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diamagnetic force calculation
Posted Dec 13, 2011, 9:16 a.m. EST Low-Frequency Electromagnetics Version 4.0 4 Replies
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I'm working on diamagnetic levitation of a little magnet based on the use of both repulsive effect of diamagnetic material like pyrolitic graphite and attrative effect of permanent magnets.
I'd like to run a simple simulation in which i can estimate the "diamagnetic force" applied by a graphite plate on the permanent magnet.
I measured this force experimentally by bringing the magnet close to the graphite plate and measuring the force with a precision balance.
I did a model with COMSOL 4.0 in which i define the magnet by its magnetization (identified with comsol and a teslameter) and the graphite plate by its relative permeability µr.
My problem is when i used the force calculation to evaluate the force (global evalutation) i find a force value very strong (around 2N) compared to the experimental value (around 0.1mN)
Can someone let me know if i correctly use the force calculation feature?
Thanks in advance.
Stéphane.
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At least i would like to know if mesh and the use of Force calculation are correct for this application.
Thank you in advance.
Stéphane.
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I would like to have a look into your model but I cannot open it with the 4.1 and 4.2 versions. I don't have 4.0 because it is said to be pretty buggy.
Cheers
Edgar
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Thank you for your answer, it's a good information so i'll look if i can upgrade to 4.1 or 4.2 version.
Thank you again
Stéphane.
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Hi
Thank you for your answer, it's a good information so i'll look if i can upgrade to 4.1 or 4.2 version.
Thank you again
Stéphane.
Hi Stephane, did you solve your problem? I was able to simulate your file in 4.2 version on Mac, but also there was the result a huge number of 2.4 N. In the plot however the value of 13 mN was listed, different from the value in the table. Anyway, it is far away from your 0.1 mN measurement.
Let me know if you could solve this. I am also interested in diamagnetic simulation.
Wim.