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How to couple mf- and mfnc-Physics?

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Dear all,
I want to define material behavior of a permanent magnet via an external function using B(H)-relation. My problem is, that mf-Physics allow H(B)-relation for external functions only. mfnc-Physics however allow B(H) relation for an external function. There's an example for B(H)-relation using mf-and mfnc-Physics, but without any explanation or .mph-File:
www.comsol.com/blogs/accessing-external-material-models-for-magnetic-simulations/
So I'm trying to use for the area around the permanent magnet mf-Physics and for the area of the permanent magnet mfnc-Physics, but I'm not able to couple them correctly. There's already been a thread about that kind of problem ...
www.comsol.de/community/forums/general/thread/10223/
That was six years ago and no one was able to deliver a (real) solution. Now in the present time, that still seems to be an issue. Can anyone help me out? I would be grateful for any kind of support.

Thanks in advance

Michael


1 Reply Last Post 2017年8月8日 GMT-4 05:17

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Posted: 7 years ago 2017年8月8日 GMT-4 05:17
Since no one seems to know, but some one might be interested, I let you know how to couple these Physic-Interfaces ...
The mf-Interphase expects Magnetic Field as input (B(H)-Relation), while the mfnc-Interphase expects Magnetic Fluxdensity as input (H(B)-Relation).
www.comsol.com/model/download/286871/External_Materials_V52_ACDC.pdf PAGE 5
So you have to define for the Interface of both, mf and mfnc, the correct input:
mf: Define Interface-Boundary as Magnetic Field resulting from mfnc-Physics (mfnc.H)
mfnc: Define Interface-Boundary as Magnetic Fluxdensity resulting from mf-Physics (mf.B)
Since no one seems to know, but some one might be interested, I let you know how to couple these Physic-Interfaces ... The mf-Interphase expects Magnetic Field as input (B(H)-Relation), while the mfnc-Interphase expects Magnetic Fluxdensity as input (H(B)-Relation). https://www.comsol.com/model/download/286871/External_Materials_V52_ACDC.pdf PAGE 5 So you have to define for the Interface of both, mf and mfnc, the correct input: mf: Define Interface-Boundary as Magnetic Field resulting from mfnc-Physics (mfnc.H) mfnc: Define Interface-Boundary as Magnetic Fluxdensity resulting from mf-Physics (mf.B)

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