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diametric magnet simulation

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I need to simulate a diametric magnet and I'm having a hard time understanding how to setup. How do I set up the magnetic fields? What domain do I use? Should I split the disk in half and use the inside "wall" for that?



1 Reply Last Post Apr 20, 2023, 3:36 a.m. EDT

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Posted: 1 year ago Apr 20, 2023, 3:36 a.m. EDT
Updated: 1 year ago Apr 20, 2023, 3:45 a.m. EDT

You just need to add a Magnet node to your physics, and then use a user defined magnetisation, as shown in the attached file (v6.1), where I have defined the magnetisation with a unit vecor (1,0,0).

If your a plan on looking at how the field changes as the magnet rotates about it's axis, you can use a trigonometric function in the magnetisation definition based on a rotation angle that you can parameterise, for example a unit vector defined as (sin(theta), cos(theta),0). A parametric sweep in this instance will simply rotate the magnetisation and will not require re-meshing for each solution, (much quicker than physically rotating your domain, which would require the mesh to be generated for each solution).

In theory, as your geometry is symmetric, the on axis field would rotate exactly with the magnetisation rotation, and deviation from the ideal can be considered as a model error, which you could minimise by refining your mesh. If your point of interest is slightly off axis, then you would see the "real" error. You want to make sure that the model error is sufficiently smaller than the real error you are looking to determine.

You just need to add a Magnet node to your physics, and then use a user defined magnetisation, as shown in the attached file (v6.1), where I have defined the magnetisation with a unit vecor (1,0,0). If your a plan on looking at how the field changes as the magnet rotates about it's axis, you can use a trigonometric function in the magnetisation definition based on a rotation angle that you can parameterise, for example a unit vector defined as (sin(theta), cos(theta),0). A parametric sweep in this instance will simply rotate the magnetisation and will not require re-meshing for each solution, (much quicker than physically rotating your domain, which would require the mesh to be generated for each solution). In theory, as your geometry is symmetric, the on axis field would rotate exactly with the magnetisation rotation, and deviation from the ideal can be considered as a model error, which you could minimise by refining your mesh. If your point of interest is slightly off axis, then you would see the "real" error. You want to make sure that the model error is sufficiently smaller than the real error you are looking to determine.

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