Example16 Eddy Current Induced on Conductor Shell

General

External AC magnetic field is applied on a conductor shell . Eddy current on the shell is solved.
The vectors of the magnetic field and the magnetic flux density are also solved.
Unless specified in the list below, the default conditions will be applied.

Item	Settings
Solver	Magnetic Field Analysis [Gauss]
Analysis Type	Harmonic analysis
Options	N/A

The frequency is set to 100[Hz] in the harmonic analysis tab. The external magnetic field is directing the Z direction.

Thus, the external magnetic field is set to be AC with the frequency of 100[Hz].

Tabs	Setting Item	Settings
Mesh Tab	Frequency-Dependent Meshing	Surface treatment for conductors: None
Harmonic analysis	Frequency	Minimum: 1×10^2[Hz] Maximum: 1×10^2[Hz]
Harmonic analysis	Step	Linear step: Division number: 0
External magnetic field	External magnetic field	X=0, Y=0, Z=7.95774×10^5[A/m] (=1[Kgauss])

A spherical shell made of copper is placed and the external magnetic field is applied.

The magnetic field is AC as set in the harmonic analysis tab.

Body Number/Type	Body Attribute Name	Material Name
3/Solid	Shell	008_Cu *

* Available from the Material DB

When you set the external magnetic field, select magnetic wall as outer boundary condition.

Boundary Condition Name/Topology	Tab	Boundary Condition Type	Settings
Outer Boundary Condition	Electric	Magnetic wall

The current density on the shell surface is shown.

Eddy current is circulating around the Z axis.

The magnetic field sectioned at YZ plane is shown

The magnetic field is distributed around the shell surface.

There is almost no penetration of the magnetic field into the shell.

The stronger the magnetic filed is, the larger eddy current is.