Wing design is very complex. Folks make careers out of doing it.
I hadn't noticed ;-)
I'd suggest getting a copy of a spreadsheet written by John Hazel called something like Liftroll. It's a good way to play with the basic aspects and make reasonable choices of span, twist and chord. The basic principles are consistent local Cl's across the span with an elliptical distribution of lift across the span to minimize induced drag.
I've played with LiftRoll, but a couple of things escape me....
I can adjust the planform twist to get eliptical lift distribution at one AOA
It is then off at a different AOA. (as expected for a rectangular platform)
So how do I convert this non-eliptical lift distribution to a drag number for comparison.
I can use LiftRoll to adjust twist to make it look like an elipse or not, but how do I
generate the comparison number from my origional post, IE wing 1 will have min sink of 1 fps
and wing 2 will have minimum sink of X fps?
Paul
In General: Min sink is when (Cl ^(2/3) /Cd) is maximized.
How do I use LiftRoll to get a wing Cd, Cl given a polar Cl, Cd?
In LiftRoll is av/mx Cl the Cl I want to optimize for? How do I go about guessing an AOA? (Again from the airfoil polar? )
If you can't find John's spreadsheet, I can forward either the simpler earlier version or a more involved later version. If I can figure out how, I could just put it on my website.
Bill Swingle Janesville, CA
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