[Table of Contents]

Plasma and Fusion Research

Volume 10, 3401059 (2015)

Regular Articles

Numerical Investigation on Contactless Methods for Identifying Defects in High-Temperature Superconducting Film
Teruou TAKAYAMA, Atsushi KAMITANI1) and Hiroaki NAKAMURA2)
Department of Informatics, Yamagata University, Yonezawa 992-8510, Japan
1)
Graduate School of Science and Engineering, Yamagata University, Yonezawa 992-8510, Japan
2)
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 25 November 2014 / Accepted 6 April 2015 / Published 27 July 2015)

Abstract

A numerical method has been developed for analyzing the shielding current density in a high-temperature superconducting (HTS) film containing multiple cracks. By using the method, the inductive method and the scanning permanent magnet method for contactlessly measuring the critical current density has been successfully reproduced, and the identifiability of the multiple cracks in the HTS film has been investigated. The results of computations show that, when the cracks are separated from each other, the multiple cracks can be detected individually in the two types of the contactless method. On the other hand, if the crack is pretty close to the interface, the multiple cracks is considered as a single crack. However, the crack position can be detected collectively. Therefore, the contactless methods is useful method for detecting the multiple cracks in an HTS film.

Keywords

multiple crack, critical current density, finite element analysis, numerical simulation, high-temperature superconducting film

DOI: 10.1585/pfr.10.3401059

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Movie

Time evolution of the magnetic flux lines and the shielding current density in an HTS film with a single crack when a magnet is moving from the left edge to the right edge.

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References

  • [1] J.H. Claassen, M.E. Reeves and R.J. Soulen, Jr., Rev. Sci. Instrum. 62, 996 (1991).
  • [2] Y. Mawatari, H. Yamasaki and Y. Nakagawa, Appl. Phys. Lett. 81, 2424 (2002).
  • [3] S.B. Kim, Physica C 463-465, 702 (2007).
  • [4] S. Ohshima, K. Umezu, K. Hattori, H. Yamada, A. Saito, T. Takayama, A. Kamitani, H. Takano, T. Suzuki, M. Yokoo and S. Ikuno, IEEE Trans. Appl. Supercond. 21, 3385 (2011).
  • [5] K. Hattori, A. Saito, Y. Takano, T. Suzuki, H. Yamada, T. Takayama, A. Kamitani and S. Ohshima, Physica C 471, 1033 (2011).
  • [6] T. Takayama and A. Kamitani, IEEE Trans. Appl. Supercond. 23, 9001107 (2013).
  • [7] A. Kamitani, T. Takayama and A. Saitoh, Physica C 504, 57 (2014).
  • [8] T. Takayama and A. Kamitani, IEEE Trans. Appl. Supercond. 24, 9001505 (2014).
  • [9] A. Kamitani and S. Ohshima, IEICE Trans. Electron. E82-C, 766 (1999).
  • [10] A. Kamitani, T. Takayama and S. Ikuno, Physica C 494, 168 (2013).

This paper may be cited as follows:

Teruou TAKAYAMA, Atsushi KAMITANI and Hiroaki NAKAMURA, Plasma Fusion Res. 10, 3401059 (2015).