WhitneyAV 3D coupled current emag of a coil

Elmer cases by the users for the users
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danielgboyle
Posts: 6
Joined: 24 Oct 2011, 20:26
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WhitneyAV 3D coupled current emag of a coil

Post by danielgboyle » 02 Nov 2011, 00:27

This shows the elmer analysis of a coil embedded in a square volume of air with the following dimensions:

I=12.5 amps
L=62.5 mm
coil DIA=60 mm
wire DIA=12 mm
Number of turns=2.5

See attached images also. Results of Bz on axis are accurate as compared to other FEA codes and formula. Unfortunately I could not upload the vtk output or the elmergrid output files as they exceeded the 2 Mb limit but if you run this example then all of these will be generated.
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WhitneyAV_3d_emag.7z
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pics.zip
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madstamm
Posts: 37
Joined: 07 Apr 2010, 09:56

Re: WhitneyAV 3D coupled current emag of a coil

Post by madstamm » 30 Dec 2011, 00:35

Thank you Daniel!

I made liberal use of your sif file in the example i just posted here:
viewtopic.php?f=3&t=2053

...spend a long time last year trying to get acquainted with Elmer, and playing with the Whitney solver - while Juha was working out the bugs :)

It looks like things are on track to becoming useful for E-M problems.

Mike

madstamm
Posts: 37
Joined: 07 Apr 2010, 09:56

Re: WhitneyAV 3D coupled current emag of a coil

Post by madstamm » 30 Dec 2011, 00:55

Hi Daniel,

I do have a question regarding your example:

I noticed in the sif file that you specify the current in two ways:
1) using "Current Control = Real 12.5 , as well as
2) specifying the potentials at the wire ends, "Potential = 0.001" and "Potential = 0.0" - this, together with the resistance of the coil, also gives the current...

Using (2):
approximating the length of your coil wire to 3 turns, and using length=pi()*D*3, you get about 0.6m of "copper wire".
approximating the 12mm diam to be AWG0000, you get about 0.00008Ohm resistance...
0.001V/0.00008Ohm = 1.25A...

Have you tried turning off the "Current Control" to see if you get the same result?

Mike

danielgboyle
Posts: 6
Joined: 24 Oct 2011, 20:26
Antispam: Yes

Re: WhitneyAV 3D coupled current emag of a coil

Post by danielgboyle » 14 Oct 2013, 22:59

Mike -
Apologies for not replying sooner. I didn't think anyone would be interested in my post. I will try what you suggest and reply.
Regards,
Dan

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