:orphan:

.. admonition:: Work in Progress
   :class: warning

   This document is still under development and may change frequently.


===========================================
Tangential Magnetic Flux Boundary Condition
===========================================

.. toctree::
   :maxdepth: 1
   :caption: Tangential Magnetic Flux Boundary Condition

The *tangential magnetic flux* enforces the condition:

.. math::

   \mathbf{n} \cdot \mathbf{B} = 0 \quad \text{on} \quad \Gamma_0,

on the boundary :math:`\Gamma_0`. 

This condition is implemented by through a homogeneous Dirichlet condition on the tangential component
on the *magnetic vector potential* :math:`\mathbf{A}_t`. 

.. math::

   \mathbf{n} \times \mathbf{A} = 0. \quad \text{on} \quad \Gamma_0.


This condition is usually required for boundaries where current enters or leaves the domain. Specifically,
when an `Excitation Coil` is defined with an open coil the ports require to have a tangential magnetic flux 
boundary condition assigned.