Quote:
Originally Posted by sendler
Although, it looks like even a fat foil such as 0040 will measure half max width for a truncation of only 24%.
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I'm working on a table for symmetrical wing sections from Hoerner's book.
The table he has illustrates the drag curve for the wing section as a function of the truncation percentage of chord length.
Also,the mathematical formula is provided for calculating the drag for any % truncation.It requires an entry-level scientific calculator which can handle cube-roots and Y-to-the-x power.A few memory caches are handy.
It will be next Saturday at the soonest before I'll have it ready to scan/Photo-Bucket/and transfer over.
I think you'll like it.
Hoerner says it can be used for any conventional wing as long as the maximum thickness is located around 30% of chord.The math is based on the section thickness only.It doesn't matter what the thickness ratio is.
You are going to be alarmed at how quickly the drag rises as you chop away the trailing end.
Overall,the aft-body of the wing is responsible for over a 900% (9-X) drag reduction of the wing.
And also,the Kamm chop does not work with wings as it does with bodies of revolution or half-bodies.I'm working on a table for that as well.But I would advise you to wait before you lock in any design until you see this material.
If you can find access to the book,'Aerodynamiks des Fraftfahrzeugs' by Baron Reinhard von Koenig-Fachsenfeld,1951,you'll have access to a gold mine of data.Also 'Aerodynamic Drag' by Sighard Hoerner.