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Inaccurate force calculation

Posted Jun 12, 2022, 10:31 p.m. EDT Electromagnetics, Plasma Physics, Physics Interfaces Version 6.0 2 Replies

希圣 鲁
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Hello everyone, I am trying to use the current module and the magnetic field module to couple, and then calculate the force in a certain domain through the force calculation in the magnetic field. At present, it is found that the calculated force is much smaller than the formula derivation. What may be the reason?

2 Replies Last Post Jun 26, 2022, 8:32 a.m. EDT
Mark Harradine
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Posted: 3 years ago Jun 14, 2022, 2:42 a.m. EDT

If you are using the Maxwell Stress tensor to cacluate force, this is very mesh dependant and you will need to ensure the boundaries on the domain for which you wish to calculate the force have a sufficiently fine mesh, (possibly using boundary elements). Also, sharp corners can cause inaccuracies, consider filleting any sharp edges in the calculation domain. Also, if you are using symmetry in your model, you will need to multiply the calculate force by 2/4/8 depending on the symmetry you have used in the model.

Mark

If you are using the Maxwell Stress tensor to cacluate force, this is very mesh dependant and you will need to ensure the boundaries on the domain for which you wish to calculate the force have a sufficiently fine mesh, (possibly using boundary elements). Also, sharp corners can cause inaccuracies, consider filleting any sharp edges in the calculation domain. Also, if you are using symmetry in your model, you will need to multiply the calculate force by 2/4/8 depending on the symmetry you have used in the model. Mark
希圣 鲁
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Posted: 3 years ago Jun 26, 2022, 8:32 a.m. EDT

If you are using the Maxwell Stress tensor to cacluate force, this is very mesh dependant and you will need to ensure the boundaries on the domain for which you wish to calculate the force have a sufficiently fine mesh, (possibly using boundary elements). Also, sharp corners can cause inaccuracies, consider filleting any sharp edges in the calculation domain. Also, if you are using symmetry in your model, you will need to multiply the calculate force by 2/4/8 depending on the symmetry you have used in the model.

Mark Thank you for your answer, I think the calculation may be inaccurate due to the coupling through the surface current density in the magnetic field

>If you are using the Maxwell Stress tensor to cacluate force, this is very mesh dependant and you will need to ensure the boundaries on the domain for which you wish to calculate the force have a sufficiently fine mesh, (possibly using boundary elements). >Also, sharp corners can cause inaccuracies, consider filleting any sharp edges in the calculation domain. >Also, if you are using symmetry in your model, you will need to multiply the calculate force by 2/4/8 depending on the symmetry you have used in the model. > >Mark Thank you for your answer, I think the calculation may be inaccurate due to the coupling through the surface current density in the magnetic field

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