Merged DDWFTTW in a “Real” Wind

[EHocking]

Originally Posted by humber
Afraid not. If a real cart is moving at 10m/s, after one second it will travel 10m.
That is 10m of road will pass by. Same for 11m/s etc.
On the belt set at 10m/s the belt moves 10m, but the ">WS cart moves say 10.1m. The video shows a cart moving at 0.1m/s ( the visible motion) while the belt moves at 4m/s.

Since I have no idea which video you are referring to, where is it stated that the cart is doing 10.1m/s?

So the cart "moves" 4.1m as 4m of ground passes by.

And if this was so, the cart would move "up" (ie in the opposite direction the treadmill belt) at 1m in 10sec.

Uh. So? This merely demonstrates that the cart is capable of >WS DDW.

So. Which video are you referring to here? I see a number posted on YT by Spork, but can't see which one shows a cart moving at 0.1m/s on a treadmill.

 

[Jack by the hedge]

It was found by trial and error, and through sheer ignorance, mistaken for a genuine model of a cart in the wind rather than the machine that stays in place as I have described.

Do you want a medal?

In the wind, there will be forces that are not on the TM.

Forces like time variation of the wind; the forces of which Mr. NASA#2 declared: "it might be possible to extract a very slight amount of extra energy from the time variation of the wind ... But it is certainly not the dominant effect, which is much more simple and, (dare I say...) obvious." Are those the forces you mean?

 

[A.T.]

Since humber is not only quote mining the NASA engineer here, but outright lying about what he said I will post the entire e-mail from:
http://talkrational.org/showthread.php?p=1257363#post1257363

And?

Everyone, who doesn't suffer from a reading disorder, can see for himself that the NASA engineer is not saying, what you attribute to him (headwind drives wheels via prop), but in fact he says the exact opposite (wheels drive prop).

 

[A.T.]

There are tacking boats.

Any references about tacking with rotor driven boats?

Let's see what the NASA engineer said:

I have been an applied aerodynamics researcher at NASA Ames for 31 years. In addition, I grew up racing sailboats,
...
So I am well-acquainted with the performance of sailboats at downwind headings not directly downwind, and it is true that for sailboats, there is a significant benefit to boat speed to do that, primarily from the aerodynamic characteristics of sails. However, that effect is not in play to any appreciable degree on the DWFTTW cart, and if anything, acts to diminish the thrust on the propeller.

In other words, it performs best when DDW.

 

[humber]

So. Which video are you referring to here? I see a number posted on YT by Spork, but can't see which one shows a cart moving at 0.1m/s on a treadmill.

If you look, you will see that the cart moves about 0.1m in a second from the "windspeed" state. That is inexplicable in terms of the equivalent distance on a road. No matter, any TM ">WS" travel does the same.

 

[humber]

Any references about tacking with rotor driven boats?

Yes. Prop sails have been tried many times.

Let's see what the NASA engineer said:
In other words, it performs best when DDW.

He is wrong, and the chart says he is. His proposal is hypothetical and has never been tested. He also proposes that the result could be the product of crosswinds, gradients or wind instrument errors, and even suggests one. He missed a few.
That is why he suggests monitoring the motor current to find which way the energy is going, and so if the idea works or not.
There were supposed to be force gauges on the prop and wheel for the same purpose, but they were never completed.

 

[Michael C]

That is why he suggests monitoring the motor current will tell which way the energy is going, and so if the idea works or not.

And right after that he proposed an even simpler method:

"Even simpler is to just examine the drive chain while it is running, and see which side of the drive gears the chain is tight on. When you pedal a bike, the top leg of the chain is tight -- if the wheel of a bike is forcing the pedals to turn, the bottom leg of the chain is tight. On the DWFTTW cart, this simple test makes it easy to see that the wheels are indeed driving the prop."

 

[jduffy77]

There are no references to tacking props, because that is BS.
There are tacking boats.

There are literally hundreds and hundreds of references about tacking props. Just pick up any aerodynamic text book that discusses props. The word tacking was introduced to help folks with a sailing background (and the hard of thinking) understand what was happening.

You could safely make the statement that there are no references talking about the fact that smashing a margarita blender into your face as hard as possible would be inadvisable. The absence of references does not make it advisable and in fact is just a word game. The fact is that medical texts are full of discussions of all manner of contusions, lacerations and other head traumas.

 

[EHocking]

If you look,

At which video specifically?

you will see that the cart moves about 0.1m in a second from the "windspeed" state. That is inexplicable in terms of the equivalent distance on a road.

No it isn't, but until I know which particular example is being discussed I have no way of pointing out where you are making your error.

No matter, any TM ">WS" travel does the same.

Which (again) specific video shows the cart moving at 0.1m/s faster than the treadmill?

 

[jduffy77]

At which video specifically?No it isn't, but until I know which particular example is being discussed I have no way of pointing out where you are making your error.Which (again) specific video shows the cart moving at 0.1m/s faster than the treadmill?

He is talking about an absurdity, the distance the cart outpaces the wind by. It would be the same on the road if you measured the distance between the cart and a balloon in the wind. He does not understand frame of reference and therefore does not treat the belt as the ground. All the distances are exactly the same on the road and the belt.

 

[humber]

At which video specifically?

Find it. One of the early TM demos. But, any WS travel says you have a problem. Are you now claiming that the TM is not "proof" of >WS travel?

No it isn't, but until I know which particular example is being discussed I have no way of pointing out where you are making your error.Which (again) specific video shows the cart moving at 0.1m/s faster than the treadmill?

Make it 0.01m/s or 2m/s and explain how that can happen on a road.
ETA:
That the cart can move forwards more than the road moves "backwards"

 

[jduffy77]

Yes. Prop sails have been tried many times.
He is wrong, and the chart says he is.

This is an unequivocal lie.

His proposal is hypothetical and has never been tested.

This is an unequivocal lie.

He also proposes that the result could be the product of crosswinds, gradients or wind instrument errors, and even suggests one.

And then dismisses it in order to try and preempt discussion of it by nitwits.

 

[EHocking]

Find it. One of the early TM demos. But, any WS travel says you have a problem. Are you now claiming that the TM is not "proof" of >WS travel?

Make it 0.01m/s or 2m/s and explain how that can happen on a road.

Ah. So yet another of your strawman arguments.

Invent some data. Debunk based on invented data.

 

[A.T.]

Any references about tacking with rotor driven boats?

Yes. Prop sails have been tried many times.

Sorry, that wasn't the question. Try again:

Do you have any references which show, that rotor driven boats are using tacking to improve their performance?

 

[jduffy77]

Make it 0.01m/s or 2m/s and explain how that can happen on a road.
ETA:
That the cart can move forwards more than the road moves "backwards"

The road moves backwards the identical distance as the TM.

 

[jduffy77]

Ah. So yet another of your strawman arguments.

Invent some data. Debunk based on invented data.

He is not inventing data in this case, just misinterpreting it.

 

[EHocking]

He is talking about an absurdity, the distance the cart outpaces the wind by. It would be the same on the road if you measured the distance between the cart and a balloon in the wind. He does not understand frame of reference and therefore does not treat the belt as the ground. All the distances are exactly the same on the road and the belt.

Oh, I've quickly realised all of the above from my participation in this and the earlier thread!

I was just wanting humber to cite the actual video example he used in his adamant "debunk" .
Apparently he does not have one.

 

[jduffy77]

Oh, I've quickly realised all of the above from my participation in this and the earlier thread!

I was just wanting humber to cite the actual video example he used in his adamant "debunk" .
Apparently he does not have one.

oh, sorry.

 

[spork]

This is an unequivocal lie.
This is an unequivocal lie.

That is what humber does. It's perhaps his favorite tool in his bag of tricks. And he's found a forum here at JREF where continuous lies and defamation are acceptable.

But when you have absolutely nothing, you have nothing to lose. humber's only reputation is that a physics crank, internet troll, and liar. He has never accomplished a thing in his life, so nothing can be taken away. His only hope is to try to pull others down to his level.

 

[A.T.]

He also proposes that the result could be the product of crosswinds, gradients or wind instrument errors...

No. He doesn't propose that this is what causes the result. Rather the opposite: He makes very clear that none of the above is needed to explain the result:

It’s funny to me how hard people work to contrive an alternative explanation for something that is actually fairly simple: The propeller thrust is greater than the wheel drag, because the apparent (relative) wind speed is slower than the ground speed.
...
I can’t help make an analogy to someone that would argue with Einstein’s proposition that gravity is just the curvature of space-time because they don’t understand it, rather than accept that they don’t understand it and try to fill their knowledge gap.

This is a friendly way to say: "You are crank who tries to Teach the Controversy because you fail to understand how it works."