# Describing active solid conductors (3D)

## Classification

In a general approach it is possible to differentiate two types of active solid conductors:

• “open” (ex.: U shaped, or E shaped…)
• “closed” (ex.: toroidal shaped, or…)

These conductors are briefly described hereafter and in more detail in the following paragraphs.

## “Open” solid conductor

An “ open ” solid conductor is a conductor with any shape (See example on the opposite figure)

Attention: The supplied electric terminals of the solid conductor must be on the edge of the domain (symmetry or periodicity plane).

## «Closed» solid conductor

A “ closed ” solid conductor doesn't exist in the real life. A cut is necessary to carry out the connection with the electrical circuit (see figure below).

In Flux 3D, we can model a “closed” solid conductor, superimposing the two electric terminals without a short-circuit.

A “ closed ” solid conductor has its electrical terminals “superimposed” from a geometric point of view. The same geometrical face corresponds to the two terminals of the solid conductor.

Real conductor Closed solid conductor of Flux 3D

## Orientation of the current

The orientation of the current is set by:

• the entering and exiting faces of the current, for open conductors
• an orientation line

for closed conductors

## Disabling eddy currents in 3D solid conductor regions

Solid conductor regions are not available in Magnetostatic applications (neither in Flux 2D, nor in Flux Skew nor in Flux 3D).

However, in Flux 3D, the user may emulate the behavior of a conductor subjected to direct current with a solid conductor region in a Transient or in a Steady State AC application by disabling the evaluation of the induced current component predicted by the finite element formulation. This is accomplished by checking the option Eddy currents not considered during the solving process (only DC current) during the creation of the solid conductor region. Consequently, with this option both skin and proximity effects will not be considered in the resolution.

Disabling eddy currents in a 3D solid conductor may significantly decrease the total resolution time in large projects. The user must, however, use this option with prudence, since it will surely affect the evaluated results.