[Paddlewise] The WIngs of Man (and kayaks)

Nick writes:

> There is some good data about the relative efficiency. The wing paddle 
> is apparently about 89% efficient and the "conventional" paddle blade 
> is about 74% efficient. What is still an open question is why the wind 
> paddle is more efficient. 

I wonder how efficiency is defined here. Is it lift to drag ratio? In 
that case I would venture that the answer is the same as for an airfoil 
versus a flat wing- less turbulence and more laminar flow over the paddle.

Of course, like an airfoil, an asymmetric wing paddle operates 
efficiently only in a relatively narrow range of angles of attack. 
Outside of that it will stall. There's always a tradeoff.

-- mike
-----------------------------------
Michael Edelman   medelman_at_ameritech.net
http://www.foldingkayaks.org
http://www.findascope.com



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