Before proceeding with converting a boundary to an interface, it is recommended that you combine any boundaries that belong to the same inter-region surface into one. This will simplify the setup process thereafter by reducing the number of interfaces created.
An illustration showing the before and after boundary setup when a boundary has been converted to an interface is given below:
To convert to an interface, select the boundary or boundaries to be converted and then right-click. In the pop-up menu that appears, select Convert to Interface(s).
This will begin the interface conversion process. Once this is complete, the simulation tree will be updated with the new boundary and interface information.
As can be seen, a copy of the original Surface 1 boundary has been made, in addition to a pair of interface nodes linking the two boundaries. The boundary copy can now be used as part of a new region definition.
A new interface node with the same name as the original boundary will be shown in the Interface node in the simulation tree:
If you examine the Properties window for the new interface node, you will see default Type and Topology settings:
For normal meshing purposes, these settings do not need to be changed.