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

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Labrat101:
Any thing that spinning will ,& does also produces centrifugal force this has also seams to be forgotten.

electrodacus:

--- Quote from: lordium on December 30, 2021, 07:32:17 am ---
We lose some power to spin the propeller, but we gain it (some?) back because it is now easier to move forward.
like we decrease drag, so we can go a little faster using same power.
I see it like we move energy around in the system, but the total is still pretty much the same (minus some loss here and here).
We make something less efficient (spinning the thing isn't free) but make something else more efficient (lower pressure infront of us, woho here we come).
so the total energy is the same for the 2 cases, but the speed isn't. How much difference? Now is where all the %'s come in.
But I still see it as "possible" to go faster without "cheating". Or where did my thoughts go wrong?

--- End quote ---

The only source of energy is wind.
Wind can power the vehicle only as long as vehicle speed is lower than wind speed.
To exceed wind speed you need to store energy else is just not possible for the vehicle to exceed wind speed.
It is simple to test just wait until vehicle acceleration speed drops to zero then see how vehicle decelerates.
No test has done that so with the incomplete tests come wrong conclusion about what the test showed.

IanB:

--- Quote from: lordium on December 30, 2021, 07:32:17 am ---But I still see it as "possible" to go faster without "cheating". Or where did my thoughts go wrong?

--- End quote ---

You didn't go wrong anywhere. For a simple sail, you take the difference between vehicle speed and wind speed. When there is a propeller connected to the wheels, then you have wind speed minus vehicle speed plus propeller speed. You are not getting something for nothing as the vehicle is still being pushed along by the wind, and all the power required is coming from the wind.

It's a bit like gearing on a bicycle. If you change to a higher gear, you can go faster, but you have to push harder on the pedals. As long as the wind can push hard enough, the vehicle can keep going faster.

cgroen:

--- Quote from: electrodacus on December 30, 2021, 07:45:32 am ---The only source of energy is wind.
Wind can power the vehicle only as long as vehicle speed is lower than wind speed.
To exceed wind speed you need to store energy else is just not possible for the vehicle to exceed wind speed.
It is simple to test just wait until vehicle acceleration speed drops to zero then see how vehicle decelerates.
No test has done that so with the incomplete tests come wrong conclusion about what the test showed.

--- End quote ---

Repeating something that is wrong over and over and over does not make it right.
I'm extremely impressed with the knowledgeable people here that tries again and again to make you realize that you are soooo wrong. It takes an impressive amount of patience to do what they do.
Now, I could handle it if you were "just wrong", but the "god-like" way you try to convince people about that they are wrong and you are right "because you say so", is really something that turns my stomach around  |O

electrodacus:

--- Quote from: cgroen on December 30, 2021, 08:45:43 am ---
Repeating something that is wrong over and over and over does not make it right.
I'm extremely impressed with the knowledgeable people here that tries again and again to make you realize that you are soooo wrong. It takes an impressive amount of patience to do what they do.
Now, I could handle it if you were "just wrong", but the "god-like" way you try to convince people about that they are wrong and you are right "because you say so", is really something that turns my stomach around  |O

--- End quote ---

I'm sorry if you can not understand complex dynamic interactions.  The only way it will convince you is a test.
Tho even with a test you may not understand what happens as I showed a very clear example for the direct upwind version and people still try to find some other alternative explanations of what happens when it seems super clear what it happens there.

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