Remember the POAT (plane on a treadmill) thread from a year or so ago? Got another one: Can a device be built that can travel downwind, faster than the wind, powered only by the wind, steady state? JB
It can't go faster than the wind, if its travel direction is exactly down wind (parallel to the wind velocity vector). If it is allowed to travel at a down wind angle, then yes. The wind will travel around the curvature of the sail at a faster rate (Bernoulli's) and essentially "pull" the vessel faster than the downwind velocity.
I have built, and can demonstrate on demand a vehicle which can travel directly downwind, faster than the wind, powered only by the wind, steady state. http://www.youtube.com/watch?v=Vjt6G8D4x0k
Nope. I don't buy it. You are imparting energy, through the wheels and into the prop, from the treadmill. That's not wind power. The fact that it goes faster than the treadmill is not important. You have created an energy transfer from the treadmill motor, not the wind. Actually blow wind at it, then show it going exactly up wind (or exactly down wind) faster than the wind, with no treadmill. Then patent it! Maybe I'm just a born skeptic?
Your experiment would imply that your little gizmo produces more energy that is uses. But we already that isn't possible. I think what you have done is turn x revolutions of the wheel into x revolutions of the prop. Similar to the leverage of a pully or lever.
It doesn't imply that, and we don't imply that. The device is powered by the relative motion between air and rolling surface. Shut off the 'wind' and the device stops. Yes we do. JB