Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Help with meshing a simple solenoid, to be able to calculate its inductance

Please login with a confirmed email address before reporting spam

Good afternoon,

I have a parasolid file of a solenoid, and am trying to calculate its inductance using the mef package. The mph and parasolid CAD files are attached, as well as a screenshot of the geometry.

https://i.imgur.com/JTrkJ5O.png

I have been trying to follow the spiral inductor example:

www.comsol.com/model/download/629391/models.acdc.spiral_inductor.pdf

but am having trouble meshing this geometry. I thought best would be to use triangular mesh on the face, and then use a swept mesh along the coil itself. Then use a free tetrahedral mesh for the "air box". Could someone help with meshing, and then ultimately obtain the inductance of this coil?

Many thanks in advance,



2 Replies Last Post 2020年2月18日 GMT-5 20:40

Please login with a confirmed email address before reporting spam

Posted: 5 years ago 2020年2月18日 GMT-5 10:08
Updated: 5 years ago 2020年2月18日 GMT-5 10:08

I have a couple suggestions:

1) there is a blog post here that should help with meshing of a coil: https://www.comsol.com/blogs/improving-your-meshing-with-partitioning/

2) I tried to mesh just the coil part and it took a long time. Something might be wrong with the predrawn file. I would suggest to draw this native in comsol. There is a helix function so you should be able to mimic what is wanted.

3) I would suggest you make the air box a little bigger . You will also need at least one coaxial port at one end of the inductor. This you can do with a workplane. You can use two coax ports if you want as you can translate between s-parameters and ABCD parameters to get a series impedance.

I have a couple suggestions: 1) there is a blog post here that should help with meshing of a coil: https://www.comsol.com/blogs/improving-your-meshing-with-partitioning/ 2) I tried to mesh just the coil part and it took a long time. Something might be wrong with the predrawn file. I would suggest to draw this native in comsol. There is a helix function so you should be able to mimic what is wanted. 3) I would suggest you make the air box a little bigger . You will also need at least one coaxial port at one end of the inductor. This you can do with a workplane. You can use two coax ports if you want as you can translate between s-parameters and ABCD parameters to get a series impedance.

Robert Koslover Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 5 years ago 2020年2月18日 GMT-5 20:40

Based on the figure you posted, that's an awfully large number of turns of closely-spaced fine wire. I'm not surprised you would have trouble meshing that wire with sufficient detail, within that volume. Anyway, you might want to step back a little and try modeling a similar geometry with fewer turns of more widely-spaced and thicker wire first, just to ensure that you can actually do it, and then compare your model results to the expressions that people used to use before they were blessed with such powerful computers and software! Specifically, the following references, among others, may also be of some interest to you: https://nvlpubs.nist.gov/nistpubs/bulletin/04/nbsbulletinv4n3p369_A2b.pdf https://nvlpubs.nist.gov/nistpubs/bulletin/08/nbsbulletinv8n1p1_A2b.pdf https://www.bookdepository.com/Inductance-Calculations-Frederick-W-Grover/9780486474403 Good luck.

-------------------
Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
Based on the figure you posted, that's an awfully large number of turns of closely-spaced fine wire. I'm not surprised you would have trouble meshing that wire with sufficient detail, within that volume. Anyway, you might want to step back a little and try modeling a similar geometry with fewer turns of more widely-spaced and thicker wire first, just to ensure that you can actually do it, and then compare your model results to the expressions that people used to use before they were blessed with such powerful computers and software! Specifically, the following references, among others, may also be of some interest to you: https://nvlpubs.nist.gov/nistpubs/bulletin/04/nbsbulletinv4n3p369_A2b.pdf https://nvlpubs.nist.gov/nistpubs/bulletin/08/nbsbulletinv8n1p1_A2b.pdf https://www.bookdepository.com/Inductance-Calculations-Frederick-W-Grover/9780486474403 Good luck.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.