Electromagnet strength

dimanche 1 décembre 2013

Hello,

If we have an electromagnet

with some lifting force, for example 10N, and make core area smaller at the ends, to concentrate the magnetic field (without saturating the core)

according to the formula, for magnetic flux

magnetic field density B , will be greater.

For example if we make area, 4 times smaller we will get 4 times greater B

Then electromagnet force will increase too, and become 4 time greater

So we get more force, without puting in additional energy.

But I have made a magnetic field simulation in FEMM

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

and there is an increase in B, but much smaller than this according to the formula.

Is there something wrong with the simulation, or my thoughts are wrong...?

http://en.wikipedia.org/wiki/Magnetic_flux

http://en.wikipedia.org/wiki/Electromagnet