A 2-D Robust FE-FV Mixed Method to Handle Strong Nonlinearities in Superconductors

Fac. des Sci., GREEN-INPL, Univ. Henri Poincare, Vandoeuvre-lès-Nancy, France
IEEE Transactions on Magnetics (Impact Factor: 1.42). 09/2010; DOI: 10.1109/TMAG.2010.2044025
Source: IEEE Xplore

ABSTRACT A robust numerical method based on 2-D mixed finite-elements-finite volumes (FE-FV) allows the solution of diffusion problems in superconducting (SC) materials. The proposed approach handles the strong nonlinearity of the E(J) constitutive power law of high-temperature superconductors (HTS). The method is tested for a SC cylinder submitted to a sinusoidal transport current or to a transverse sinusoidal external field. The current density distributions as well as the AC losses are computed. Comparisons to a FE analyses that use the magnetic field as state variable show the validity of the proposed approach. It can be seen that the proposed method is very stable even for large n-values for which the FE method does not converge.

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