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Assigning material (iron, air or...) to the permanent magnet domains in Magnetic Fields (mf) study.

Hi,

I am modeling a generator in which I have used relative velocity of permanent magnets and coils to generate emf.
I have successfully applied magnet properties (magnetization) in the study using a "amper law" . However, to make the system run, I need also to assign a material such as air or iron to magnet domains, otherwise it gives me errors!

Why is that and what material should I use for that?


I have seen in the library model of permanent magnet that in "Magnetic Fields, No Currents(mfnc)" study, no material (air , iron or ...) is assigned to the permanent magnet domains. why in this case the system run the model with no error?

1 Reply Last Post Apr 21, 2013, 2:45 PM EDT
Posted: 5 years ago Apr 21, 2013, 2:45 PM EDT
Hi

when you assign material nodes and define domains associated COSMOL picks the appropriate material proerties (there may be several rewquired) but you can also fully use "user defined" material properties in the phyics fields and fully override the materials nodes, at will

Normally you do not needto define any material to a domain if this domain has all requried material data entries defined in the user definitions so probably in yor case you have some material properties that are defined via the default (hence requires material nodes) and some defined locally.

With magnets you need to define 2 ampere law nodes, one for all except the magnets adn one (or more if different orientation) nodes specifically for the magnets

--
Good luck
Ivar
Hi when you assign material nodes and define domains associated COSMOL picks the appropriate material proerties (there may be several rewquired) but you can also fully use "user defined" material properties in the phyics fields and fully override the materials nodes, at will Normally you do not needto define any material to a domain if this domain has all requried material data entries defined in the user definitions so probably in yor case you have some material properties that are defined via the default (hence requires material nodes) and some defined locally. With magnets you need to define 2 ampere law nodes, one for all except the magnets adn one (or more if different orientation) nodes specifically for the magnets -- Good luck Ivar

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