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Plotting an electric motor (symmetry issues)

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I am trying to model an electric motor using the magnetic fields interface and there are a few issues that I haven't been able to resolve.

I am only modeling a pie slice like piece of the motor, applying symmetry conditions on the boundaries.

1) Is creating an identity pair and then applying the periodic condition the right way to go?

2) When plotting the results I would really like to be able to plot the entire motor. Is there a rotate data set feature or what is the right way to go? The periodic conditions that I am using are antisymmetric so I also need to invert (multiply by -1) half of the rotated datasets, is there an easy way to apply a function to a given data set?

Thank you for your help.

Best Regards,
Mike

5 Replies Last Post 9 mai 2012, 17:14 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 9 mai 2012, 14:51 UTC−4
Hi

there should be a few examples i the model library (there were several in the 3.5, but I havent visited all the new one yet), identity pair is OK if yu are sure that all rotor and stator BCs are really correctly represented with an identity pair. Sometimes its a symmetry or an antisymmetry one would use, all depends.

Yes there are ways tp rotate the results (provided the symmetry is correct to sho a full 3D from a slice, check the results section (right click along your way it's good exercice for the finger, less for your tennis elbow ;)

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Good luck
Ivar
Hi there should be a few examples i the model library (there were several in the 3.5, but I havent visited all the new one yet), identity pair is OK if yu are sure that all rotor and stator BCs are really correctly represented with an identity pair. Sometimes its a symmetry or an antisymmetry one would use, all depends. Yes there are ways tp rotate the results (provided the symmetry is correct to sho a full 3D from a slice, check the results section (right click along your way it's good exercice for the finger, less for your tennis elbow ;) -- Good luck Ivar

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Posted: 1 decade ago 9 mai 2012, 15:45 UTC−4
Thank you for your answer Ivar! So I'm probably doing the symmetry thing correctly. Still can't find out how to rotate my solution set though. I.e I have one quarter of a motor in a 2D solution and I want to recreate the whole motor geomtetry. Two of the four quarters need to have their fields multiplied by -1 to reverse the flow directions (I used anti symmetric boundary conditions).
Thank you for your answer Ivar! So I'm probably doing the symmetry thing correctly. Still can't find out how to rotate my solution set though. I.e I have one quarter of a motor in a 2D solution and I want to recreate the whole motor geomtetry. Two of the four quarters need to have their fields multiplied by -1 to reverse the flow directions (I used anti symmetric boundary conditions).

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 9 mai 2012, 15:56 UTC−4
Hi

I'm not behind my COMSOL WS, but normally in the Results Data Set (and not the Plot) section you can add a mirror section and or rotate sections, you might have to combine several

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Good luck
Ivar
Hi I'm not behind my COMSOL WS, but normally in the Results Data Set (and not the Plot) section you can add a mirror section and or rotate sections, you might have to combine several -- Good luck Ivar

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Posted: 1 decade ago 9 mai 2012, 16:28 UTC−4
I see the Mirror 2D button when I right cklick data sets, but there is no rotate 2D button in my 4.2a as far as I can see. Feels like there really should be one there though. Do you have one in your version?

Mike
I see the Mirror 2D button when I right cklick data sets, but there is no rotate 2D button in my 4.2a as far as I can see. Feels like there really should be one there though. Do you have one in your version? Mike

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 9 mai 2012, 17:14 UTC−4
Hi

you are right there seem to be only a mirror 3D and then a rotate 2D lower down, then you need to mirror N times ;)

--
Good luck
Ivar
Hi you are right there seem to be only a mirror 3D and then a rotate 2D lower down, then you need to mirror N times ;) -- Good luck Ivar

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