> > All new airliners of Airbus or Boeing make and all top bizjets, have
> > low drag "supercritical wings", with almost flat upper surface and
> > curved lower surface (to host wing beam and fuel)!
> >
> > I have never seen Scientific American explain that wing and why it
> > physically create Lift!
>
> A supercritical wing is, by definition, designed to operate in a
> compressible flow regime. You can throw Bernoulli out the window for
such
> wings.
>
> They still generate lift the same way as all other wings; they induce a
> circulation in the airflow. They have a "fat" shape to control adverse
> transonic effects and prevent shock separation on the upper surface from
> occuring too far forward.
Keep in mind that the air is not constrained to follow the surface
contour perfectly. Smoke tunnel test photos are very revealing. The
airflow once you get a fair fraction of the chord away from the surface
begins to look the same on almost any airfoil generating lift.
To use Bernoulli's law, you must use it in small local regions, then
integrate the pressures completely around the foil.
All camber does is ****ft the lift vs aoa curve right or left, not up
and down. A flat plate generates lift, so do reverse cambered
airfoils. But they do so over different ranges of AOA, and the PEAK
lift coefficient will differ from airfoil to airfoil. At lower AOA,
all airfoils generally have the same change in Cl per change in angle.
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