Quote:
Originally Posted by ttoyoda
I must disagree. A wing with a flat bottom may generate lift from the bottom, but that is only if it has a non-horizontal angle of attack.
The length of the air path is not relevant, even though that is the way many people explain it. Lift is caused by curvature of streamlines. In any curving streamline, the air pressure is lower on the inside of the curvature, and higher on the outside of the curvature.
This paper explains the idea, and it is permissible to glaze over the math. 
http://ocw.mit.edu/NR/rdonlyres/Aero...0/4liftgen.pdf |
Wow. That's why I'm not an engineer.
Still, I would think that if having a very flat bottom on a car would have any seriously adverse effects outside of salt flat speeds, someone here would have experienced it.