Induced current problem in COMSOL

AI Thread Summary
The discussion revolves around a user encountering issues with induced current density in COMSOL's ac-dc module while trying to analyze the magnetic field generated by a dipole electrode pair in a conductive environment. The user reports that the total current density approaches zero because the induced current density from the magnetic module counteracts the external current density input. Attempts to mitigate this issue included using different boundary conditions and modules, but results remained consistent with minimal magnetic flux observed primarily at the boundaries. The user seeks advice on preventing COMSOL from generating an induced current density that negates their external input. Effective solutions or adjustments to the simulation setup are requested to resolve this challenge.
peagasus
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Hi everyone,

I'm working on COMSOL's ac-dc module and I'm trying to find the magnetic field which is created by an electrode pair (dipole). The working environment of the pair has nonzero conductivity and relative permittivity.

I first found the current density between the electrodes in the 3D electric module and I tried to take the current density value (ie Jx_emqvw) as the external surce of the induction (magnetic) module. Then I started the solver for both electric and magnetic module. However, total current density becomes nearly zero everytime because the induction currents(magnetic) module creates an induced current density equal to the external current density entered by me (ie Jx_emqvw).

What can I do to prevent COMSOL from creating an induced current density?

I would be very glad for your answers.

Regards,

Emin
 
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I did use the quasi static electromagnetic module before I tried this, and all the magnetic flux is created at the boundary. I thought that it is not much sense and I decided to try both modules seperately.

Also, I tried two boundaries which I take the smaller one as continuity and the larger one as magnetic insulation with infinite elements. So, the results was nearly the same, very small magnetix flux and at the boundaries.

And I forgot to mention, I thought the induced current that I found in the induction currents module was the reason for creating a very small (~1e-12 and 1e-14) magnetix flux by cancelling the external current density I have entered (ie Jx_emqvw).
 
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