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Suche nach „[F.] [Schäfer]“ hat 4 Publikationen gefunden
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    NachhaltigF: Maschinenbau 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.

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    Zeitschriftenartikel

    Anton Schmailzl, Johannes Käsbauer, J. Martan, P. Honnerová, F. Schäfer, Maximilian Fichtl, T. Lehrer, L. Prušáková, J. Tesař, J. Skála, M. Honner

    Measurement of core temperature through semi-transparent polyamide 6 using scanner-integrated pyrometer in laser welding

    International Journal of Heat and Mass Transfer, vol. 146, no. January

    2020

    DOI: 10.1016/j.ijheatmasstransfer.2019.118814

    Abstract anzeigen

    Predicting the core temperature during welding is an ambitious aim in many research works. In this work, a 3D-scanner with integrated pyrometer is characterized and used to measure the temperature during quasi-simultaneous laser transmission welding of polyamide 6. However, due to welding in an overlap configuration, the heat radiation emitted from the joining zone of a laser transmission weld has to pass through the upper polymer, which is itself a semi-transparent emitter. Therefore, the spectral filtering of the heat radiation in the upper polymer is taken into account by calibrating the pyrometer for the measurement task. Thermal process simulations are performed to compare the temperature field with the measured temperature signal. The absorption coefficients of the polymers are measured, in order to get precise results from the computation. The temperature signals during welding are in good agreement with the computed mean temperature inside the detection spot, located in the joining area. This is also true for varying laser power, laser beam diameter and the carbon black content in the lower polymer. Both, the computed mean temperature and the temperature signal are representing the core temperature. In order to evaluate the spatial sensitivity of the measurement system, the emitted heat radiation from both polymers is calculated on basis of the computed temperature field. Hereby it is found, that more than 90 percent of the detected heat radiation comes from the joining area, which is a crucial information for contact-free temperature measurement tasks on semi-transparent polymers.

    NachhaltigF: Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    S. Buchholz, W. Klein-Hessling, Giuseppe Bonfigli, Nadine Kaczmarkiewicz, N. Neukam, F. Schäfer, T. Wagner

    The Code System AC2 for the Simulation of Advanced Reactors within the Frame of the German EASY Project

    Proceedings of the 17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-17) [September 3-8, 2017; Qujiang Int’l Conference Center, Xi’an, Shaanxi, China]

    2017

    NachhaltigF: Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    S. Buchholz, A. Schaffrath, Giuseppe Bonfigli, Nadine Kaczmarkiewicz, N. Neukam, F. Schäfer, T. Wagner

    Evidence of Design Basis Accidents Mitigation Solely with Passive Safety Systems within the Frame of the German EASY Project

    Proceedings of the 17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-17) [September 3-8, 2017; Qujiang Int’l Conference Center, Xi’an, Shaanxi, China]

    2017