On Sep 5, 12:02*pm, Leviterande Leviterande.
wrote:
'a[_3_ Wrote:



;659074']On Sep 5, 1:10 am, Leviterande Leviterande.
wrote:-
Hi all!
Volf propeller hehttp://www.rexresearch.com/volfprop/volfprop.htm

I have been thinking alot about how this propeller would do, I wish I
had a workshop, CNC, and tools to build one.. this amazing prop is
claimed to be *super quiet and efficient.. so any more info from the
article on it or any *word of experience in propellers are very
appreciated

what about this propeller
( hit CTRl-F *and type "An Air Screw That Ridicules Propeller"
)http://www.rexresearch.com/aero/1aero.htm

regards
kalle

--
Leviterande-

That's a very old patent! If you think about a propeller for low speed
flight, think about it as a rotating wing. You'll notice high
perfornance gliders have long slender wings, and the best props look a
lot like that, with an additional twist. Ducting helps, as do Q tips
on propeller edges, but I did read somewhere you gain as much
efficiency by increasing the propeller diameter as the q tip length.
Makes me wonder if the vortex decreasing terminations on wings might
be as well used just by increasing the wingspan by that amount.

so *your guess is that none of the props are more efficient then todays
propellers? the todays propellers didnt differ *from the ones used 100
years ago btw...

Kalle

--
Leviterande

Oh? Constant speed props are that old? On a more serious note, today's
props are part of an aerodynamic systems and better engineered. Would
you care to cite a reference supporting your claim tha efficiencies
have not improved? Other than one you write yourself, of course.