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Freely moving body due to magnetic field forces

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Hi,

I am trying to set up a 2D model in which the inner circle of permanent magnets (domains 7,8,9,10 - see attached picture) is moving in reaction to the magnetic field interraction with outer circle of permanent magnets (domains 3,4,5,6 - see attached picture). The outer ring is rotating along the center of the system, while the inner circle should be free to move (translation plus rotation). The inner circle and the outer ring are creating the first identity pair, while the outer circle and the outside domains (domains 1,2) - the second pair.

I am using the Magnetic Fields, no currents physics for calculating magnetic forces along with Global ODEs and DAEs for solving the translations and rotations of the inner magnets due to forces and torque.

I am not certain which approach should I use to solve the problem of moving the domains.

One option would be to take the translations and rotations into account in the geometry section and use auto remeshing in the Time Dependent Solver. I am wondering is there a way to automatically remesh only one domain every step of the simulation? There is only one domain which needs to be remeshed - the thin gap between the outer ring and the inner circle (domain 11) and such option would significantly reduce the time of each step calculation.

Another approach could use Rotating Machinery, Magnetic module along with Moving Mesh module. I would use The Rotating Machinery for rotations of the assembly parts and the Moving Mesh for translation of the freely moved inner circle. This approach would eliminate autoremeshing, however it might lead to inverting mesh elements and their poor quality due to the very fine mesh that is needed in such simulation.

I would like to ask you is the second approach a viable option? And if so is it then scalable for a 3D model? Or should I just stick to the easiest but more time consuming method? Or maybe there is another way to solve the problem?

I would really appreciate your help.


1 Reply Last Post Oct 21, 2015, 2:20 p.m. EDT
Johan Nicolai Fjellanger

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Posted: 9 years ago Oct 21, 2015, 2:20 p.m. EDT
I'll up this question, as I am wondering much of the same.
I'll up this question, as I am wondering much of the same.

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