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Hey I had a question regarding comsol. I've uploaded the file in question and the problems is as follows. There is an external current density described by the equations below and by the adjacent heat maps in the photos two directions. The summary of what I've uploaded is that there are heat maps in two different directions Current Density in the r and the z, as well as the normalized scalar of the current density. In addition we have a magnetic flux density in the phi direction (which is the direction that I believe that there should be a magnetic field in) which is completely empty. There is also a picture of the 3-d Model since the other maps are in 2-d, just in case anyone wanted to see if it was actually a torroid.
All Files are labeled accordingly. I've also attached the COMSOL file if anyone wanted to do some digging around in that direction.

The problem is that there is current flowing in this torroid in the r and z directions in a manner that should create a B field in the center of the torroid. Are there some electromagnetism/COMSOL mistakes that I'm making is or is the program giving me errors where it shouldn't be (I'm sorry I'm new to COMSOL). I appreciate everyone's help, thank you very much.

Equations:

current_theta*(rad_major-rad_coil)/r*z/sqrt(z^2+(rad_major-r)^2) (r direction)

current_theta*(rad_major-rad_coil)/r*sqrt(1-(z^2/(z^2+(rad_major-r)^2)))*sign(rad_major-r) (z-direction)