Boundary Type

H-Field Behavior

Used to model...

Default Boundary Conditions (Natural and Neumann)

Field behaves as follows:

• Natural boundaries — Tangential H and normal B are continuous across surfaces without current density distribution. Tangential H has a jump if the surface has current density distribution.
• Neumann boundaries — Magnetic field is normal to the boundary.

Initially, object interfaces have natural boundaries; outer boundaries, and excluded objects have Neumann boundaries.

Vector Potential

Sets the magnetic vector potential A_z, or rAf, on the boundary. The behavior of H depends on whether A_z or rAf is constant or functional.

Outer boundaries at specific vector potentials; externally applied magnetic fields.

Symmetry

Field behaves as follows:

• Odd Symmetry (Flux Tangential) — Magnetic Field is tangential to the boundary; its normal components are zero.
• Even Symmetry (Flux Normal) — Magnetic Field is normal to the boundary; its tangential components are zero.

Planes of geometric and magnetic symmetry.

Balloon

Models the case where the structure is “infinitely” far away from other magnetic fields, permanent magnets, or current sources.

Magnetically isolated structures.

Matching

(Independent and Dependent)

The Magnetic Field on the dependent boundary is forced to match the magnitude and direction (or the negative of the direction) of the Magnetic Field on the independent boundary.

Planes of symmetry in periodic structures where Magnetic Field is oblique to the boundary.