SailNet Community - View Single Post - sailors and wind farms
View Single Post
post #26 of Old 11-23-2007 Thread Starter
overdue at Sans Souci
Diva27's Avatar
Join Date: Nov 2007
Location: Midland Ontario
Posts: 167
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 10
Originally Posted by Giulietta View Post
That's not the reason the blades are twisted.

They are twisted to ensure that lift at the tip is equal to lift at the root.

This is achived by twisting as you say, thus reducing angle of attack and aspect ratio, guaranteeing that lift os proportaional and the same along the lenght of the blade.

If this was not so, the blade would colapse and fold, due to the greater lift present at the tips.
Much thanks for the explain. But I did think apparent wind was also at play. In multielement wing sails for C-cats, they introduce twist in the top to prevent stallage that would otherwise occur. Apparent wind is higher at the top of the mast (as in all sails) and from a different direction because of wind gradient.But with rotating blades maybe this is less important than the lift loading issues.
Always learnin.'

C&C 27 Mk 1
Midland Bay Sailing Club

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

It is better to be vaguely correct than specifically wrong.
Diva27 is offline  
Quote Share with Facebook
For the best viewing experience please update your browser to Google Chrome