Discussion Forum

Hey all,

I'm pretty new to COMSOL, but I tried to build a very simple model which has a small, copper wire loop. The hope is that when a current is run through the loop there should be a larger magnetic field in the CENTER of the loop. Unfortunately this sort of "lensing" effect is not observed. I have consulted the model builder files both the current carrying wires model and the helmholtz coil model without being able to figure out whats wrong.

When I define the model I simply draw the parallel wires that bring current, and then a small loop and since I'm using the magnetic fields as my physics I then define the domains that make up the coil as having a current density in x,y,z under external current density. When I solve, I am able to produce a thermal map of the flux but it doesn't seem to make sense, as it implies the highest flux is along the wires and when I change it to magnetic field, it shows some nonsensical surface map that I'm having trouble believing. I would like to be able to produce data of the magnetic field gradient, the magnetic field, the heat produced by the sample when it's running, and the force produced by the wire, but I still haven't been able to make any reasonable results with the model I have. I fear that I may have somehow defined the current density incorrectly, but I'm not sure how. I also tried to build the model in 3D with similar results. I have attached the file, any help is always greatly appreciated.

Regards