Radiation induced currents in mineralinsulated cables and in pick-up coils: model calculations and experimental verification in the BR1 reactor

Research output: Contribution to report/book/conference proceedingsIn-proceedings paper

Authors

Institutes & Expert groups

  • Fusion for Energy

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Abstract

Mineral-insulated (MI) cables and LowTemperature Co-fired Ceramic (LTCC) magnetic pick-up coils are intended to be installed in various position in ITER. The severe ITER nuclear radiation field is expected to lead to induced currents that could perturb diagnostic measurements. In order to assess this problem and to find mitigation strategies models were developed for the calculation of neutron- and gamma-induced currents in MI cables and in LTCC coils. The models are based on calculations with the MCNPX code, combined with a dedicated model for the drift of electrons stopped in the insulator. The gamma induced currents can be easily calculated with a single coupled photon-electron MCNPX calculation. The prompt neutron induced currents requires only a single coupled neutron-photon-electron MCNPX run. The various delayed neutron contributions require a careful analysis of all possibly relevant neutron-induced reaction paths and a combination of different types of MCNPX calculations. The models were applied for a specific twin-core copper MI cable, for one quad-core copper cable and for silver conductor LTCC coils (one with silver ground plates in order to reduce the currents and one without such silver ground plates). Calculations were performed for irradiation conditions (neutron and gamma spectra and fluxes) in relevant positions in ITER and in the Y3 irradiation channel of the BR1 reactor at SCK•CEN, in which an irradiation test of these four test devices was carried out afterwards. We will present the basic elements of the models and show the results of all relevant partial currents (gamma and neutron induced, prompt and various delayed currents) in BR1-Y3 conditions. Experimental data will be shown and analysed in terms of the respective contributions. The tests were performed at reactor powers of 350 kW and 1 MW, leading to thermal neutron fluxes of 1E11 n/cm²s and 3E11 n/cm²s, respectively. The corresponding total radiation induced currents are ranging from 1 to 7 nA only, putting a challenge on the acquisition system and on the data analysis. The detailed experimental results will be compared with the corresponding values predicted by the model. The overall agreement between the experimental data and the model predictions is fairly good, with very consistent data for the main delayed current components, while the lower amplitude delayed currents and some of the prompt contributions show some minor discrepancies.

Details

Original languageEnglish
Title of host publicationEPJ Web of Conferences
Subtitle of host publication5th International Conference on Advancements in Nuclear Instrumentation Measurement Methods and their Applications - ANIMMA 2017
Pages1-7
Number of pages7
Volume170
Edition2018
DOIs
Publication statusPublished - 10 Jan 2018
Event2017 - ANIMMA - Advancements in Nuclear Instrumentation Measurement Methods and their Applications: International Conference on Advancements in Nuclear Instrumentation, Measurement Methods and their Applications - Palais des Congrès, Liège, Belgium
Duration: 19 Jun 201723 Jun 2017
https://www.epj-conferences.org/annima-2017

Publication series

NameEPJ Web of Conferences
PublisherEDP Sciences
ISSN (Print)2100-014X

Conference

Conference2017 - ANIMMA - Advancements in Nuclear Instrumentation Measurement Methods and their Applications
CountryBelgium
CityLiège
Period2017-06-192017-06-23
OtherAdvancements in Nuclear Instrumentation Measurement Methods and their Applications. Application fields: Fundamental physics; Fusion diagnostics and technology; Advanced Nuclear Energy Systems; Research reactors; Nuclear fuel cycle; Decommissioning, dismantling and remote handling; Safeguards, homeland security; Severe accident monitoring; Environmental and medical sciences; Education, training and outreach
Internet address

Keywords

  • ANIMMA 2017, Neutrons, ITER, LTCC pick-up coils, Mineral-insulated cable, Radiation effects

ID: 6776648