Propellor design

[Wansworth]

 

[ChromeDome]

Not completely different to the Sharrow, discussed here prevoiusly

 

[fisherman]

Towing vessels often use a Kort nozzle, which has to be fitted to the hull independent of the prop. I wonder if a simple ring on the ends of the propeller blades would have the desired effect, cheap and simple I would have thought. It does, however increase the wetted surface area that is rotating. Some one must have tried it.

Someone did RingProp