NALSA confirms directly upwind record of 2.1 windspeed: http://www.nalsa.org/ F7PNSyAfCjk
Pictures and video from the official directly upwind record attempt:...
Doesn’t the frequency of the drive depend on how much thrust you need? How to avoid that it hits the boats wiggling frequency at some thrust setting?
They had some tests already, and unofficially came close to 2x windspeed, directly upwind:...
Not sure if I picture this correctly, but wouldn't this create periodic vertical reaction forces that would shake the vessel. I guess it doesn't...
Yes, that is a difference which makes it trivial to see for the turbine. For the piston/crankshaft arrangement it is more complex. Yes, just like...
Changing direction of some parts doesn't imply net energy loss Rotating parts like turbine blades are also changing direction (in two dimensions,...
http://en.wikipedia.org/wiki/Lift_%28force%29
Well, they have to comply with NALSA rules for sailing records. They cannot use any stored energy for propulsion (even if it was stored during the...
Hi Ingmar, Congratulation on your many successes in the WPV races. Do you think that you will ever reach more than 100% wind-speed given the...
That is a good way to think about it. Two boats that can achieve downwind VMG > windspeed can be connected to a single catamaran with two moving...
Dynamic soaring doesn't require any vertical flows (updrafts and downdrafts). It works with purely horizontal flows, if there is a velocity...
Bernhard Schmidt (http://en.wikipedia.org/wiki/Bernhard_Schmidt) tired to patent a Windmill driven upwind boat (Gegenwindschiff) in 1925. Patent...
What I actually meant there was just the power harvested by the moving turbine itself, which is unlimited regardless of the Betz limit. I wasn't...
If your turbine is moving upwind, then there is no limit on the power (in Watts) you can harvest, because you interact with a greater volume of...
I don't quite understand that part about exploiting the differences in disk torque to disk momentum. IMHO this mechanism exploits the velocity...
It has nothing to do with the density difference between water and air. It would work in two fluids of equal density as well.
Well, that would be a different record-category. This one is just about speed. Establishing a record-category based on wind speed multiple is...
You can not only go directly upwind. You can even go directly upwind faster than the wind. The simplified mechanics for a wheeled vehicle shown...
NALSA confirms 2.8 wind speed DDW From http://www.nalsa.org/: [IMG]