Finding airgap flux from a permanent magnet

AI Thread Summary
The discussion centers on calculating the magneto-motive force (MMF) of a permanent magnet, with confusion surrounding the use of material tables that provide coercive field strength (Hc) in kA/m. The formula MMF = Hc * length * area is questioned for its applicability in determining flux using the equation Flux = ugap * MMF. The ultimate goal is to find the flux in a magnetic circuit with a small air gap driven by a permanent magnet. A suggestion is made to explore a free student version of a finite element analysis (FEA) program for further experimentation. The conversation highlights the need for clearer resources and tutorials on this topic.
nickw1881
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The problem I am having is that I cannot seem to find the magneto-motive force of a permanent magnet. Most material tables give a Hc in kA/m, which I take to mean I multiply by the length of the magnet, then by the area of the magnet to get my total magneto-motive force.

So does MMF=Hc*length*area? Can I use this formula in Flux=ugap*MMF?

My ultimate goal is to find the flux in a magnetic circuit (driven by a permanent magnet) with a small air gap. If there is a tutorial someone could point me to I would be grateful. Google only returns a bunch of stuff on high tech magnet research and some pay-per-view FEA demonstration papers.
 
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Nick,

I'm not sure how to answer your question because I'm learning this, too. But there's a FEA program you can get a free student version of to tinker with. Check out this:

http://www.quickfield.com/free_soft.htm
 

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