Menu

Discussion Forum

New Discussion
Filter

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.

Wrong pole directions give "accurate" results in permanent magnet model

Posted Mar 2, 2021, 9:38 p.m. EST Electromagnetics, Low-Frequency Electromagnetics, Studies & Solvers 1 Reply

Mohamad A
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

I'm modelling a simple permanent magnet with north and south pole.

The problem I'm having is using the remanent flux density, the magnetic field I've initialized has both north and south pole in the same direction, yet the solution given of the magnetic flux density is fairly concordant with what I'm getting in a hall probe.

Intuitively, this would be clearly wrong as the streamline/arrow surface are assymetrical and don't resemble the field lines that you'd typically see in a permanent magnet. However, with opposite directions, the solution does not resemble the values of the hall probe at all.

I'm hoping that someone who is more experienced in magnets would shed some light on this, and let me know if the results of my model are purely coincidental or if there is something else to it.

Thanks

Attachments:

1 Reply Last Post Mar 3, 2021, 10:29 a.m. EST
Robert Koslover Certified Consultant
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 3 years ago Mar 3, 2021, 10:29 a.m. EST
Updated: 3 years ago Mar 3, 2021, 10:31 a.m. EST

First, the remanent flux density in an ideal bar magnet should be all in one direction. You should be specifying the direction of the flux density, not poles per se. Second, the blocks you have labeled "north" and "south" and which you have stacked along the z-direction, are (unexpectedly) magnetized in the x-direction! See image attached. I suspect you intended to magnetize the structure in the z direction, right? If so, that's your problem.

-------------------
Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
First, the remanent flux density in an ideal bar magnet should be all in one direction. You should be specifying the direction of the flux density, not poles per se. Second, the blocks you have *labeled* "north" and "south" and which you have stacked along the z-direction, are (unexpectedly) magnetized in the x-direction! See image attached. I suspect you intended to magnetize the structure in the z direction, right? If so, that's your problem.

Attachments:

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.

Suggested Content