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How to create a homogeneous magnetic field

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Hello everyone,
my goal is to observe the magnetic flux density in an area with a homogeneous magnetic field , dependent on the relative permeability of the walls.
In the beginning i would like to simulate it in 2D, for this i need to create a homogeneous magnetic field outside the magnet itself.
The only solution i was able to produce is:
- a normal magnet defined by Amperes Law and Magnetization
- 2 Rectangles (with a high relative permeability) attached to each side of the magnet
With this a get ~homogeneous magnetic field between the two Rectangles.

So finaly my question: Is it posible to create a normal North and South pole of a magnet, without beeind attached to eachother (for getting my homogeneous magnetic field between them).

In the file attached is my model with the geometries, if i didn`t described it enought.

Best wishes,
Andreas Schneider


4 Replies Last Post 13 sept. 2012, 10:27 UTC−4

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Posted: 1 decade ago 12 sept. 2012, 03:41 UTC−4
Hi,

you can define the homogeneous field at the outer boundary of your model (e.g. B = (0, 0, Bz) for a field in z-direction). This will create a homogeneous field inside the empty domain. Anything magnetic inside the domain will then interact with the field and distort it.. Of course the field will be forced to homgeneity at the outer boundary, so you must make that big enough.

Cheers
Edgar
Hi, you can define the homogeneous field at the outer boundary of your model (e.g. B = (0, 0, Bz) for a field in z-direction). This will create a homogeneous field inside the empty domain. Anything magnetic inside the domain will then interact with the field and distort it.. Of course the field will be forced to homgeneity at the outer boundary, so you must make that big enough. Cheers Edgar

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Posted: 1 decade ago 12 sept. 2012, 08:27 UTC−4
Hello Edgar,
thanks for your advice, do I need to define the field via Ampere´s Law and remanent flux density or am I missing another option to define a magnetic field. I tried to use the "magnetic field" option and adding all 4 outer boundarys to the selection box, but still couldn`t see a magnetic field in my results.

Best wishes,
Andreas Schneider
Hello Edgar, thanks for your advice, do I need to define the field via Ampere´s Law and remanent flux density or am I missing another option to define a magnetic field. I tried to use the "magnetic field" option and adding all 4 outer boundarys to the selection box, but still couldn`t see a magnetic field in my results. Best wishes, Andreas Schneider

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Posted: 1 decade ago 12 sept. 2012, 08:56 UTC−4
Andreas,

defining the magnetic field on the boundaries should do the job.

Cheers
Edgar

Andreas, defining the magnetic field on the boundaries should do the job. Cheers Edgar

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Posted: 1 decade ago 13 sept. 2012, 10:27 UTC−4
Thanks for your time Edgar,

I got it now, after your advice and a little bit more reading i was able to define my magnetic field and can now start to define my experimental setup.

Best wishes,
Andreas
Thanks for your time Edgar, I got it now, after your advice and a little bit more reading i was able to define my magnetic field and can now start to define my experimental setup. Best wishes, Andreas

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