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Eddy currents in a copper plate in a time dependent 3D model

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Hello,

I wish to calculate the eddy current loss in a circular copper plate. The eddy currents in the plate are generated due to time varying field in a copper coil above the plate.

The copper coil is excited with 1A/s from 0 to 100 s. So, the current in the coil changes from 0 to 100 A in 100 s. I have specified the external current density in the copper coil and the default magnetic insulation condition is applied at the outer air box.

When I run the simulation, the convergence plot is triangular. Additionally, NLfail increments continuously. Even after 5 hours, the progress is still less than 20 %.

Can you please let me know where I am going wrong? The mph file (v5.5) is attached herewith. Any help in this regard is highly appreciated.

Thanks a lot.

Warm Regards, Pranoti Raut



3 Replies Last Post 2021年10月8日 GMT-4 10:25
Robert Koslover Certified Consultant

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Posted: 3 years ago 2021年10月6日 GMT-4 23:18
Updated: 3 years ago 2021年10月6日 GMT-4 23:23

Well, I think there are a number of separate issues with your model configuration, but in regard to your convergence issue, consider fixing the gauge. See screen image attached. This should at least make all your NLFails go away (although the simulation still begins rather badly). I think you should make some other changes too, but I'll let the real experts for these kinds of models provide those suggestions. Good luck.

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Scientific Applications & Research Associates (SARA) Inc.
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Well, I think there are a number of separate issues with your model configuration, but in regard to your convergence issue, consider fixing the gauge. See screen image attached. This should at least make all your NLFails go away (although the simulation still begins rather badly). I think you should make some other changes too, but I'll let the real experts for these kinds of models provide those suggestions. Good luck.


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Posted: 3 years ago 2021年10月7日 GMT-4 07:21
Updated: 3 years ago 2021年10月8日 GMT-4 10:22

Dear Mr. Koslover,

I added the gauge fix as you suggested and it improved the convergence and computation time of my model. I also scaled the A variable manually by 0.001. This has solved my problem.

Thanks a lot for your time and suggestion.

Edit: I have a doubt regarding the current flow in the plate. The image is attached herewith. Shouldn't the current be going sideways along the length of the slit and resume its circular path?

Please state if there are any other discrepancies in the model.

Thank you.

Warm Regards,

Dear Mr. Koslover, I added the gauge fix as you suggested and it improved the convergence and computation time of my model. I also scaled the A variable manually by 0.001. This has solved my problem. Thanks a lot for your time and suggestion. Edit: I have a doubt regarding the current flow in the plate. The image is attached herewith. Shouldn't the current be going sideways along the length of the slit and resume its circular path? Please state if there are any other discrepancies in the model. Thank you. Warm Regards,


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Posted: 3 years ago 2021年10月8日 GMT-4 10:25

Hello,

I have a doubt regarding the current flow in the plate. The image is attached herewith. Shouldn't the current be going sideways along the length of the slit and resume its circular path?

Please let me know if there are any other discrepancies in the model.

Thank you.

Warm Regards,

Hello, I have a doubt regarding the current flow in the plate. The image is attached herewith. Shouldn't the current be going sideways along the length of the slit and resume its circular path? Please let me know if there are any other discrepancies in the model. Thank you. Warm Regards,

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