Shaded pole motor magnetic field simulation in FEMM

For a long time I wanted to simulate the electric and magnetic quantities in a shaded pole motor and last week I finally found 10 minutes to dedicate to this activity. I find these motors fascinating for their simplicity and for how they work by using the laws of electromagnetism.

Shaded pole motors are a variety of induction motors. They are quite the cheap type of motors: you can usually find them in old washing machines (powering the water pump for example) or even in new white goods where they may be used for periodic (but not frequent) tasks, for instance every 30s for turning a wheel. It is extremely rare to find a shaded pole motor that runs continuously. In the picture below (from Wikipedia) you can find an example of such motors.