Magnetic Fields: Measuring Magnetic Field in a Point Inside a Volume

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To measure the magnetic field at a specific point inside a volume influenced by multiple magnetic sources, one can use measurements taken at a point on the surface of the volume. Understanding the magnetic field of a single permanent magnet is crucial, as the total field can be derived by summing the fields of individual magnets. An approximation treats a permanent magnet as a solenoid, which simplifies calculations by using parameters like reluctance and equivalent current. However, accurately computing the force between two permanent magnets remains challenging, often requiring finite element analysis rather than direct computation. This highlights the complexities involved in magnetic field measurements and calculations.
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I have a cluster of magnetic sources around a volume and I need to know the real magnetic field in a point (namely x_0) inside the volume by measurements in another point x' in the surface of the volume.
I'm getting mad
 
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hehe,

I'm getting mad about computing the magnetic field of only 1 permanent magnet.
I guess that basically, if you know the field of 1, you will know the total field (summing).
Here is a wikipedia link, in which an approximation is made, to consider 1 magnet as a solenoid. http://fr.wikipedia.org/wiki/Réluctance
Unfortunately i did not find any equivalent in English.

It says :
A permanent magnet with remnant field B, length l, section s, \mu its permability, it is equivalenent to a soleoind :
- of reluctance R = l/(\mus)
- with : N.I = (l.B)/\mu, N the equivalent number of current loops, I the equivalent current
- length l and section s.

Imagine how is it frustrating when you need to analytically compute the force between two permanent magnets (actually, there is no viable direct computations, only based on finite element decompositions).

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Correct me if I'm wrong.
http://ghazi.bousselmi.googlepages.c...3%A9sentation2
 
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