Learning Forum

[cunyi.ji]

Hello,



After exporting in RMxprt a 3D motor model with the 1/4 symmetry to Maxwell 3D: how are volumetric results affected, such as ohmic loss or core loss? Is it calculated for only 1/4 of the 3D model and then multiplied by 4, or is it just calculated for 1/4 of the 3D model?

In Icepak you can adjust EM losses to obtain the temperature distribution, so should I use the 1/4 3D model in Icepak too? Of course, this would depend does the symmetry affect to volumetric results in Maxwell 3D.

Also, how do I get full 3D model with RMxprt, when I use "fractions 1" in design settings, I get the complete motor radially, but axially is halved.



Additionally, when I port both the 2D and 3D models of the motor, the results are extremely different between 2D and 3D. I know that there should be differences, but I think it is too high. The B field in 2D is maximum 1.6T, while in in 3D it is 4T. The torque, currents, induced voltages, etc are considerably different (forms and values).

Regards,

[MirandaH]

The calculated result in Maxwell will be the full model considerring symmetry multiplier

[cunyi.ji]

In Icepak simulations, when assigning the EM Losses, should I use the complete model or the 1/4 one?

[MirandaH]

You can use either, Icepak is using element based mapping from Maxwell. Full model from Maxwell to Icepak, or partial model from Maxwell to Icepak with symmetric boundary.

[cunyi.ji]

In Maxwell 3D there is symmetry boundary, but in Icepak there are no boundaries options like Maxwell 3D.

In case I'm using the 1/4 model, should I just copy-paste it from Maxwell 3D to Icepak without assigning symmetry boundaries?

[MirandaH]

You will need to assign symmetric boundaries in Icepak as well.

[cunyi.ji]

In Icepak, as you see in the image, there are no boundaries option in project manager, how do you set symmetric boundaries?

[MirandaH]

"Fractions 1" should give you the full model, I would suggest to reinstall Ansys Electronics Desktop and update to the newest version 2025R1.

[cunyi.ji]

It gives the full model but radially, axially is cut in half. Should fractions 1 also give full model axially?

My school only has the 2023 license version.

[MirandaH]

Yes, it should give full geometry.

[MirandaH]

For 2D and 3D, there are expected difference but not as high, are you comparing 2D and 3D partial model from RMxprt? Does it include the external circuit? How are the mesh looks like for both models?

[cunyi.ji]

Yes, both from RMxprt, both includes the external circuit auto-generated by RMxprt. Mesh options aren't modified, since it takes a lot to solve transient simulations. I guess that the poor mesh is causing B field concentrations in 3D?

[MirandaH]

Yes, mesh will affect calculation accuracy.

[Rabindra Paul]

Symmetry boundary option in AEDT Icepak is available for wall. User may select the appropriate face, assign thermal -->wall-->symmetry wall

 

 

[cunyi.ji]

When I applied wall symmetry I got the following error:



I also tried using the finest mesh settings, but still the same error.



The two symmetry planes are auto-generated by RMxprt. I also tried manually creating the symmetry planes, but still same error.

What is causing this? I don't think it is the mesh, because without the wall symmetries the simulation runs just fine.

[Rabindra Paul]

Hi - Thanks for the comment. Please contact Icepak support through customer portal. The symmetry must satisfy wall bc requirement which should be at the domain boundary. We need to review the model to find out the exact cause.