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Bias Current Density

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hi!!

I need to generate 1.5 Tesla magnetic flux out of a rectangular block.

what value of current density (J) should i use?

what is the constitutive relation to find the required current density provided you know the amount of flux to be generated?

I am using AC/DC module.

Regards

1 Reply Last Post 26 ott 2012, 14:25 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 26 ott 2012, 14:25 GMT-4
Hi

what about a magnetisation of M of about 2*1.5T/mu0_const [A/m] but only if your magnet is > 4* longer than large, and the Flux is going along the "long side", and if you have one material all around, such as air.

The magnetic flux will never be "constant" as the field lines, by looping around have different path lengths. However if your flux is strongly contained by a soft iron part, and your free air gap is small compared to the magnet length, then you can drop the factor "2"

If you absolutely want a constant flux you can add it as a background value, or do an optimisation to unifomise your B at the magnet otput, but that means also that your magnet has a very special M distribution

--
Good luck
Ivar
Hi what about a magnetisation of M of about 2*1.5T/mu0_const [A/m] but only if your magnet is > 4* longer than large, and the Flux is going along the "long side", and if you have one material all around, such as air. The magnetic flux will never be "constant" as the field lines, by looping around have different path lengths. However if your flux is strongly contained by a soft iron part, and your free air gap is small compared to the magnet length, then you can drop the factor "2" If you absolutely want a constant flux you can add it as a background value, or do an optimisation to unifomise your B at the magnet otput, but that means also that your magnet has a very special M distribution -- Good luck Ivar

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