3D Nonlinear Static Magnetic 1

[Tininmartinez]

Hi!! I am improving a big 3D model of a guitar pickup with string, and as u know, AlnicoV is modelated by a B-H graph and a coercive force. Once I have finish the program, and I want to solve it, I put eqsl,iccg ... ok, all make sense. But it is curious, cause if I put permeability (in the x axis) for AlnicoV (strange because is a nonlinear material), i get the solution; else not (there is an unconvergence). Does anyone know why?? Do you know a way to solve nonlinear static 3D Models?? Thanks.

 

[hacksaw]

you need finite mu in order for iterative scheme to work. There are books, research journals, web-sites and codes that deal with those methods.

 

[Tininmartinez]

Thanks Hacksaw, I know that i need the linear permeability, but as you know, in a 3D model, if you have a permanent magnet (modelated by a B-H Graph and a coercive force in Z axis, for example), the B-H graph will only be used in the points where the permeability has a value of 0 (In the Ansys manual tells that is not needed to introduce a value for a nonlinear model). Ok, I use an anisotropic magnet; if you put MURX=0, then there is a incorvengence, but if i try MURZ=MURY=1 and MURX=0, the i get solution (but if MURZ=0, the solution in which i am interested, cause my coercive force is in this axis direction, the solution unconverge, too). I have been looking and looking for this websites and information for my nonlinear 3D Static Magnetic model, but i can´t find it, and I only want to..... SOLVE THE MODEL !!!!!!! Anyway, thanks people

 

[hacksaw]

the relative permeability of free space is unity.

sounds like you need to contact the ansys folks; you should not have to rely on the MURX/Y/Z as a switch for the B-H characteristic.

 

[Tininmartinez]

Jeje, I have met Ansys Folk, but they gave me "incorrect" commands, cause i am working for a private investigation in a German University and they support us. Anyway, there are some "software errors" in Ansys... we found some of them in the Emag. Thanks, i will continue trying to SOLVE the program. Chao

 

[wijono]

I got the similar problem with mu-r. The conclusion are:
- The BH curve must has the mu-r equal or greater 1
- Do not fill the mu-r with 0, just leave blank