Maybe this will help to understand some weirdness of the solver: The "AV" variable is such that vector potential lives on edges (Hcurl space) and scalar potential lives on nodes (H1 space). It is a convention of Elmer that you can request elements with suitable degrees of freedom. The defintion for the lowest order AV solver would be "Element = n:1 e:1" i.e. one dof on node, and one on edge (it is hidded from end-user).

Now, you can only visualize nodal fields (or cell values, but that's another story). Therefore for visualization there is nothing on the solution for the edges. Instead you need to map it from edge field to nodal field. There the CalcFields routine has even keyword "Calculate Magnetic Vector Potential = True'" which does not make sense unless you understand that it asks to map the from Hcurl to H1.

To complicate things when giving Dirichlet BCs the library functionality assigns the default name to the nodal field, whereas you need to use {e} for edge field. So

Code: Select all

```
AV = 0.0 ! sets electric scalar potential to zero
AV {e} = 0.0 ! sets magnetic vector potential to zero
```

-Peter