# Geometriy description and boundaries of the study domain

## Boundaries of the study domain

The study domain generally differs from a physical application to another.

Indeed:

• for the Steady State AC Magnetic application, the study domain is extended to infinite;
• for the Transient Thermal application, the study domain is limited to the component to be heated of the device

## Boundary conditions

The boundary conditions on the border of each study domain are the following:

• for the Steady State AC Magnetic application, if the infinite box is used, the boundary conditions on the external border are automatically applied;
• for the Transient Thermal application, the boundary conditions are applied on the border of the thermal study domain by means of the regions which allow for the modeling of the thermal exchanges with the surrounding medium.

## Example

The subject is the device of a steel billet induction heating.

This device, depicted in the figure opposite right, is treated in the 2D tutorial “Induction heating”; this is presented in § 2D example: heating of a billet (2D tutorial)

The study domain for each application is depicted in the table below.

Study domain for the magnetic application

Study domain for the thermal application

All regions are active* Light grey regions are inactive**
Note: *A region is called active when the problem considers a solving equation for this region.
Note: **A region is called inactive when the problem does not consider a solving equation for this region