General
Home / Examples / Magnetic Analysis (Gauss, Static Analysis/Harmonic analysis) / Example 4: Magnetic Material Pulled by Horseshoe Magnet
A magnetic material is placed near the horseshoe magnet used in the example 3. It is pulled by the magnet.
The vectors of the magnetic field and the magnetic flux density, and the electromagnetic forces are solved.
Unless specified in the list below, the default conditions will be applied.
Results will vary depending on Femtet version and the PC environment.
Item |
Settings |
Analysis Space |
3D |
Model Unit |
mm |
Item |
Settings |
Solver |
Magnetic Analysis [Gauss] |
Analysis Type |
Static Analysis |
Options |
N/A |
Set the Mesh Tab as follows.
Tab |
Setting Item |
Settings |
Mesh |
Meshing Setup |
Automatically set the general mesh size: Deselect General Mesh Size: 5 [mm] |
A magnetic plate is placed under the horseshoe magnet used in the example 3. There is some gap between the plate and horseshoe magnet.
A solid body of horseshoe magnet consists of 8 parts and each part is defined.
This is because each part has its own magnetizing direction.
Mesh size is set at 0.5 [mm] for both ends of the magnet as the magnetic fields change drastically at both ends.
Set the gap between the bodies and mesh size properly to obtain valid calculation results.
See [Calculation of the Electromagnetic Force] for more details.
Body Number/Type |
Body Attribute Name |
Material Name |
1/Solid |
mag1 |
mag |
2/Solid |
mag2 |
mag |
0/Solid |
mag3 |
mag |
3/Solid |
softmag |
softmag |
* Available from the material DB
The material properties are set up as follows:
Material Name |
Tab |
Properties |
mag |
Permeability |
Material Type: Permanent Magnet |
Magnet |
Magnetization Strength: 0.5 |
|
softmag |
Permeability |
Relative Permeability 5×103 |
The body attributes for mag1 to mag3 are set as follows.
Body Attribute Name |
Tab |
Setting Item |
Settings |
mag1 |
Direction |
Direction Type |
Vector |
Vector |
X=0, Y=0, Z=1 |
||
mag2 |
Direction |
Direction Type |
Circumferential Direction |
Coordinates on Center Axis |
X=0, Y=0.005, Z=0.04 |
||
Vectors of Center Axis |
X=0, Y=1, Z=0 |
||
Direction |
Anticlockwise |
||
mag3 |
Direction |
Direction Type |
Vector |
Vector |
X=0, Y=0, Z=-1 |
The resulting magnetizing directions are as follows.
No setting.
To see the electromagnetic force, go to the [Results] tab
and click [Table] 
.
The magnetic material (Fe) is subjected to about 4.2 [N] magnetic force in the Z direction from the horseshoe magnet.
The vectors of the magnetic field are shown below.
The magnetic field is quite strong in the spaces located between the poles of the magnet and the iron plate.
The vectors of the magnetic flux density are shown below.
The divergence of the magnetic flux density vector is zero everywhere (Maxwell's equations).