Choice and definition of the application
Introduction
The first stage corresponds to the choice and the definition of the application.
The two applications are the applications Supplied conductors and Conductors impedance.
The user defines a material (by default).
Reference frequency
In practice, the reference frequency is fixed via the scenario of the solving process. (see § Solving process (according to the scenario)).
The reference frequency is the maximum frequency of the scenario.
Materials
The materials are electric conductive materials characterized by their resistivity in Ω.m.
Only unidirectional conductors of tube type and whose cross-section is rectangular or hollow can be made of a linear homogeneous and isotropic magnetic material characterized by its relative permeability.
The characteristics of available materials are presented in the table below.
| Material | Resistivity (20°C) |
|---|---|
| Aluminum | ρAl = 2,74.10-8 Ω.m |
| Copper | ρCu = 1,72.10-8 Ω.m |
| Gold | ρAu = 2,21.10-8 Ω.m |
| Silver | ρAg = 1,63.10-8 Ω.m |
Skin depth: definition
For a linear homogeneous and isotropic material the average value of “skin” depth, in which the electric currents flow, can be calculated using the following formula:
where:
- f is the frequency
- ρ is the resistivity of the material
- μ0 is the permeability of vacuum; μ0 = 4 π 10-7 H/m
- μr is the relative permeability of the material