Here is a pretty good description of how it works:
<http://scienceblogs.com/goodmath/2008/12/the_real_bozo_attempts_to_aton.php>
Ron
--On Wednesday, September 22, 2010 1:12 PM -0400 Lawrence de Bivort
<debiv...@evolutionaryservices.org> wrote:
Sailboats vary enormously in terms of their favored point of sailing. I would
guess that most
sailboats do best with the wind on their beam (90 deg.) My boat is best on
that point, and I can
also sail into the wind to about 28 degrees without pinching, which is
exceptionally. Downwind
is slow for me, so I often tack downwind, keeping main and gennie filled.
I wonder what race committees will say when a sailor shows up with this rig.
Thinking of John's
explanation, though, I suppose it will not work as there won't be any torque
transmission from
the wheels to the prop.
Right, John?
Cheers,
Lawry
On Sep 22, 2010, at 1:02 PM, OrionWorks - Steven V Johnson wrote:
From John Fields,
...
Note that with the wind pushing the cart and the pitch of
the propeller as shown, the wind would, intuitively, be
forcing the propeller to rotate counter-clockwise as
viewed from the rear of the cart.
However, such is not the case.
What's really happening is that the wind is pushing on
the prop, forcing the cart to move forward, and the torque
generated by the wheels is coupled to the prop in such a
way as to cause the prop to rotate clockwise when viewed
from the rear.
This direction of rotation makes the prop a "pusher",
and will increase the apparent force of the wind.
As long as the wind is blowing from the rear, the cart
will accelerate until it reaches wind speed, when the
wind speed will effectively be zero.
However, because of the prop's action as a pusher, the
cart will be going a little faster than wind speed, at
wind speed. Then, as soon as the prop feels the
headwind it'll stop being a propeller and will become
a turbine, driving the wheels and accelerating into the
headwind until, eventually, everything settles out and
the cart reaches its speed limit.
Well, I'll be keelhauled! Thanks for the clarification John.
My previous suggestion of using a "control" vehicle fitted with a
Viking-like sale is woefully inappropriate. It would be more accurate
to describe this vehicle's prop as TACKING through the wind. As most
sailors know, a sailboat tends to sail the fastest when sailing at an
angle of around 45 degrees INTO THE WIND. (I think maximum dynamics is
approx 45 degrees into the wind. Feel free to correct me on that
point, maitees.) The point being: Sailing closer into the wind seems
counter intuitive but it's the truth - insofar as sailboats are
concerned.
I can see it now. Sailors take note! This opens up a whole new
dimension to regatta races. You heard it here first!
Where's my parrot.
Regards
Steven Vincent Johnson
www.OrionWorks.com
www.zazzle.com/orionworks
