Airfoils
Airfoils
(OP)
I have a question about the nose down pitching moment. When talking about cambered vs. a symmetrical airfoil, do they both produce a nose down pitching moment or just the cambered airfoil?
Thanks
Thanks
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RE: Airfoils
moment is then created by having the CofP away from the 1/4 chord position, so any airfoil "can" have aero. moment.
RE: Airfoils
RE: Airfoils
Trimming the stab (ie changing the AOA) will produce a pitching moment.
RE: Airfoils
RE: Airfoils
a cambered airfoil would produce lift at zero incidence and quite likely moment as well.
RE: Airfoils
Timelord
RE: Airfoils
i was mentally following on from no lift, no moment (ie no anything). in any case, with no lift (no Cl) so no induced drag, but i guess you are left with a little profile drag.
RE: Airfoils
At what main frequency would you expect the airfoil to vibrate under these conditions?
Fe
RE: Airfoils
i was answering the OP from a steady-state viewpoint. maybe also a 2D viewpoint
RE: Airfoils
Not sure quite how good it is as it's description of fundamentally why an aerofoil generates lift isn't the one my prof taught at uni. However, it has a section on pitching moment.
For some reason I was thinkin the wing usually generated a nose up moment, I clearly am forgetting all I learnt in aero and need to re-read my old mechanics of flight book.
KENAT,
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RE: Airfoils
moment coefficent is essentially zero for any angle of attack.
Chambered produces negative moment coefficient. Essentially constant for any angle of attack.
Now, for a total system such as an aircraft, the center of lift relative to the center of gravity does produce a moment. This is often nose down which is balanced by the horizontal stabilizer.
I suggest looking up a typical NACA airfoil lift curve.