Boundary Type

E-Field Behavior

Used to model...

Default Boundary Conditions (Natural and Neumann)

Field behaves as follows:

• Natural boundaries - The normal and tangent components of J and E are continuous across discontinuity surfaces.
• Neumann boundaries - E and J vectors are tangential to the boundary. Flux cannot cross a Neumann boundary.

Object interfaces are initially set to natural boundaries; outer boundaries are initially set to Neumann boundaries.

Symmetry

Field behaves as follows:

• Even Symmetry (Flux Tangential) - E and J vectors are tangential to the boundary; its normal components are zero.
• Odd Symmetry (Flux Normal) - E and J vectors are normal to the boundary; its tangential components are zero.

Planes of geometric and electrical symmetry.

Matching (Independent and Dependent)

The E-field on the dependent boundary is forced to match the magnitude of the E-field on the independent boundary if the plus sign is used. If the minus sign is used, the field on the dependent boundary will oscillate with opposite phase angle (180 degrees phase shift).

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

Insulating

The current cannot cross the boundary.

Thin, perfectly insulating sheets between touching conductive domains.

Thin Layer

When two parts of the domain are separated by thin volume, it can be modeled by a Thin Layer. This boundary creates a field discontinuity (voltage drop) between the two sides of the selected surface based on the material bulk properties and thickness.

Thin and non-perfect (possibly lossy) domains.