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Magnetic resonance
Posted Aug 28, 2014, 4:59 a.m. EDT Low-Frequency Electromagnetics Version 4.2 2 Replies
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Dear all,
I´m new in COMSOL and I´m trying to simulate a cilinder of air where is applied a costant 7T magnetic field. I´m in doubt about the best physics model to use in this simulation: mfnc, mf or mef. I tried all of them, defining the magnetic field along the cilynder axis, and when I use the mef model an electric voltage and inducted currents appear in the air cilynder. I´m not sure that such result is correct, because the air is a good insulation, and there should not be any current or electric potential because I have no eletric charges or variations in the magnetic flux. The other two models do not show any induced current, but they do not use all the Maxwell equation and I guess they shoul be incomplete in term of physical description.
Can you help me? Which is the best model I can use? Im´using COMSOL 4.2 version
Thank you, Vito
I´m new in COMSOL and I´m trying to simulate a cilinder of air where is applied a costant 7T magnetic field. I´m in doubt about the best physics model to use in this simulation: mfnc, mf or mef. I tried all of them, defining the magnetic field along the cilynder axis, and when I use the mef model an electric voltage and inducted currents appear in the air cilynder. I´m not sure that such result is correct, because the air is a good insulation, and there should not be any current or electric potential because I have no eletric charges or variations in the magnetic flux. The other two models do not show any induced current, but they do not use all the Maxwell equation and I guess they shoul be incomplete in term of physical description.
Can you help me? Which is the best model I can use? Im´using COMSOL 4.2 version
Thank you, Vito
2 Replies Last Post Aug 30, 2014, 5:42 a.m. EDT
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Posted:
1 decade ago
Vito,
for just a constant field you can use mfnc. But maybe you want to do more and then it really depends on your application.
Cheers
Edgar
--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
for just a constant field you can use mfnc. But maybe you want to do more and then it really depends on your application.
Cheers
Edgar
--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi Edgar, thank you for your answer.
Actually, I need to put some components inside the cilynder, and they are composed of different materials. like copper, silicon crystals, etc. I want to see the effects of these components on the magnetic field, since the magnetic field is alterated by the iteraction with currents.
This is why I am in doubt about the corret model. I should keep in count the possible currents induced by the magnetic field (this means using the mef or mf model) but the mef model shows currents in the air cilynder and it is not possible...
I hope to be explaned better now, thanks for all the suggestions you could give me.
Best regards,
Vito
Actually, I need to put some components inside the cilynder, and they are composed of different materials. like copper, silicon crystals, etc. I want to see the effects of these components on the magnetic field, since the magnetic field is alterated by the iteraction with currents.
This is why I am in doubt about the corret model. I should keep in count the possible currents induced by the magnetic field (this means using the mef or mf model) but the mef model shows currents in the air cilynder and it is not possible...
I hope to be explaned better now, thanks for all the suggestions you could give me.
Best regards,
Vito