Plasma and Fusion Research

Volume 11, 2405041 (2016)

Regular Articles

Speedup of Shielding Current Analysis in High-Temperature Superconducting Film: Implementation of H-Matrix Method
Atsushi KAMITANI, Teruou TAKAYAMA, Ayumu SAITOH and Hiroaki NAKAMURA1)
Yamagata University, 4-3-16 Johnan, Yonezawa, Yamagata 992-8510, Japan
National Institute of Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292, Japan
(Received 28 November 2015 / Accepted 3 March 2016 / Published 15 April 2016)


Numerical techniques are proposed for accelerating a linear-system solver appearing in the virtual-voltage method. After the proposed techniques are implemented to a numerical code for analyzing the shielding current density in a high-temperature superconducting film, their performance is numerically evaluated. The results of computations show that, if GMRES is incorporated as a linear-system solver, the speed of the virtual-voltage method will be remarkably enhanced. Moreover, it is also found that the implementation of the H-matrix method to matrix-vector multiplications in GMRES will further improve the speed of the virtual voltage method.


high-temperature superconductor, H-matrix method, Newton method

DOI: 10.1585/pfr.11.2405041


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