Transient A-Phi Formulation Boundaries

The transient A-Phi field solver allows you to define the following types of boundary conditions.

Note: The setup for Insulating, Symmetry, Independent, Dependent, and Resistive Sheet boundaries is the same for both Transient and Transient A-Phi Formulation solvers.

Boundary Type	H-Field Behavior	Used to model...
Default Boundary Conditions (Natural and Neumann)	Field behaves as follows: Natural boundaries –The tangential component of H and the normal component of J are continuous across the boundary. Neumann boundaries – H is normal to the boundary; its tangential components are zero. J field is tangential to the boundary.	Ordinary field behavior. Initially, object interfaces are natural boundaries; outer boundaries, and excluded objects are Neumann boundaries.
Flux Tangential	H is tangential to the boundary and flux cannot cross it.	Problems with flux tangential at outer boundary.
Insulating	Same as Natural boundary, except that current cannot cross the boundary.	Thin, perfectly insulating sheets between touching conductors.
Symmetry	Field behaves as follows: Odd Symmetry (Flux Tangential) – H is tangential to the boundary; its normal components are zero. The potential value at the boundary is zero. Even Symmetry (Flux Normal) – H is normal to the boundary; its tangential components are zero.	Planes of geometric and magnetic symmetry.
Matching (Independent and Dependent)	The H-field on the dependent boundary is forced to match the magnitude and direction (or the negative of the direction) of the H-field on the independent boundary.	Planes of symmetry in periodic structures where H is oblique to the boundary.
Resistive Sheet	Same as Natural boundary.	Voltage drop and loss on the contact surface between two different objects within a conduction path.