Hello,

I'm designing a magnetic device very similar to a speaker circuit (i.e. a bottom and top plate, a central pole, and a ring magnet). The only exception is that I'm adding an  adjustable leakage path on the outside diameter, and inserting a coil in the empty space between the ring magnet and central pole. Also instead of an air gap where the voice coil usually is there will be a somewhat magnetic material.

OK with that said I did a magnetic circuit analysis and then made a spreadsheet so that I could quickly look at the effect of changing variables. After that I used Ansoft's "Maxwell" software to run a 2D (radial) model. The FEA results and my spreadsheet  were in very good agreement. Am  I right to expect that the 2D model in this case is better than a 3D model?

So my other question is how accurate should I expect the model to predict the physical device? Assuming all the B-H curves I used in the analysis accurately reflect the construction materials, and I do indeed construct the device as I modeled it. I've heard that flux densities usually end up being half of what the model predicts.