magnetic field of a straight wire due to static current

Numerical methods and mathematical models of Elmer
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Phlix
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magnetic field of a straight wire due to static current

Post by Phlix » 12 Dec 2018, 20:24

Dear Elmer-community,

I am facing a problem which is very close related to the test case which can be found here:

https://github.com/ElmerCSC/elmerfem/tr ... teady_wire

In fact, it is the same test except for the fact, that I use a different meshed geometry.
I want to compare the magnetic field with the results of the quasi-static case (E.g. Angular frequency =100rad/s) of the Elmer-GUI Tutorial 7 "Magnetic field induced by harmonic current in a wire".

If I use the provided test case with the wire.grd geometry and a desired current of 188.4 A to get the expected magnetic field of 0.037 T everything works fine.

But If I use my meshed geometry I get an implausible B-Field distribution as depicted in Figure.
B-FieldStaticWire.PNG
B-FieldStaticWire.PNG (48.62 KiB) Viewed 908 times
In the .sif I only changed the boundary conditions.

I have applied the boundary conditions by using Gmsh and using the command:
ElmerGrid 2 4 GmshWire

I do not see any difference compared to the test case "mgdyn_steady_wire".

The sif File as well as the geometry are enclosed in this Post as zipFile.
StaticWire.zip
(683.61 KiB) Downloaded 103 times
I highly appreciate if someone could help me.

Best regards,
Phlix

raback
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Re: magnetic field of a straight wire due to static current

Post by raback » 13 Dec 2018, 16:27

Hi Phlix

Nasty little problem in the sif file: You had wrong size of Target Boundaries in the AirSurface. Try with this:

Code: Select all

Boundary Condition 5
  Name = "AirSurface"
  Target Boundaries(4) = 1 2 9 12

  AV {e} 1 = Real 0.0
  AV {e} 2 = Real 0.0
End
-Peter

Phlix
Posts: 11
Joined: 31 Aug 2018, 13:51
Antispam: Yes

Re: magnetic field of a straight wire due to static current

Post by Phlix » 13 Dec 2018, 19:29

Hi Peter,

thank you very much for checking my sif!

Best regards!

Phlix


Ps.
To everyone who is new to Elmer and want to check this case...
Unzip the attached file of the initial post, correct the mentioned mistake of the previous post in the sif file.
With the command prompt in windows go to the unzipped folder.

To execute the solver with the command prompt type:

ElmerSolver case.sif >elmersolver.log

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