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The unusual wind-powered car hit a top speed 2.86 times faster than the wind during one recent run...
Don't all landyachts/iceyachts do that ?
Wouter
Yes, but with a landyacht to go DDW you would have to built up apparent wind first.
As I understand it this things starts riding downwind from the start.
As I understand it this things starts riding downwind from the start.
Landyachts and this thing do share some features - but I agree that this device is a little different. It points straight downwind and can go faster than the wind. I think a landyacht would still need to maintain some angle (or maybe not?) <img src="<>/crazy.gif" alt="crazy" title="crazy" height="15" width="15" />
A couple of years ago we discussed this at great length here on the forum - the concept of this vehicle is pretty difficult to wrap your head around...but it works. As they pointed out in the article, we have a hard time with this concept because we have direct experience that if we are, for instance, on a bicycle riding downwind at the same speed as the wind - we feel no breeze. Our minds figure this means that there is no power to be had and that there would be a physical wall to traveling faster than the wind. However, these devices don't use the wind to turn the propeller. The propeller always turns against the wind. Initially, the wind drag over the stationary prop starts the vehicle moving forward. As the wheels start moving over the ground, a gearbox transfers that wheel power to start turning the prop (remember that the prop is turning against the wind). As the vehicle builds speed, the prop turns faster and pushes against the wind harder. At this point, the breeze coming off the prop is faster than the wind so it's literally
pushing
itself off the available wind. Because of this, it does not see a dead zone when the vehicle matches the wind speed - the propeller is pushing against the wind which develops a forward force on the car - the vehicle continues to accelerate, the wheels, gearbox, and propeller turn faster. There IS a limited amount of power available that's directly relative to the wind speed and the drag efficiency of the vehicle but it's not limited TO the windspeed - it's limited to the drag of the wheels/bearings/gearbox/propeller/etc. When the drag the vehicle is experiencing is equal to the amount of energy it's available to harness from the wind, it holds a steady speed...in this case, almost 40 mph.
voodoo! witch craft! burn it!
actually its very cool. but your gonna have a hell of a time at mcd's drive through window