Torque between two cylindrical magnets
Torque between two cylindrical magnets
(OP)
Hi,
I am new in this forum, I hope somebody can help me to answer my question.
It seems like a simple problem.
I have 2 cylindrical magnet which have opposite magnetic direction,one is placed in the top of the other (with small gap).
I have tried to use a FEA-based software (Maxwell) to simulate the problem, I got a reasonable result of repulsive force between these 2 magnets. But the problem is that I got a significant value of torque between these 2 magnet.
I was thinking that the torque produced should be 0.
Is there any idea about this result?
I am new in this forum, I hope somebody can help me to answer my question.
It seems like a simple problem.
I have 2 cylindrical magnet which have opposite magnetic direction,one is placed in the top of the other (with small gap).
I have tried to use a FEA-based software (Maxwell) to simulate the problem, I got a reasonable result of repulsive force between these 2 magnets. But the problem is that I got a significant value of torque between these 2 magnet.
I was thinking that the torque produced should be 0.
Is there any idea about this result?





RE: Torque between two cylindrical magnets
RE: Torque between two cylindrical magnets
Thank you for your answer,
I agree with you about non-uniform magnetic field distribution.
But since I got this result from a simulation, I assumed that the magnetic field produced by each magnet would be identical (if not depend on the mesh).
Do you think we have analytical method to calculate torque/force for a simple cylindrical/bar magnet?
Thank you in advance.
RE: Torque between two cylindrical magnets
I would suggest to re-run the simulation with finer mesh density (especially in the gap and the highest-flux areas) to see if the computed torque decreases. If it decreases, then try it again with even smaller mesh density....keep reducing mesh density until computed torque no longer decreases... I suspect the computed torque would be very small at that point.
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(2B)+(2B)' ?
RE: Torque between two cylindrical magnets
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(2B)+(2B)' ?
RE: Torque between two cylindrical magnets
Since your geometry is rotationally symmetric, you'll have a simpler time if you model in 2D.
RE: Torque between two cylindrical magnets
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(2B)+(2B)' ?
RE: Torque between two cylindrical magnets
In the first model, I have already placed my model to the center of simulation domain.
Based on the suggestions, I tried to refine the mesh and re-run the simulation, -> the torque decreased up to micro Nm for a model size 80mm in D and 2mmm gap!!
Probably I will make a 2D model and see the differences.
Thank you.