Discussion Forum

Hi

I am trying to calculate the field around a permanent magnet for which I am using the ACDC module with the magnetic field no currents (mfnc) physics. I also have several symmetry planes in my geometry which I would like to utilize to reduce the size of my mesh, but this gives some problems.

What I want to do, is described very nicely here:
www.comsol.com/blogs/exploiting-symmetry-simplify-magnetic-field-modeling/

Boundaries for which n dot B = 0 (surface vector dot field) can be specified with the magnetic insulation boundary condition. Here the field is parallel to the surface.

I can however not figure out how to specify boundaries where n x B = 0 (surface vector cross field), eg. where the field is normal to the surface.

Unfortunately the "perfect magnetic conductor" boundary condition used in the link above, is not available in the mfnc physics. Do you have any suggestions on how to impose the same boundary condition in mfnc, on how to eventually use boundary conditions from mf physics in the mfnc physics (if possible, I am new to this), or if there is some good mathematical reason why this boundary condition is not available in the mfnc physics?

Cheers,
Simon (version 5.1)