Toroidal Rotor - parametrized

I saw a video about this concept of making rotors that shall be relatively quiet. I have a quite cheap fan (20cm) and made a new rotor for it.

You can change anything form the number of blades to the diameter of the axis etc. The stl file is generated using the default values in the scad-file. The pictures are from exactly those parameters, which fit my fan motor.

Update 02/14: Better description of the parameters, renamed some for better understanding.