Fridge magnets
QuickField simulation example
Fridge magnets (refrigerator magnets) are popular application of the Halbach Array. They are designed to increase the magnetic force on one side.
Engineering question
How to find magnetic field of fridge magnets?
Engineering answer
Set up a plane-parallel QuickField DC Magnetics problem for a permanent magnet and evaluate magnetic field distribution from computed field results.
Typical applications
refrigerator permanent magnets, Halbach magnet arrays, decorative magnetic strips
- Download simulation files (files may be viewed using any QuickField Edition).
Problem Type
Plane-parallel problem of DC magnetics
Geometry
Magnet is made from combination of nine triangular prisms (triangle is in the XY plane) arranged into the film 1 mm thick, 20 mm wide.
Given
D = 1 mm,
H = 1 mm,
B = 20 mm,
Magnet material - N35,
Steel fridge door thickness 1 mm, relative magnetic permeability 1000.
Task
Calculate the magnetic field distribution and the magnet attraction force to the fridge door made of steel with the relative magnetic permeability 1000.
Solution
Model may be defined and solved as a DC Magnetic Analysis problem.
Results
Magnetic field of the Halbach array fridge magnet in the empty space.
Magnetic field lines of the Halbach array magnet near the steel fridge door.
Fridge magnet attraction force at distance dx=0.01 mm is f = 95 N.
* References: Wikipedia :: Refrigerator magnet
- Video: Fridge magnets
- View simulation report in PDF