Abstract :
[en] In this paper, we report progress towards a 3D finite element model for the magnetization of a
high-temperature superconductor (HTS): we suggest a method that takes into account a power
law conductivity and demagnetization effects, while neglecting the effects associated with
currents that are not perpendicular to the local magnetic induction. We consider samples that
are subjected to a uniform magnetic field varying linearly with time. Their magnetization is
calculated by means of a weak formulation in the magnetostatic approximation of the Maxwell
equations (A–φ formulation). An implicit method is used for the temporal resolution (backward
Euler scheme) and is solved with the open source solver GetDP. Fixed point iterations are used
to deal with the power law conductivity of HTS. The finite element formulation is validated for
an HTS tube with large n value by comparing with results obtained with other well-established
methods. We show that carrying out the calculations with a single time-step (as opposed to
many small time-steps) produces results with excellent accuracy in a drastically reduced
simulation time. The numerical method is extended to the study of the trapped magnetization of
cylinders that are drilled with different arrays of columnar holes arranged parallel to the
cylinder axis.
Scopus citations®
without self-citations
27
