Superconducting materials

Superconduc-tivity

Superconducting materials have particular electric and magnetic properties.

In fact, under a certain critical temperature Tc:

  • the resistivity is null
  • the magnetic flux density is null (Meissner effect: the exclusion of the magnetic field from the interior of a material)

Modeling of super-conducting materials

In the case of superconducting materials, the magnetic behavior and the electric behavior are as follows:

  • magnetic behavior (characteristic B(H)): the superconducting material must be considered a hypothetical material with the relative magnetic permeability μr = 0

  • electric behavior (characteristic J(E)): different models can be proposed for the nonlinear electric characteristic J(E)

… in Flux

In Flux, a specific model (power law) is provided for the J(E) characteristic.

In Flux, this model is used only with Transient Magnetic applications (not available in material manager).

Remember: In Steady State AC Magnetic applications, the state variables (potentials) and the results, such as the magnetic field strength and magnetic flux density, have a sinusoidal variation in time. The complex representation is used, and the solution is obtained for only one resolution . That implies linear characteristics of the materials and therefore the model provided for superconducting materials cannot be used with Steady state AC Magnetic applications.