Beginers Simulation Tool Needed

[johnblack]

I would like to ask for recommendation regarding tool/software application for basic (but correct) simulation of magnetic fields and calculation of magnetic force for experiments with permanent magnets. I downloaded Vizimag 3.18, however this tool is very limited and does not meet my expectations. Please advice. Thank you.

 

[MagMike]

I put together a listing of simulation tools in the FAQ section. All of them will simulate magnetic fields. Accurate calculation of magnetic force is tricky. Previous experience has shown they all tend to over-estimate the forces.

Here is the weblink:

http://www.eng-tips.com/faqs.cfm?fid=1112

Mike

 

[johnblack]

Thanks.

The problem is a calculation of a magnetic force (I need just 2D simulation/calculation)

Does anyone know a correct formula to calculate force between two permanent magnets (same materials, same characteristics) that have different sizes (block magnets: x,y,z) when you know distance between them as well as angle..?

Thanks.

 

[MagMike]

I am not aware of any formula to directly calculate the force between two magnets when there is an air gap.

FEA is usually the preferred method in these instances. If you just need 2D simulation, there are some freeware programs available in that FAQ. Each program will have a learning curve associated with them, but it is usually worth the effort.

Mike

 

[mac2]

Several years ago a paper was presented at the IEEE magnetic society meeting that provided a closed form solution for calculating the force between two permanent magnets. The variables were the x,y,z dimension of each magnet, the off-set and gap if any and the direction of magnetization. The magnets did have to be made of the oriented domain type.

 

[MagMike]

Thanks mac2! I found this article (one needs to be an IEEE member to view the entire article):

http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1063554

johnblack: Are you trying to calculate attractive or repulsion forces between your magnets?

Mike

 

[electricpete]

For 2-d simulation I would heartily recommend FEMM.

http://www.femm.info/wiki/HomePage

Fairly to use interface directly in FEMM

Easy to interface with Matlab to automate tasks such as building geometry and analysing results.

Very active and helpful user forum

http://tech.groups.yahoo.com/group/Femm/

I am not aware of any analytical solution for the general problem of attraction between two magnets. I guess you can solve a bunch of similar problems and try to build a correlation to a simple function for that class of problems (empiracal vs analytical solution). Of course 2d FE solution is also sometimes also a poor approximation of real world problem, depending on the geometry

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