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Hi

but if you are in 3D MF (as I assume) then your torus you have for a dipole, you can force a current via a cylindrical coordinate in the 3D domain. Now if you are not interested in the current distribution in the wire you can exclude that domain from the geoemtry and use your cylindrical coordinates to ensure a constant current density in the boundary

This should work as is, and I believe you will find some models in the model library like that too

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Good luck
Ivar

Hi Ivar

Thanks for the quick reply, but I'm not sure what you mean by forcing a current via cylindrical coordinates. What should I do in detail? Does that mean I should add an External Current Density and assign it to the wire? And does that require using the current density J along a direction instead of the current I?

Thanks again, it means a lot to me.

Hi

if you define a cylindrical coordinate system in the middle of your loop, and add domain or boundary currents, then you can choose this user coordinate system to define your current density along "phi", it's just to avoid to write out the equations to get the current to loop around ;)

What remains useful is to load the initial conditions, and then plot the current with arrows to check that it's really looping around, as it's easy to mix the directions

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Good luck
Ivar

Thanks for the reply, I tried and checked what are talking about. But, if I undestood correctly, the problem is that I don't want to be using the surface density current J, but rather an actual current I, cause I'll be importing its values from measures in a next step.

Actually, I'm more thinking about means such as the "Single coil turn domain " node or "Lumped port" and so on, means I tried but ultimately resulted in errors. And I'm interested in a safe and sure way to reach the simulation of a current excited loop. Have you any ideas about that, please?

Thanks for you attention and help.

Attach your model. This will help to understand your problem.

Hi

certainly you can use "single turn coil" in MF 3D and add an external current along phi of a cylindrical coordinate system. The only thing, external currents are defined as current densities, hence you must calculate (easy ;) the average current density [A/m^2] as I_coil[A] / Coil_Area[m^2] (with in mind that 10[A/mm^2] is about the max you dear to pass into a straight, air-convective cooled 200VAC electric cable, before you start to have serious Joule effects (scale effects allow you higher current densities for much smaller scales

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Good luck
Ivar

Hi,

Ok, I clearly understand what you mean now. I should try that and see if it works. Thank you greatly for you precious help ;)