3 ms·
My point about the Bernoulli effect is that there is no physical reason why the upper flow should move faster than the lower flow and in fact testing shows that
by lowkey 5y ago
My point about the Bernoulli effect is that there is no physical reason why the upper flow should move faster than the lower flow and in fact testing shows that they do not.
- jjk166 5y agoThe upper flow does move faster, and must for the sake of vortex production.
- lowkey 5y agoPlease explain what you mean here in simple language. I don’t understand how you conclude that the upper flow must move faster and I don’t understand how it relates to vortex production.
- jjk166 5y agoTo get a force acting upwards on the wing, there must be a downward reaction on the airstream. This downward force on the airstream bust change its direction. This change of direction is a rotation about the airfoil. Specifically a downwards rotation. The airstream moving above the centerline of this rotation is moving in the same direction, and thus will be accelerated faster. The airstream moving below the centerline of this rotation is moving in the opposite direction, and so will be decelerated to a slower speed. The center of this rotation happens to be along the camber line of the airfoil, so all the air above the camber line (ie over the top of the airfoil) must move faster, while all the air below the airfoil must move slower. The vortex is just the bulk rotational movement of the airflow. In fact, the airfoil can be replaced by anything that will generate the same vortex, like a rotating cylinder.