Numerical simulation of critical current degradation of Nb3Sn strand in CIC conductor

Haruyuki Murakami, Atsushi Ishiyama, Hiroshi Ueda, Norikiyo Koizumi, Kiyoshi Okuno

    Research output: Contribution to journalArticle

    2 Citations (Scopus)

    Abstract

    The critical current of the ITER model coil degraded with an increase in the electromagnetic force. Experiments in which a periodic transverse load was artificially applied to a single coil strand showed this degradation. However, since these experiments were carried out under a certain condition, a general relation between the transverse load and the critical current was not obtained. Therefore, we have developed a numerical simulation code to investigate this general relation. The results of the numerical simulations are in good agreement with the experiments. This indicates that our numerical code is valid for the evaluation of the critical current performance of strands in CIC conductor. Next, the general dependence of the critical current degradation on Ta barrier thickness and resistivity of bronze was evaluated by using the developed simulation code. The results of the calculation showed that the Ta barrier thickness affects the critical current characteristics because of the large flexural rigidity of Ta barrier. On the other hand, the resistivity of bronze and the twist pitch of the filament rarely affect the critical current degradation since current transfers between filaments do not occur within the practical resistivity range of bronze.

    Original languageEnglish
    Article number4510705
    Pages (from-to)1051-1054
    Number of pages4
    JournalIEEE Transactions on Applied Superconductivity
    Volume18
    Issue number2
    DOIs
    Publication statusPublished - 2008 Jun

    Fingerprint

    Critical currents
    strands
    critical current
    conductors
    degradation
    Degradation
    Computer simulation
    Bronze
    bronzes
    transverse loads
    simulation
    electrical resistivity
    filaments
    coils
    Experiments
    rigidity
    Rigidity
    electromagnetism
    evaluation

    Keywords

    • Bending strain
    • CICC
    • Critical current
    • Degradation
    • NbSn strand
    • Numerical simulation

    ASJC Scopus subject areas

    • Electrical and Electronic Engineering
    • Physics and Astronomy (miscellaneous)

    Cite this

    Numerical simulation of critical current degradation of Nb3Sn strand in CIC conductor. / Murakami, Haruyuki; Ishiyama, Atsushi; Ueda, Hiroshi; Koizumi, Norikiyo; Okuno, Kiyoshi.

    In: IEEE Transactions on Applied Superconductivity, Vol. 18, No. 2, 4510705, 06.2008, p. 1051-1054.

    Research output: Contribution to journalArticle

    Murakami, Haruyuki ; Ishiyama, Atsushi ; Ueda, Hiroshi ; Koizumi, Norikiyo ; Okuno, Kiyoshi. / Numerical simulation of critical current degradation of Nb3Sn strand in CIC conductor. In: IEEE Transactions on Applied Superconductivity. 2008 ; Vol. 18, No. 2. pp. 1051-1054.
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