Stackable Ugrinsky Vertical Wind Turbine VAWT

This VAWT uses a design, developed by K.A.Ugrinsky in 1946. It is basically a Miller rotor with integrated Lenz 2 features.

The diameter of the disc is 205 mm. The active rotor diameter is 200 mm.
The rotor shape is taken from Ugrinsky's sketch (see screenshot in files), using dimension R=100.

You can either print the bottom part only once and use the cover, or you can alternatively print the bottom several times and stack them (twisted by 90 degrees), using the cover only on the uppermost part. I am using 2 bottoms and the thing spins nicely in my garden at pretty low winds. If you print both, this one and also the C-Rotor in my other design, you can directly benchmark the two designs.

I glued all parts together with semi liquid cyan acrylate glue.

It is designed for use with 608 ball bearings ( 8mm rod, 22 mm outer diameter, 7 mm high). I am only using 2 bearings and do not install one in the middle to prevent mechanical stress. The bearing covers are protecting the bear