Discussion Forum

Hello!
You can add an extra Ampere's Law in your MF or MEF model, select your magnet domain, switch the Magnetic field to Remanent flux or Magnetization and put in a value.
This will produce a Permanent magnet.
Ralf

Hey Ralf...

Plz let us know that And if i want to implement halbach for 7 pieces of 16 x 4 mm, how can i assign field lines into and out of the paper?
And let us confirm that while applying amperes law, I should divide 16 x 4 into two pieces and assign each piece say 5000 A/m in magnetization in x and y? Kindly confirm that. And also that how can I assign flux lines into and out of the paper (I mean by that field lines from top to bottom and bottom to top assigning)...
And what material should i assign? Iron or material like NdFeb etc???

Plz let me know that, it will be ur great favour...
Regards...

Hello!
You can use my example for a Halbach array; this is in 2D.
So I don't know, what do you mean with "flux lines in and out of the paper"...
In 2D this is not possible.
Ralf

Hy Ralf, immense thanx for ur responce.

The figure is in accordance to my requirement but I cant open the comsol file because of later version.
Wish I could open it.
Let me know please that for NdFeB permanent magnet what should I use in Ampere's Law?

1) Remenant Flux Density
2) BH Curve
3) Magnetization
4) Relative Permeabilty

And on which basis I should use values to the recommended above way by u? Should I assign material as NdFeB or simply use iron? And kindly give me ur email.

Regards...

Hello!
My version is 4.3b, as you marked above...
I use remanent flux density; rotating direction from piece to piece:
first piece: +1.2T in y direction, second piece: +1.2T in x direction, third piece: -1.2T in y direction and fourth piece: -1.2T in x direction and so on...
Other properties are sigma=1S/m and epsilon_r=1.
Ralf

Thanx a lot Ralf...

I have attached the image below, I assigned remenant flux in accordance to ur instructions.

And let me know last few queries, these might be basic but new for me, so plz let me know that is there something like geometry dependency like I should Flux for circular or curved shape geometries and for straight or rectangular parts, I should use AIR medium and what should be the value of Tesla?
And is cube or cylinder formation is necessary around geometry/magnets to check magnetic field with its medium as air?
And last thing plz that I want to know is that I have fixed the base of a beam and want to check the displacement at a Force with frequency of 50 Hz. Plz mention just brief steps.

Regards and thanx in advance.

Hi!
I think the best would be to study comsol manual and some of the examples in the model gallery:
www.comsol.de/models/acdc-module
There you should find some more explanations for basics.
Ralf