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Difference between normJ and Jphi

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Hello,

in a 2D AC/DC (MF, axisymmetric) study I inetegrat over a coil surrface. (The coil is current driven. I use single turn coil).
When I inegrate over normJ the value ist wrong (not the same I put in the coil)
When I inegrate over Jphi the value is right.

My question: What is the reason for?


Greets
André Dietrich

1 Reply Last Post 2 ago 2012, 13:38 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2 ago 2012, 13:38 GMT-4
Hi

Have you checked the Comsol equation of normJ, and tried a plot of the components ?

Normally, in 2D axi the external current is defined as normal to the paper hence its a pure Jphi, as the norm from my understanding includesalso Jr and Jz too, hence gives potentially a different result.

But as I'm not by my Comsol WS so I cannot check it out myself and one should always carefully check such issues on a simple model where one can write out the results analytically

--
Good luck
Ivar
Hi Have you checked the Comsol equation of normJ, and tried a plot of the components ? Normally, in 2D axi the external current is defined as normal to the paper hence its a pure Jphi, as the norm from my understanding includesalso Jr and Jz too, hence gives potentially a different result. But as I'm not by my Comsol WS so I cannot check it out myself and one should always carefully check such issues on a simple model where one can write out the results analytically -- Good luck Ivar

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