Region: about
Definition
A region is a group of geometric elements of the same type, having the same physical properties.
This definition comprises:
- the concept of the regrouping of the geometric entities
- the concept of the definition of the physical properties
These two concepts are presented in the following sections.
Geometric context
In the context of geometry building, we can distinguish four types of regions, corresponding to the four types of geometric entities: points, lines, faces, volumes.
These four types of regions are presented in the table below.
A region … | regroups a group of … |
---|---|
volume | volumes |
surface | faces |
line | lines |
point | points |
having the same physical properties |
Physical context
In the physical approach, we can distinguish two types of regions: material regions and non-material regions.
These two types of regions are presented in the table below.
A region … | is used to … |
---|---|
material | model a material region |
non-material | impose boundary conditions |
Examples
The material regions are used to model of the material media:
- magnets, magnetic circuits, etc.
- fine air-gaps, thin sheets, etc.
The non-material regions are used to impose boundary conditions:
- normal field crossing a face, etc.
- imposed potential on a line, etc.