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Mess with your minds: A wind powered craft going faster than a tail wind speed.
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bdunham7:

--- Quote from: electrodacus on December 17, 2021, 09:19:57 pm --- is in violation of energy conservation.

--- End quote ---

What's that?
electrodacus:

--- Quote from: bdunham7 on December 17, 2021, 10:20:24 pm ---
--- Quote from: electrodacus on December 17, 2021, 09:19:57 pm --- is in violation of energy conservation.

--- End quote ---

What's that?

--- End quote ---

Energy cannot be created or destroyed just converted from one form to another.
Vehicle (any wind only powered vehicle) has no access to wind power when above wind speed directly downwind.
All tested vehicles the blackbird and the treadmill model show decrease acceleration rate after exceeding wind speed meaning they will get to top speed and start to decelerate after that but none of the tests run for long enough to show that so people proposed wrong theories about what happens.
 
PlainName:

--- Quote ---That energy storage device will be charged during the initial acceleration phase
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Where is the acceleration phase on the treadmill?
bdunham7:

--- Quote from: electrodacus on December 17, 2021, 10:31:56 pm ---Energy cannot be created or destroyed just converted from one form to another.

--- End quote ---

How would that be violated by a sail dissipating all or most of the wind energy and only transferring a small portion of that energy to the vehicle?


--- Quote ---The way pressure varies at the back of a sail / wall is exponential and that is perfectly matching that decreasing rate of acceleration shown using power and energy. Not to mention they perfectly match any experimental test.
You just think sail is low efficiency because you use incorrect formula.

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The formula used earlier that seems to be widely accepted as correct (the drag equation) is also exponential and doesn't diverge to infinity as the vehicle speed approaches zero.  In fact, it doesn't matter whether the vehicle is stationary or moving beyond how that changes the relative speed of the wind and vehicle. 

So now you are positing some new drag or sail formula that would give you an extremely high pressure and thus an extremely high initial acceleration for a 10m/s wind and a stationary vehicle.  So what would the pressure and acceleration be if you had an 11m/s wind and a vehicle moving at 1m/s?  Would that be different?

What experimental tests are you referring to? 
electrodacus:

--- Quote from: dunkemhigh on December 17, 2021, 10:41:06 pm ---
--- Quote ---That energy storage device will be charged during the initial acceleration phase
--- End quote ---

Where is the acceleration phase on the treadmill?

--- End quote ---

I think I explained that before here but it is when you put the vehicle on the treadmill.
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