posted on Jun, 7 2007 @ 02:02 AM
Ok this is what I think
I've understood so far.
-The Bernoulli explanation exists and correctly explains that differences in air-speeds are directly proportional to differences in air-pressure. The
Bernoulli explanation works for all fluids and gases.
-Restrictions are that it only works with incompressible fluids (low speeds).
-You don't assume changes in heat.
-This explanation applies to all physics not just aerodynamics.
-The longer path explanation states that the Bernoulli phenomena is a result of "air particles starting at the front of the wing (at the same time)
have to meet eachother exactly same time at the back of the wing."
-There is no science to this. No law in physics demand that the two particles have to meet eachother the same time at the back of the wing. This makes
the "longer path" explanation faulty.
-Therefore the conclusion is that the Bernoulli phenomena exists, it just isn't a result of the longer path explanation.
I assume that tip vortex is created by the higher air-pressure (under the wing) that can escape around the tip above the wing where the pressure is
lower. Thus creating in a sort of a spin. This is also the reason for turbulence.
In your NASA picture there was two tip vortexes. How come? The air can't escape around the wing at the end that is close to the fuselage?
It's the bound vortex that actually lifts the plane. Above the wing the bound vortex "goes with the flow", thus creating higher air-speed and lower
pressure (Bernoulli explanation).
Under the wing it doesn't go "with the flow" but against it, thus slowing the airflow and creating higher pressure. This leads to creation of lift
with the F=p*A formula.
Now if this is correct, I still don't understand why bound vortex slows the airspeed down under the wing but increases it above the wing??
[edit on 7-6-2007 by Figher Master FIN]