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    NachhaltigMaschinenbau und Mechatronik

    Zeitschriftenartikel

    T. Mull, T. Wagner, Giuseppe Bonfigli, S. Buchholz, Frank Schäfer, E. Schleicher, C. Schuster, M. Sporn

    Safety cases for design-basis accidents in LWRs featuring passive systems

    [In Press]

    Nuclear Engineering and Design, no. Available online 26 February 2021

    2021

    DOI: 10.1016/j.nucengdes.2021.111095

    Abstract anzeigen

    This paper presents results from a series of integral tests performed at Framatome’s INKA test facility in Karlstein (Germany) which simulates a KERENA boiling water reactor (BWR). The scope of the test series was on the behaviour of and interaction between the different passive systems and components under the conditions of extended loss of alternating power (ELAP). These SBO-like conditions were aggravated in three out of four tests by parallel LOCA (Loss of Coolant Accident). The scenarios of all four tests fully correspond to Design Basic Conditions (DBC). They were: main steam line break, feed water line break, reactor pressure vessel (RPV) bottom leak and station blackout (SBO, non-LOCA). In the tests, the passive systems integrated in KERENA and INKA, respectively, have fulfilled their design functions fully satisfactorily and as follows: The Passive Pressure Pulse Transmitter (PPPT) triggered the RPV depressurization without delay. The Emergency Condenser (EC) system removed decay heat along with stored energy from the RPV to the containment. The Containment Cooling Condenser (CCC) system forwarded said power to a heat sink outside of the containment. The passive containment pressure suppression system kept the containment pressure within the design range, partially displacing surplus thermal energy from the drywell to the wetwell, in particular in the early phases after occurrence of LOCA. The passive core flooding system replenished the coolant inventory of the RPV thereby ensuring water levels in the RPV which are fully sufficient for core cooling. Moreover, the systems have cooperated as anticipated by the designers, quietly and without perturbing each other. Hence the test results, which are reported and discussed more in detail within this paper, soundly confirm the underlying design and its passive features. Said tests were carried out as a part of the joint research project EASY (Evidence of Design Basis Accidents Mitigation solely with passive safety Systems), the overarching objective of which was the development and validation of the code system AC2 of GRS (Gesellschaft für Anlagen- und Reaktorsicherheit gGmbH).

    DigitalNachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    M. Metzger, M. Duckheim, M. Franken, H. Heger, Matthias Huber, M. Knittel, T. Kolster, M. Kueppers, C. Meier, D. Most, S. Paulus, L. Wyrwoll, A. Moser, S. Niessen

    Pathways toward a Decarbonized Future—Impact on Security of Supply and System Stability in a Sustainable German Energy System

    Energies, vol. 14, no. 3

    2021

    DOI: 10.3390/en14030560

    Abstract anzeigen

    Pathways leading to a carbon neutral future for the German energy system have to deal with the expected phase-out of coal-fired power generation, in addition to the shutdown of nuclear power plants and the rapid ramp-up of photovoltaics and wind power generation. An analysis of the expected impact on electricity market, security of supply, and system stability must consider the European context because of the strong coupling—both from an economic and a system operation point of view—through the cross-border power exchange of Germany with its neighbors. This analysis, complemented by options to improve the existing development plans, is the purpose of this paper. We propose a multilevel energy system modeling, including electricity market, network congestion management, and system stability, to identify challenges for the years 2023 and 2035. Out of the results, we would like to highlight the positive role of innovative combined heat and power (CHP) solutions securing power and heat supply, the importance of a network congestion management utilizing flexibility from sector coupling, and the essential network extension plans. Network congestion and reduced security margins will become the new normal. We conclude that future energy systems require expanded flexibilities in combination with forward planning of operation.

    NachhaltigMaschinenbau und Mechatronik

    Zeitschriftenartikel

    Giuseppe Bonfigli, S. Buchholz, F. Schäfer, Nadine Kaczmarkiewicz, C. Schuster, M. Sporn

    Safety cases for design-basis accidents in LWRs featuring passive systems Part 2 – Numerical investigations

    Nuclear Engineering and Design, vol. 372, no. February

    2021

    DOI: 10.1016/j.nucengdes.2020.110996

    Abstract anzeigen

    This paper deals with the improvement and validation of numerical tools for the simulation of design basis accidents in nuclear power plants equipped with passive safety systems. Numerical models are implemented in the framework of the 1-D thermal–hydraulic system code ATHLET developed by GRS. Experimental reference data for the validation were obtained at the INKA test facility, a model of the KERENA reactor, reproducing the passive safety systems nearly at full scale. The validation effort focuses firstly on the accuracy of the models for the single passive components, and secondly on the ability of the numerical simulation to reproduce the interaction of all components of the KERENA design under realistic conditions as reproduced in the INKA test facility. Thermal-hydraulic models are presented and validated for two passive components of the KERENA reactor: the passive pressure pulse transmitter and the pressure-controlled flooding valve. Finally, the full model of the INKA facility, including these and other passive components, is discussed and numerical results for simulations reproducing three different design basis accidents are validated by comparison with the corresponding experimental data.

    DigitalNachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    Kueppers. M., S. Paredes Pineda, M. Metzger, Matthias Huber, S. Paulus, H. Heger, S. Niessen

    Decarbonization pathways of worldwide energy systems – Definition and modeling of archetypes

    Applied Energy, vol. 285, no. 01 March 2021

    2021

    DOI: 10.1016/j.apenergy.2021.116438

    Abstract anzeigen

    Energy system models help to find the optimal technology mixes for decarbonization strategies in countries worldwide. To reduce the modeling effort and analyze as many countries as possible, this paper proposes a novel approach of energy system archetypes which can be directly evaluated. These archetypes classify similar countries worldwide independently from their geographic location. Advantages of this idea are the setup of a transferable global database allowing for data reconstruction between countries, market size estimations, and the ability to compare peer countries facing similar challenges. To enable such modeling, a framework is developed in which the archetypes are defined, standardized modeling rules are developed, and the results are evaluated for validation. In a benchmark against simple geographic classifications, the presented clustering approach, which results in 15 archetypes, improves the variance between all countries and their corresponding archetypes by 44% compared to the variance between the countries and their geographic sub-regions. The model results of these archetypes state the need of balancing technologies for the daily cycle of photovoltaic generation and the general importance of flexibility in future decarbonized energy systems. Overall, the results confirm that archetypes are an adequate approach to derive the set of solutions for the decarbonization of worldwide countries.

    NachhaltigAngewandte Naturwissenschaften und Wirtschaftsingenieurwesen

    Zeitschriftenartikel

    A. Hamid, J. Sun, H. Zhang, Thomas Stirner

    Molecular dynamics simulation analysis of helium cluster growth conditions under tungsten surfaces

    Computational Materials Science, vol. 186, no. January

    2021

    DOI: 10.1016/j.commatsci.2020.109994

    Abstract anzeigen

    Molecular dynamics simulations have been performed to study the effects of helium fluxes on helium cluster size underneath tungsten surfaces under bombardment of helium atoms with incident energy 30 100 eV at temperature 300 2100 K. The simulation results show that the helium cluster size depends on the magnitude of the helium flux: at a higher flux, the helium clusters on average form in smaller size in tungsten but with larger number; while the clusters form further away from the surface at a lower flux. The coalescence of He atoms and helium bubbles depends on the tungsten temperature: at elevated temperatures around 2000 K, the incident He atoms in tungsten slow down more rapidly than at 1000 K but the number of vacancies per He cluster is smaller. The incident energy has a strong effect on the retention of helium atoms: The helium retention rate increases with the incident energy, and the helium retention depends weakly on temperature in the low energy range of interest. It is also found that the surface orientation plays an important role not only in determining the depth distribution but also in determining the helium retention and cluster size: at the surface {1 1 0}, the retention rate of helium atoms is the lowest, and at the surface {1 1 1}, the clusters grow easily in the lateral direction. The present simulation results suggest that the {0 0 1} surface is favorable for fuzz growth. The results obtained in the present work provide insight to the reasons why the fuzz only grows within a certain parameter range at the atomic level.

    DigitalAngewandte InformatikTC Freyung

    Zeitschriftenartikel

    J. Trager, L. Kalová, Raphaela Pagany, Wolfgang Dorner

    Warning apps for road safety – a technological and economical perspective for autonomous driving

    [Article submitted]

    International Journal of Human–Computer Interaction

    2021

    Angewandte WirtschaftswissenschaftenInst. GMRC

    Zeitschriftenartikel

    Josef Scherer

    Risikomanagement – Ein Plädoyer – Unverzichtbares Instrument in der Krise

    TRIOLOG - Das Transfermagazin für Wissenschaft, Wirtschaft und Gesellschaft in Ostbayern, vol. 2, no. 4, pp. 32-33

    2020

    Abstract anzeigen

    Die Corona-Krise und ihre wirtschaftlichen Folgen setzen vielen Branchen und Unternehmen in Deutschland wie auch auf der ganzen Welt hart zu. Trotz aller Gefahren und Probleme, mit denen die Unternehmer derzeit konfrontiert sind, sieht der Jurist Prof. Dr. Josef Scherer auch Chancen in der Krise. Der Professor an der Technischen Hochschule Deggendorf (THD) wirbt eindringlich für ein gut aufgebautes und aktiv gelebtes Risikomanagement in den Unternehmen. Dies sei eine grundsätzliche Voraussetzung, um Krisen gut zu meistern. Gleichzeitig schaffe gelebtes Risikomanagement laut Scherer nachhaltige Werte, die wiederum die Widerstandsfähigkeit der Unternehmen in Krisen erhöhen.

    DigitalNachhaltigAngewandte WirtschaftswissenschaftenInst. GMRC

    Zeitschriftenartikel

    Josef Scherer

    Resilienz & Zukunftsfähigkeit: Aktuelle Anforderungen an Unternehmensführung (GRC), Digitalisierung und Nachhaltigkeit

    JMG Journal für Medizin- und Gesundheitsrecht, no. 3, pp. 165-172

    2020

    DigitalGesundAngewandte WirtschaftswissenschaftenInst. GMRC

    Zeitschriftenartikel

    Josef Scherer, Ann-Kathrin Birker

    „Unternehmensführung 4.0“ in der Health-Care- und Pflege-Branche: Der „Ordentliche Kaufmann 4.0“ und sein digitalisiertes Integriertes GRC-Managementsystem:„Das Richtige richtig tun“ in unsicheren Zeiten!

    JMG Journal für Medizin- und Gesundheitsrecht, no. 1, pp. 34-47

    2020

    NachhaltigElektrotechnik und Medientechnik

    Zeitschriftenartikel

    C. Niu, Y. Zhang, Y. Cui, X. Li, W. Liu, W. Ni, H. Fan, N. Lu, Günther Benstetter, G. Lei, D. Liu

    Effect of temperature on the growth and surface bursting of He nano-bubbles in W under fusion-relevant He ion irradiations

    Fusion Engineering and Design, vol. 163, no. Available online 26 December 2020

    2020

    DOI: 10.1016/j.fusengdes.2020.112159

    Abstract anzeigen

    Under fusion-relevant He+ irradiations, the W surface temperature is one of the most important parameters for controlling the fuzz growth over the W divertor targets, which is associated with the surface bursting of He nano-bubbles. Using He reaction rate model in W, we investigate the effect of temperature on the growth and surface bursting of He nano-bubbles under low-energy (100 eV) and large-flux (∼1022/m2⋅s) He+ irradiations. Increasing the irradiation temperature from 750 to 2500 K leads to a significant change in both the radius of He nano-bubbles and He retention. At an elevated temperature, He solute atoms prefer to rapidly diffuse into He nano-bubbles, thus affecting their concentration, growth and surface bursting. The decrease in He retention is attributed to an increase in the hop rate of solute He atoms in the W top layer, resulting in the significant He release from the W surface. The radius and density of He nano-bubbles calculated by our model are consistent with our experimental observation.

    NachhaltigElektrotechnik und Medientechnik

    Zeitschriftenartikel

    W. Ni, Y. Zhang, Y. Cui, C. Niu, L. Liu, H. Fan, Günther Benstetter, G. Lei, D. Liu

    The effect of fusion-relevant He ion flux on the evolution of He nano-bubbles in W

    Plasma Physics and Controlled Fusion, vol. 62, no. 6

    2020

    DOI: 10.1088/1361-6587/ab8242

    Abstract anzeigen

    Based on a He reaction rate model in W, we have analyzed the effect of fusion-relevant He+ flux on the evolution and surface bursting of He nano-bubbles in W. The concentrations of solute He atoms, trapped He atoms, and He nano-bubbles, and the radius of He nano-bubbles have been obtained as a function of depth, He+ dose, and He+ flux. He retentions in W are also calculated as the function of He+ dose and flux. Our modeling shows that the He+ flux varying from 5.0 × 1018 to 5.0 × 1024 m−2centerdots−1 significantly affects the concentration of solute He atoms diffusing in W and trapped He atoms, the evolution of He nano-bubbles, and He retention in W. Both the concentration and radius of He nano-bubbles in W show the dependence on He+ flux, and their surface bursting leads to an increase ($\Delta {A_{b - Burst}}$) in the W surface area, thus the growth of W nano-fuzz. When He+ flux increases 5.0 × 1018 to 5.0 × 1024m−2centerdots−1, the bursting rate of He nano-bubbles is greatly reduced, accompanied by an increase in $\Delta {A_{b - Burst}}$. However, $\Delta {A_{b - Burst}}$ is less dependent on the fusion-relevant He+ flux varying from 9.0 × 1020 to 1.6 × 1022m−2centerdots−1, which is consistent with the measured W nano-fuzz growth by He/D2 plasmas.

    NachhaltigTC Freyung

    Zeitschriftenartikel

    Kristina Wanieck, D. Ritzinger, C. Zollfrank, S. Jacobs

    Biomimetics: teaching the tools of the trade

    FEBS Open Bio, vol. 10, no. 11, pp. 2250-2267

    2020

    DOI: 10.1002/2211-5463.12963

    Abstract anzeigen

    Biomimetics is a known innovation paradigm of the twenty‐first century with significant impact on science, society, economy, and challenges of sustainability. As such, it can be understood as a mindset for creative thinking and as a methodology or technique for effective knowledge transfer between disciplines, mainly biology and technology. As biomimetics is relevant to practitioners in various fields of application, understanding the teaching and training of biomimetics for different audiences is important. With this article, we aim to give a holistic view of teaching and training practices and opportunities. First, we offer a set of learning objectives based on an analysis of various courses worldwide and we give recommendations for the design of future curricula. Second, based on an audience analysis and interviews, we developed a set of personas of the users of biomimetics, and as such, we offer a deeper understanding of their needs for the design of the process, including tools and methods.

    MobilAngewandte Wirtschaftswissenschaften

    Zeitschriftenartikel

    Johannes Klühspies, Martina Hekler

    A Maglev, a Tunnel, a River. On the Delays in the Realiziation of the Tokyo‐Nagoya Maglev Line

    Transportation Systems and Technology, vol. 6, no. 3, pp. 31-42

    2020

    DOI: 10.17816/transsyst20206331‐42.

    Abstract anzeigen

    The Chuo Shinkansen is a Japanese maglev line under construction between Tokyo and Osaka. On a central section of the line, construction has come to a standstill in 2020 for reasons of regional policy. This threatens the completion of the entire line. The article describes some of the interests triggering the underlying conflict. Some of the key points contained in the Japanese solution proposals are summarized. Overall, the opening of the high-speed maglev system is likely to be postponed by several years.

    MobilEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    M. Pillmayer, N. Scherle, C. Pforr, C. Locher, Marcus Herntrei

    Transformation processes in Germany’s health resorts and spas – a three case analysis

    Annals of Leisure Research, vol. 55, no. 2, pp. 1-18

    2020

    DOI: 10.1080/11745398.2020.1765399

    Abstract anzeigen

    Germany’s traditional health resorts and spas have undergone far reaching transformation processes, triggered mainly by health care system reforms that started in the 1990s and resulted in significant cuts to the public funding of traditional restorative ‘Kur’ treatments in these destinations. Consequently, there has been a significant shift towards Germany’s so-called ‘second health care market’, which captures all privately funded health-related products and services. This paper provides an insight into these highly complex transformation processes using three Bavarian health resorts and spas (Bad Birnbach, Bad Füssing and Bad Griesbach) as case examples. Semi-structured interviews with experts from the three destinations offer insight into the structural transition towards the second health care market, including its manifold challenges and opportunities in an emerging health-leisure nexus.

    MobilEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    Katerina Volchek, R. Law, D. Buhalis, H. Song

    Exploring Ways to Improve Personalisation: The Influence of Tourist Context on Service Perception

    e-Review of Tourism Research, vol. 17, no. 5, pp. 1-16

    2020

    Abstract anzeigen

    The heterogeneity and dynamic nature of tourist needs requires an advanced understanding of their context. This study aims to investigate the effects of observable factors of internal and external contexts on tourist perceptions towards personalised information services performance. An exploratory approach is used to test measurement invariance and the moderating effects of personal, travel, technical and social parameters of the tourist context, when applicable. The findings demonstrate that contextual factors motivate tourists to attribute different meanings to the parameters of the service, that have already been personalised for them. Individually developed personalisation design solutions are required for each travel context.

    MobilEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    D. Buhalis, Katerina Volchek

    Bridging marketing theory and big data analytics: The taxonomy of marketing attribution

    International Journal of Information Management, vol. 55, no. Available online 20 October 2020

    2020

    DOI: 10.1016/j.ijinfomgt.2020.102253

    Abstract anzeigen

    The integration of technology in business strategy increases the complexity of marketing communications and urges the need for advanced marketing performance analytics. Rapid advancements in marketing attribution methods created gaps in the systematic description of the methods and explanation of their capabilities. This paper contrasts theoretically elaborated facilitators and the capabilities of data-driven analytics against the empirically identified classes of marketing attribution. It proposes a novel taxonomy, which serves as a tool for systematic naming and describing marketing attribution methods. The findings allow to reflect on the contemporary attribution methods’ capabilities to account for the specifics of the customer journey, thereby, creating currently lacking theoretical backbone for advancing the accuracy of value attribution.

    NachhaltigEuropan Campus Rottal-InnTC Freyung

    Zeitschriftenartikel

    Javier Valdés, Sebastian Wöllmann, Andreas Weber, G. Klaus, Christina Sigl, M. Prem, Robert Bauer, Roland Zink

    A framework for regional smart energy planning using volunteered geographic information

    Advances in Geosciences, vol. 54, no. 10 December 2020, pp. 179-193

    2020

    DOI: 10.5194/adgeo-54-179-2020

    Abstract anzeigen

    This study presents a framework for regional smart energy planning for the optimal location and sizing of small hybrid systems. By using an optimization model – in combination with weather data – various local energy systems are simulated using the Calliope and PyPSA energy system simulation tools. The optimization and simulation models are fed with GIS data from different volunteered geographic information projects, including OpenStreetMap. These allow automatic allocation of specific demand profiles to diverse OpenStreetMap building categories. Moreover, based on the characteristics of the OpenStreetMap data, a set of possible distributed energy resources, including renewables and fossil-fueled generators, is defined for each building category. The optimization model can be applied for a set of scenarios based on different assumptions on electricity prices and technologies. Moreover, to assess the impact of the scenarios on the current distribution infrastructure, a simulation model of the low- and medium-voltage network is conducted. Finally, to facilitate their dissemination, the results of the simulation are stored in a PostgreSQL database, before they are delivered by a RESTful Laravel Server and displayed in an angular web application.

    DigitalFraunhofer AWZ CTMTMaschinenbau und Mechatronik

    Zeitschriftenartikel

    Jochen Hiller

    Computertomographie (CT) senkt Kosten bei der Retourenbearbeitung

    Sensorik-Magazin des Clusters Sensorik Strategische Partnerschaft Sensorik e.V., vol. 99, no. 4, pp. 3-5

    2020

    DigitalFraunhofer AWZ CTMTMaschinenbau und Mechatronik

    Zeitschriftenartikel

    F. Heilmeier, R. Koos, M. Singer, C. Bauer, Peter Hornberger, Jochen Hiller, W. Volk

    Evaluation of Strain Transition Properties between Cast-In Fibre Bragg Gratings and Cast Aluminium during Uniaxial Straining

    Sensors, vol. 20, no. 21

    2020

    DOI: 10.3390/s20216276

    Abstract anzeigen

    Current testing methods are capable of measuring strain near the surface on structural parts, for example by using strain gauges. However, stress peaks often occur within the material and can only be approximated. An alternative strain measurement incorporates fibre-optical strain sensors (Fiber Bragg Gratings, FBG) which are able to determine strains within the material. The principle has already been verified by using embedded FBGs in tensile specimens. The transition area between fibre and aluminium, however, is not yet properly investigated. Therefore, strains in tensile specimens containing FBGs were measured by neutron diffraction in gauge volumes of two different sizes around the Bragg grating. As a result, it is possible to identify and decouple elastic and plastic strains affecting the FBGs and to transfer the findings into a fully descriptive FE-model of the strain transition area.We thus accomplished closing the gap between the external load and internal straining obtained from cast-in FBG and generating valuable information about the mechanisms within the strain transition area.It was found that the porosity within the casting has a significant impact on the stiffness of the tensile specimen, the generation of excess microscopic tensions and thus the formation of permanent plastic strains, which are well recognized by the FBG. The knowledge that FBG as internal strain sensors function just as well as common external strain sensors will now allow for the application of FBG in actual structural parts and measurements under real load conditions. In the future, applications for long-term monitoring of cast parts will also be enabled and are currently under development.

    DigitalFraunhofer AWZ CTMTMaschinenbau und Mechatronik

    Zeitschriftenartikel

    Jochen Hiller, Peter Landstorfer, Philipp Marx, Matthias Herbst

    Evaluation of the impact of faulty scanning trajectories in robot-based x-ray computed tomography

    Measurement Science and Technology, vol. 32, no. 1

    2020

    DOI: 10.1088/1361-6501/abaf2a

    Abstract anzeigen

    X-ray computed tomography (CT) imaging for industrial applications is limited to certain physical conditions to be fulfilled. The size of the measuring object and the accumulated wall thickness are two fundamental conditions. An omission of these conditions by not capturing object attenuation information by the x-ray detector leads to missing data in the 3D reconstruction process and results as a consequence in image degradation and artifacts. Conventional industrial x-ray CT is based on cone-beam projections and circular or helical scanning trajectories using linear axis and a rotary (lift) table. For many inspection tasks on big-sized or unusually shaped objects the physical limits for obtaining a sufficient high image quality are reached very quickly when using conventional CT systems. Industrial six-axis robots offer much more flexibility with respect to the conditions mentioned earlier and can overcome the limitations of conventional scanners. In the present work we characterized an industrial six-axis robot in its working space following ISO 9283 in terms of pose accuracy and pose repeatability. These results are then used to simulate faulty scanning trajectories in terms of pose deviations where a single robot is used as an object manipulator to rotate virtual specimens on a circular trajectory resulting in different (faulty) reconstruction datasets. These datasets are evaluated visually and by using performance parameters and geometrical features in order to determine the reproduction fidelity (performance) of a one arm robot-based CT system depending on different pose errors. With the results obtained it was shown that a robot-based CT system of type B (in our classification scheme) using one robot as object manipulator should be able to reach a spatial resolution power in the range of the voxel size (in our case 200 µm) and smaller (neglecting effects from focal spot size, detector unsharpness from x-ray to light conversation and scatter radiation) if systematic pose errors are compensated using appropriate calibration methods.