UgrinskyCrossSection03.3dm is a Left Handed helix spiral.
Turbine deflects wind downward? Lift force occurs? Less efficient than RH?

Could mirror cross section?
Instead, will redo as RH spiral.

- Brian

This is really interesting Brian,

Thank you

James Elliott

The cross section has similarities to the famous yin-yang symbol!

Thanks for sharing this Interesting info!

The .step models at mcmaster quickly open in MoI, and can be saved as .3dm files.
I plan to use one of these bold models to boolean difference a solid block model, to make internal threads.

https://www.mcmaster.com/screws/system-of-measurement~metric/metric-18-8-stainless-steel-button-head-hex-drive-screws/

Also, there is a more efficient radius setting for the rotor.
The smaller radius blade diameter is 0.35 * Diameter of rotor.
The larger radius blade radius is still = L = 1.0 * R = 1.0 * D/2. Depending on the ratio of rotor tip speed to incident wind speed, the 1.0 factor could be 1.3.
So I am re-doing the model...

https://www.witpress.com/Secure/elibrary/papers/ESUS21/ESUS21011FU1.pdf
This paper was with non-spiral rotor.
I have not seen any data for a helical rotor.

- Brian

Some notes on Helical Wind Turbines, this might provide some useful input to the discussion:
https://windcycle.energy/helical-wind-turbine/
best regards
O.

Thank you for the link, Ken.
- Brian