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Mess with your minds: A wind powered craft going faster than a tail wind speed.
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Labrat101:

--- Quote from: Kleinstein on September 04, 2021, 11:05:16 am ---The experiment with the treadmill is the controles environment "wind tunnel" replacement, just with a different system of reference.

--- End quote ---
No .. Not the same .. you just contradicted your self from a previous post .
Psi:
That was my point, not everyone agrees that a treadmill is a valid analog.
So a wind tunnel seems like the only way to convince those people.
Labrat101:

--- Quote from: Psi on September 04, 2021, 11:54:54 am ---That was my point, not everyone agrees that a treadmill is a valid analog.
So a wind tunnel seems like the only way to convince those people.

--- End quote ---
. There seems to be a fixation on treadmills etc.
I will give a just a few reasons why they are not used other than exercising the Dog .
First they have a very high friction as the belt runs over the rollers the surface gets warm to hot .
the bottom of the belt that hangs down at the bottom has to be loose . So it flaps .
Having to moving surfaces running in parallel in opposite directions causes side air distortion  and turbulence.   .
Even at airports they did away with this due to belts getting hot . Now they use just rolling beds .. Belt-less.
In other places the belts were replaced with slated belts that were self cooling ..
The aerospace industry , Lockheed , NASA , and all the others .
Don't use this in a wind tunnels or for replacing the use of a wind tunnel due to there significance and disturbance in testing.
The test item in a wind tunnel is usably suspended . in the car test rollers are used and the wheels are placed between 2  controlled
rollers . 2 at the front and 2 at the back . and are computer controlled . The rollers are covered by a plate so no other side effects
mess with the final tests .

Treadmills etc work great on paper and for demonstrating  science projects . And not to for get the GYM .
or moving lots of odd shaped stuff from containers etc .
So Please get over the treadmill . .. hamsters likes them .
Psi:
Don't get me wrong, i think the effect is real and that the treadmill is showing the effect in action.

But if the treadmill demo doesn't convince some people then it's best to find some other way to demonstrate it, rather than arguing back and forward that the treadmill does in fact prove it.
Brumby:

--- Quote from: Labrat101 on September 04, 2021, 12:28:19 pm ---. There seems to be a fixation on treadmills etc.
--- End quote ---
That's because a treadmill is a convenient mechanism to demonstrate the principle.  This is because of the validity of the concept of "Frames of reference".


--- Quote ---I will give a just a few reasons why they are not used other than exercising the Dog .
--- End quote ---
This will be entertaining....


--- Quote ---First they have a very high friction as the belt runs over the rollers the surface gets warm to hot .
--- End quote ---
So?  How does that affect things?


--- Quote ---the bottom of the belt that hangs down at the bottom has to be loose . So it flaps .
--- End quote ---
So?  How does that affect things?


--- Quote ---
Having to moving surfaces running in parallel in opposite directions causes side air distortion  and turbulence.   .
--- End quote ---
So?  As a factor that is somewhat minimal, how does that affect things?


--- Quote ---Even at airports they did away with this due to belts getting hot . Now they use just rolling beds .. Belt-less.
In other places the belts were replaced with slated belts that were self cooling ..
--- End quote ---
So?  The temperature of belts is not going to affect the experiment unless they've burst into flames or gone so tacky as to be unable to allow rolling.  This is a non-argument.


--- Quote ---The aerospace industry , Lockheed , NASA , and all the others .
Don't use this in a wind tunnels or for replacing the use of a wind tunnel due to there significance and disturbance in testing.
--- End quote ---
Don't see this being significant for the scale of test we are talking about.


--- Quote ---The test item in a wind tunnel is usably suspended . in the car test rollers are used and the wheels are placed between 2  controlled
rollers . 2 at the front and 2 at the back . and are computer controlled . The rollers are covered by a plate so no other side effects
mess with the final tests .
--- End quote ---
OK.  Fine.  The rollers are a perfect analogy for travelling over the ground (Just as a treadmill belt is, BTW) - but the only thing is that they constrain the movement of the wheels.  In such an experiment, the rollers would need to be programmed to increase speed to match the performance of the vehicle, while the wind speed remains constant.

Do that and you'll find the Blackbird does work.


--- Quote ---Treadmills etc work great on paper and for demonstrating  science projects . And not to for get the GYM .
or moving lots of odd shaped stuff from containers etc .
So Please get over the treadmill . .. hamsters likes them .

--- End quote ---
OK - a dismissive wave of the hand and it all goes away...?  That is classic denial.
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