Owain
Thanks for your reply.
After a while the graph seems to have some sense. Lately I have lost my ability to interpret graphs. I was good at that some time ago, but I'm growing old... What is on the vertical axis, exactly? Anyway I think I understand what you mean. Comes to my mind a graph with those lobes of pressure in the upper and lower surfaces.
So symmetrical airfoils never create any couple, but cambered ones always do, Right?. I will accept that as an empirical fact, because a theoretical explanation of it can be extremely complicated, I deem.
Can we consider the effect of the airstream on the wing as producing a total reaction plus a pure moment (a couple) that we call Aerodynamic Moment?
In case this is affirmative, the point at which the Lift is considered to be acting (i.e. the CP)... Does it take into account that couple, too? or you have to consider the moment of Lift (acting on the CP) about the CG and then add "the couple" or aerodynamic moment to find the total pitching moment effect?
PD
I think that maths are a kind of language but it is is good to frequently translate it into normal words
Last edited by Microburst2002; 18th May 2012 at 10:31.