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Old 11-08-16 | 01:51 AM
  #44  
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79pmooney
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Originally Posted by jfowler85
Correction:


Air resistance is proportional to the negative half of the drag coefficient, cross sectional area, and air density, and grows exponentially with velocity squared.
From "Theory of Wing Sections" by Abbot and von Doenhoff:

Drag = 1/2 roe V^2 S Cd where roe = the mass density of air, V= velocity, S = Area (wing area for this treatise), Cd = coefficient of drag

Drag (sir resistance) grows with velocity squared and is proportional to area, air density and coefficient of drag, ie the drag characteristics of that shape.

I'm just a dumb engineer trained in fluid mechanics. I have never heard of the 'negative half of" anything, nor that air resistance grows exponentially with velocity. Maybe I was asleep (for six years) or perhaps my professors were not the best. Granted, the reference I gave, although once considered the bible on wing sections and the reference from which many airplanes were designed (and flew), was published in 1949 and probably quite wrong by now.

Ben
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