Force Calculation for Magnetic Levitation of a Ferromagnetic Sphere

In this example we calculate the magnetic levitation force of a hollow ferromagnetic sphere placed in a field driven by a current passing through a circular coil. The problem has an analytical solution and we will compare between the two methods.

• The inner radius of the hollow sphere is R1 and its outer radius is R2. The relative permeability of the sphere is mr = 500.
• The coil has a radius of 10 mm and is excited by a current of 20000 A.

The geometry has two planes of symmetry. Thus, we need to model only one quarter of the structure. The whole model is shown below with its surrounding air.

EMS Results

• Magnetic Flux Density

  

• Magnetic Field Intensity

  

• Force Results