PB - Deutsche Gesellschaft für Akustik e.V. ER - TY - CHAP A1 - Mühlbauer, Christian A1 - Rabl, Hans-Peter A1 - Rottengruber, Herrmann ED - Siebenpfeiffer, Wolfgang T1 - Development of a Methodology for Acoustic Analysis and Optimization of Mechatronic Fuel Injection Systems T2 - Automotive Acoustics Conference 2019: Proceedings, 5. Internationale ATZ-Fachtagung Fahrzeugakustik N2 - To identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed that simulates the structure and airborne noise emission. The setup of the system test bench includes an assembly of the acoustical relevant engine parts and an encapsulated drive for the high-pressure pump. A specific control unit enables a high variability for the operation strategy of the injection system. The focus of this study is on the development of a methodology to analyze and optimize the sound quality of gasoline direct injectors in critical operation points by suitable active means. For this, the injection parameters in engine idle have been identified and subsequently transferred to the system test bench. Additionally, the injection parameters have been optimized acoustically and the impacts on the key functions regarding injection rating and shot-to-shot scattering of the injected fuel mass are discussed. Y1 - 2020 SN - 978-3-658-27668-3 U6 - https://doi.org/10.1007/978-3-658-27669-0_15 SP - 211 EP - 225 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael ED - Brinkmann, André ED - Karl, Wolfgang ED - Lankes, Stefan ED - Tomforde, Sven ED - Pionteck, Thilo ED - Trinitis, Carsten T1 - Scalable, Decentralized Battery Management System Based on Self-organizing Nodes T2 - Architecture of computing systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings N2 - Due to the transition to renewable energy sources and the increasing share of electric vehicles and smart grids, batteries are gaining in importance. Battery management systems (BMSs) are required for optimal, reliable operation. In this paper, existing BMS topologies are presented and evaluated in terms of reliability, scalability and flexibility. The decentralisation of BMSs and associated advantages are shown. A scalable, reconfigurable BMS based on a distributed architecture of self-organized, locally controlled nodes is proposed. For distributed system control, producers, batteries and consumers each are equipped with a local microcontroller based control unit, which monitors and controls the local parameters with its own computing and communication resources. Features, advantages and challenges to overcome of the proposed approach are described. KW - Availability Decentralized control KW - Battery management systems KW - Controller Area Network KW - distributed management KW - fault tolerant control KW - Multi-microcomputer system KW - Reconfigurable architectures KW - Renewable energy sources KW - Scalability KW - Topology Y1 - 2020 SN - 978-3-030-52793-8 U6 - https://doi.org/10.1007/978-3-030-52794-5_13 VL - 12155 SP - 171 EP - 184 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Anders, M. A1 - Briem, Ulrich A1 - Novak, G. A1 - Steinbach, G. ED - Katterfeld, André ED - Krause, Friedrich ED - Pfeiffer, Dagmar ED - Richter, Klaus T1 - Neue VDI-Richtlinie für die Seiltriebauslegung T2 - 28. Internationale Kranfachtagung 2020 "Kran 4.0: Potenziale der Digitalisierung", 4. und 5. März 2020, Magdeburg Y1 - 2020 SN - 978-3-947068-08-1 SP - 59 EP - 72 PB - LOGiSCH GmbH CY - Magdeburg ER - TY - CHAP A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Reliability Differentiation and Uniform Risk in Standards BT - a Critical Review and a Practical Appraisal: kriticki pregled i prakticna ocjena T2 - Scientific Symposium Future Trends in Civil Engineering, Zagreb,Croatia, 17 October 2029 N2 - Reliability of structures and infrastructures is a major issue in structural engineering. Structural standards have traditionally been mainly concerned with public safety preventing loss of life or injury; this view has been shifting in recent years towards minimisation of economic loss. This contribution discusses the reliability differentiation principle in modern standards. Its aim is to achieve uniform risk levels for the various classes of structures. Codified criteria for reliability differentiation and risk informed decisions inherent in standards and especially in the Eurocodes are critically reviewed. It is shown that the classification of structures based on consequences of failure is an approach that has not been widely implemented in everyday design. Practical rules for the classification and implementation in design are needed and related proposals are presented. T2 - Razlikovanje pouzdanosti i ujednacenost rizika u propisima Y1 - 2020 U6 - https://doi.org/10.5592/CO/FTCE.2019.11 SP - 241 EP - 260 ER - TY - CHAP A1 - Rösel, Birgit T1 - A concept of a mainly digitalized course on control theory including problembased practical units and digital supported exams T2 - HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain) N2 - This paper decribes the concept of a course on control theory as a minor subject in the department of electrical engineering at the OTH Regensburg. The basis for a new concept is the idea of contructive alignment. The whole teaching module is devided in two blocks. The first block contains the teaching of the knowledge about control theory with an integrated approach for lectures, exercises and practical sessions. In the second block the students attent a practical work package to have the possibility to applicate and deepen their knowledge. To foster active participation the students are asked to document and reflect their work with the course context in an electronic portfolio. The exam of this module consists of three parts with respect to the different competencies obtained during the module. This concept develops not only the knowledge on control theory but personal and social competencies which are of growing interest. The aim of the paper is to present the idea of the concept. Following papers will illustrate the development process and the results obtained later on. Y1 - 2020 U6 - https://doi.org/10.4995/HEAd20.2020.11112 ER - TY - JOUR A1 - Malz, Sebastian A1 - Krenkel, Walter A1 - Steffens, Oliver T1 - Infrared Reflective Wall Paint in Buildings: Energy Saving Potentials and Thermal Comfort JF - Energy and Buildings N2 - The reduction of the energy demand of existing buildings is the main objective of building refurbishment. Managing the heat radiation properties of the wall construction is a possible way to develop highly effective and resource efficient insulation materials and concepts. The application of infrared reflective wall paints and coatings has been studied since the latter half of the 20th century. A brief review of the literature gives an account of the current research status. One has to realise that the conclusions are not uniformly consistent but depend strongly on the specific boundary conditions and investigated parameters. The study presented here discusses the usage of infrared reflective wall paint in conjunction with heat insulation for historic brick masonry. The possible energy savings are linked to the resulting thermal comfort. We identify critical parameters that must be taken into account when using infrared reflective wall paint and derive recommended design rules for the refurbishment of such building types. The findings prove that infrared reflective wall paint can decrease heat losses by 18% and up to 22% if comfort conditions are considered. Increasing energy savings can also cause the negative effect of high radiative asymmetry. Thus, each configuration must be observed in detail. KW - Infrared-reflective KW - Wall paint KW - Coating KW - Existing buildings KW - Radiative asymmetry KW - Energy efficiency Y1 - 2020 U6 - https://doi.org/10.1016/j.enbuild.2020.110212 SN - 0378-7788 VL - 224 IS - October PB - Elsevier ER - TY - JOUR A1 - Schulz, Carsten A1 - Schwarz, Colin T1 - Drivetrain fatigue strength characteristics of model-predictive control for wind turbines JF - Wind Energy N2 - Wind turbines play a crucial role in the revolution towards renewable resources. They need to be economically competitive to be sustainable. This still requires to lower the cost of energy (COE). To this end, nonlinear model predictive control (NMPC) is used within this paper. As known from literature, NMPC significantly improves the energy extracting performance as well as the mitigation of tower loads of wind turbines. As it is shown in this paper, the drivetrain fatigue strength drops disproportionally in parallel, which either increases the demands on the turbine design or decreases the lifetime of drivetrain components. Without additional boundary conditions to the underlying optimal control problems (OCPs), the application of energy-maximizing NMPC might so even raise the COE. Only penalizing axial torque oscillations by quadratic terms decreases energy-extracting performance below the level of classical wind turbine controllers. This makes more sophisticated conditions necessary. In this paper, the increase of the drivetrain damage by NMPC is analyzed, and appropriate boundary conditions are derived, to balance the two contradicting objectives of energy maximization and drivetrain load mitigation. An NMPC approach based on indirect methods is used, to obtain a solution of the OCPs very efficiently. It applies the Hamilton equations and Pontryagin's maximum principle. Its accuracy and efficiency to solve OCPs was presented over the last decades. Y1 - 2020 U6 - https://doi.org/10.1002/we.2520 VL - 23 IS - 12 SP - 2137 EP - 2149 PB - Wiley ER - TY - CHAP A1 - Sippenauer, Thomas A1 - Brückl, Oliver T1 - Verankerung von Flexibilität in der Netzplanung T2 - ScienceLab (begleitender Workshop zur Konferenz Zukünftige Stromnetze: 29.-30. Januar 2020, Berlin) N2 - Im Rahmen des Projektes C/sells wurden mehrere Mittelspannungsnetze modelliert, um die aktuellen Spannungsverhältnisse und Leitungsauslastungen nachbilden zu können. Zudem wurden, angelehnt an den Netzentwicklungsplan, Szenarien für den zukünftigen PV-Zubau und die potenzielle Entwicklung der Elektromobilität entworfen. Auf Basis der Ergebnisse lässt sich eine Netzanalyse hinsichtlich Spannungs- und Stromgrenzwertüberschreitungen sowie zu deren potenziellen Auftrittszeitpunkten und Auftrittsdauern durchführen. Parallel wurde anhand von Sensitivitätsanalysen untersucht, welche Wirksamkeit Flexibilitätseinsätze an den verschiedenen Netzknoten auf den Engpass haben. Dadurch kann bestimmt werden, wie effektiv die verfügbaren, in der Regel örtlich gebundenen Flexibilitätsanbieter eingesetzt werden können. Da die Sensitivitäten arbeitspunktabhängig sind, wurden verschiedene Zeitpunkte im Jahresverlauf berechnet und die jeweilige Änderungen der Wirksamkeit ausgewertet. Neben der Höhe der Leistungsabweichung wurde die Flexibilitätsanforderung auch anhand der Einsatzzeitpunkte und Einsatzdauer sowie anhand der Häufigkeit der nötigen Flexibilitätseinsätze charakterisiert. Aus den gewonnenen Erkenntnissen soll abgeleitet werden, inwiefern sich der flexible Einsatz der Verbrauchsanlagen in der Netzplanung verankern lässt. Besonders relevant ist deshalb, mit welcher Verlässlichkeit die Flexibilität abgerufen werden kann. Eine sehr hohe Verlässlichkeit lässt sich je nach Flexibilitätsanbieter möglicherweise nicht oder nur zu sehr hohen Preisen gewährleisten. Die Eignung der Flexibilitätseinsätze wird somit sowohl aus technischer als auch aus wirtschaftlicher Sicht bewertet. Da eine vollständige Verlässlichkeit ohnehin nicht sichergestellt werden kann (technische Störungen einer Anlage, Wettereinflüsse, etc.), werden auch Fallback-Strategien, z. B. Einspeisespitzenkappung, in die Analyse einbezogen. KW - Netzplanung KW - Flexibilität KW - Netzanalyse Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-55592 SN - 978-3-948176-07-5 SP - 77 EP - 81 PB - Conexio GmbH CY - Pforzheim ER -