[quote]Bill Roberts wrote:
You certainly could achieve some increase in wind speed with some arrangement or other: I would suppose the funnel would work though I have no experience with that.
I can attest that when you are under the wing of a DC-3 on the ramp, wind gusts are considerably accelerated. (Which once provided the amusing enlightenment of revealing that a fellow mechanic, who was very hairy guy overall, only in his very early 30s, and always wore a baseball cap, was quite bald for almost all of the until-then-hidden cranial area.)
Basically, a flat board at an angle to the ground, some height above the ground, would be the equivalent. A pic of a DC-3 on the ground would give an idea of angle and height, relative to chord (width) of the wing or board.
But the funnel might work as well. Probably would as a guess.
However, it would not work as well as having blades extending that same diameter.[/quote]
I’m not sure I agree, wouldn’t I be collecting the energy from a higher percentage of the air that moves past my rotor? I mean in a typical 3 blade design, you are only gathering the energy from the wind hitting the blades, which is a small amount. But if it was all funneled to a paddle wheel design windmill with closely spaces blades, nearly all of the wind would be applying force to the blades. You would lose some efficiency due to having no aerodynamic effect, but aerodynamic effect cannot INCREASE the amount of energy a given wind has, only make the turbine more efficient. So being 50% more efficient at collecting 30% of the wind cannot be better than collecting 95% of the wind. And with the Mag Lev Bearing, efficiency should be increased on my design, so maybe the airfoil would only be 25% more efficient, or maybe less. Won’t know untill I get working prototypes.
Orion - I could put spiral fins inside the funnel, but I am not sure it would have a positive effect on the blades. If the air coming out the back of the funnel was spinning, I think even though more air was coming through, it might not be going in a straight line.
Now with a big enough funnel and the spiral fins in it to produce a vortex, you could cut slits in the funnel and actually mount small paddle wheel rotors halfway into the funnel and catch the swirling wind in a predicatable manner. You could have several of them sunk into one funnel. Than might be another idea worth checking into. You could get 3 or 4 cracks at a given strech of wind.