Re: Can femm model this?

["David Meeker" <dmeeker@xxxxxxxx>]

--- In femm@xxxxxxxxxxxxxxx, "wigstonmagna" <andrew_ppp@xxxx> wrote:

> But when looking down the axis of the coil (in the z direction let's 
> say), and imagining the plates to extend to +/- infinity in "z", 
> (they are now rectangular), and since any planar cross-section be the 
> same as any other, wouldn't this be OK?
> -Andrew

This isn't a good approximation of your problem. If you take this
cross-section and extend to infinity in the out-of-the-page direction,
there's no end of the coil, so all the flux stays inside the coil. 
Since your "real" coil is finite in extent, and you are specifically
interested in the interactions of the coil with the plates, this isn't
a good approximation.

Also, FEMM only does 2D problems in which the flux flows in the plane
of the screen and current flows in the out-of-the-page direction. 
FEMM doesn't do problems where the flux flows in the out-of-the-page
direction and currents flow in-plane, like we were mentioning above. 
I think MaxwellSV's "Axial Eddy" problem type will solve eddy current
problems where flux travels inthe "out-of-the-page" direction (DC
problems of this type are typically trivial).

Dave
--
David Meeker
http://femm.berlios.de/dmeeker