Where does maximum flux density occur in a well-designed electric machine?

In a well-designed electric machine, the maximum flux density typically occurs in the air gap between the stator and rotor for most machine designs, like in induction motors or synchronous machines. This is because the air gap represents the point of highest magnetic reluctance compared to the other machine parts which are usually made of materials with higher magnetic permeability. Thus, to maintain the required magnetic flux with the least amount of magnetomotive force (MMF), the air gap is minimized to the extent possible within mechanical constraints. Additionally, high flux density locations can also be found in the teeth of the stator and rotor, due to the concentration of magnetic flux in these narrow areas.