|WikiProject Aviation||(Rated Start-class)|
this is rubish. it is a poor attempt to describe the venturi effect. to start with venturi lived before the invention of human flight. while low pressure air flow has a very small effect in gliders (most of the lift being provided by thermals, it is nothing at all to do with powered flight ! planes can quite hapily fly upside down without being sucked towards the ground. wings are purely a control surface and handy place to put things such as the fuel and engines. --188.8.131.52 (talk) 11:51, 5 October 2011 (UTC)
channelwing-effect? please a better explanation!
to my mind the channelwing-effect is not well explained here, or I just don't understand it well... but please consider my questions and may be give an answer for somebody like me:
the basic idea is: „It's the speed of air, not the airspeed!“ (german: "Es ist die Geschwindigkeit der Luft, nicht die Geschwindigkeit in der Luft.") that means, that also a conventional airplane with nearly horizontal, straight airfoils develops a lot of up-lift when the engines are running full speed. so if you fix a conventional airplane horizontally and allow it only to move vertically it should lift off when there is sufficient air-stream generated by sufficient engines (preferably propellers whith their axis right in front of the wing creating an extended airstream; not jets detached below the wing). right?
now, what does the channelwing specifically do?
first thought: the "sucking"-force-vectors should be at a right angle to the wing. so if the airfoil follows a half-circle the more you get to the upper edge (where the horizontal part of the custerwing continues) the more horizontally the vectors run... so the less useful they are for vertical lift.
so what may be the positive effect of the half-circle (which structurally is not very advantageous)? the thing that comes to mind is: it brings a longer part of the airfoil in contact with the high-speed-air-stream, which is round, than with a flat wing, because the a half-circle is longer than the diameter of a circle. and that seems to be advantageous, even if the half-circle is efficient only in the lower areas...
if a decisive component of the effect is to be that the propellor can not suck in air from below but just from above than I could also think of mounting a propellor above a flat wing right in the middle of it (or above the center of lift). so again with this aproach you do not catch the specific effect of the channelwing...