more efficient props

[Dorkhedeos]

i was just thinking, if a shroud on a radiator fan makes it work better, then how come nobody uses a shroud on a boat prop? wouldnt it make it more efficient since it would concentrate the stream of water in one area

 

[AWaddle322]

i was just thinking, if a shroud on a radiator fan makes it work better, then how come nobody uses a shroud on a boat prop? wouldnt it make it more efficient since it would concentrate the stream of water in one area

A fan moves air, a prop moves water. No it will not help. The hydronamic drag will be greater than any gains that you could gain. The rusult would be a prop be less efficient bacause of prop slip. Mercury atually did this in some outboards to protect the prop from shallow bottom lakes. it caused alot more prop slip.

Allen