There is a peculiarity to the problem.
Firstly one would be tempted to dub the problem as axisymmetric i.e you solve in R-Z plane with the excitation currents directed in the theta direction. But THAT IS NOT CORRECT ! the excitation winding does not comply to axisymmetric situation. Strictly speaking, the problem can only be solved in a 3-D formulation.
Secondly, even if your toroidal core has a very very large radius, you still cannot simplify the problem to tackle it as a standard 2-D Cartesian Rectangular co-ordinate system ! This is because the excitation winding does not really exist beyond a finite length whereas the core does.
I would still appreciate if you could spell out your application. May be we can resolve it some other simpler way.
C.Prem Kumar
wilsons@xxxxxxxxxx wrote:
Hi I am a new user of femm and am trying to get a circular donut
magnatized cicumferencely and am having a hard time figuring out how
to do this. I am a senior level college physics student and have
tried everything that I could figure out. Any help in this would be
greatly appreciated. Thanks in advance.
Jason
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