Posted 10-1-2004 at 11:33 PM

What is Air Foil?
Written by: Ahmad // Edited by: Michael

Excerpt from Wikipedia
"An airfoil (or aerofoil in British English) is a specially shaped cross-section of a wing or blade, used to provide lift or downforce, depending on its application. Airfoils have a characteristic shape which is that of a curved streamline, with a rounded leading edge and a sharp trailing edge.


Image of an airfoil and the motion of air across it.
The above is a classic airfoil shape that provides lift with minimum drag. To understand how this airfoil works, you must know the Bernoulli's Equation, which states that as the speed of a fluid flow increases, its pressure decreases.
Notice the the shape of the wing of the plane? The bottom of the wing is flat. But the top has a curved shape. Let's assume air particle "A" and air particle "B" were to be broken in to two, where "A" goes up and "B" goes down. The distance that "A" would have to travel in order to get to the other side of the wing would be relatively longer than the distance that "B" would have to travel due to the curved shaped side. Naturally "A" would want to get the other side of the wing at the same time as "B". Therefore, "A" would have to travel at a greater velocity then "B". Air particles with higher velocity have less air pressure so the higher air pressure created by the slower air particles in the bottom of the wing would create lift.
Don't matter if you copy but if it's for school, be careful.