Example4 Iron Plate Pulled by Horseshoe Magnet

General

  • A magnetic material is placed near the horseshoe magnet used in Exercise 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.
     

 

Analysis Space

Item

Settings

Analysis Space

3D

Model unit

mm

 

Analysis Conditions

Item

Settings

Solvers

Magnetic Field 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]

Model

A magnetic plate is placed under the horseshoe magnet used in Exercise 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 Attributes and Materials

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: 5×10^3

 

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

Rotational

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.

Boundary Conditions

No setting.

Results

To see the electromagnetic force, go to the [Results] tab

 

 

 click [Table] .

 

 

The magnetic material (Fe) is subjected to 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 bookended 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).