From the paper
Power and lift
In aerodynamics, the subject of power requirements is seldom considered. Some introductory textbooks do not even have power listed in the index. In aeronautics this discussion would be about drag, which is a retarding force, the effect of which is proportional to the speed of the airplane. Unfortunately, drag is difficult to derive and is usually presented without derivation.
Which is a shame, but joins some other problems which make the standard model problematic.
One if which, imo, is the immediate suggestion that it is tha air that moves, rather than the wing, which although sustainable logically (albeit 'visually'), adds confusion to the model when presented as introduction...
Because that would suggest the energy is bound in the airmass, rather than in the propulsors. It is reasonable to assume, if the airmass is presented as the energetic mass, that "flow" is present. It is not. Not initially, and that is what the authors isolate as damning of the model. They pointedly state "the acceleration is unexplained".
The air is compressed, and then accelerated downward aft of the trailing edge of the wing. Vortices and chaotic turbulence are artifacts of the wings development of "lift". Which brings up perhaps my most serious criticism, that somehow the aircraft is "pulled up by suction". That to me is ludicrous, as low pressure cannot be created in this instance without compressing (pressurizing) airmass somewhere close by. In this case, it is critical to look to the work as "push" NOT "pull".
It is not incorrect to say that "lift" is developed not by flow, but by preventing it.
Preventing flow into low pressure zones is what wings do, and what makes them useful.
Last edited by Lyman; 14th Nov 2012 at 16:35.