Merged DDWFTTW in a “Real” Wind

[humber]

I'd like to congratulate you two on finding one another. I think you'll be very happy together.

And you were 100% sure that within 20 minutes you could convince Dr Camp and so many others.

Steve Smith
"There are those that get quoted as expressing a certain opinion, and the quote persists long past the time that that opinion is still held. I’m quite certain that if you give me 5 minutes at the chalk board with a Nobel laureate physicist, I can convince him of the validity of the analysis for the DWFTTW cart."

And the idea of the air lever came from him. It was not part of your Harrypothesis prior to that.

But Steve Smith does understand the claim better than you.
Steve Smith
"When Mr. Cavallaro is here, I will raise this hypothesis about the effect of small variations in wind direction. I think we can quickly dispel it on his demonstration treadmill by moving the fan in small amounts to one side, and I expect to see the cart slow down."

And what happens when the fan is moved to the side? Can you test that and keep the cart on the belt?

( But also a bit evasive, because the wind variations of the trial are far from small)

 

[humber]

This makes at least as much sense as any of humber's posts. At least there's a chance this one does not contain a lie. We may never know.

He posted that his opinion about the C of E does not mean that ddwfftw is possible.
His dismissal of the TM is unequivocal,

As I said, I did not ask, but he volunteered this

"I don't agree that the treadmill is an equivalent experiment but I don't think that is material either.
I've more or less convinced myself that it doesn't in principle violate conservation of energy but I have difficulty working my way through a plausible mechanism to make the thing work."

The TM or the cart? I know the mechanism for the cart.

What was the question put to him cart, TM or a mixed bag?

 

[EHocking]

...I've more or less convinced myself that it doesn't in principle violate conservation of energy but I have difficulty working my way through a plausible mechanism to make the thing work...

Therein lies your problem.

The rest of us have.

 

[humber]

How big would a TM have to be before you could not tell if you were standing on a TM or a road?

Irrelevant, but can you step off the road onto a moving ground?
The TM has another frame. Air, road and ground.

The cart is said to go faster than the road. No vehicle does that. Strictly one to one.
It violates its own premise.

 

[humber]

Therein lies your problem.

The rest of us have.

Dr Camp hasn't. It was his quote not mine.

And I know the mechanism for the cart. From observing behaviour that you missed, I calculated the force of the belt on the cart to be 0.04N.
Mender measured "4grammes" .04N.
I win.

 

[EHocking]

..The cart is said to go faster than the road. No vehicle does that. Strictly one to one.
It violates its own premise.

Of course it does - because the "cart going faster than the road" is a strawman premise invented by you.

No one else thinks this.

 

[Subduction Zone]

Irrelevant, but can you step off the road onto a moving ground?
The TM has another frame. Air, road and ground.

The cart is said to go faster than the road. No vehicle does that. Strictly one to one.
It violates its own premise.

Evidence that Mr. Flat Earth does not yet understand what a frame of reference is. humber, nothing "has" a frame of reference. Or in the words you have heard so many times, humber wrong try again.

 

[humber]

Of course it does - because the "cart going faster than the road" is a strawman premise invented by you.

No one else thinks this.

When a tyre is on the road and does not slip, the tangential speed of the tyre at the surface, is the same as the road. That is, one meter or tyre, results in 1m of forward motion. The TM breaks that rule, and the only way it can do that is if it slips.

 

[humber]

Evidence that Mr. Flat Earth does not yet understand what a frame of reference is. humber, nothing "has" a frame of reference. Or in the words you have heard so many times, humber wrong try again.

The GT is a ruse to sell a machine derived by trial and error.
Ask to see any mathematical proof, or a calculation of any sort.
Other than of course, a-b =c.
You will need to refute the calculated and measured 0.04N force.

 

[spork]

Of course everything humber posts is either a lie or just plain wrong. But I'm pretty sure everyone here already knows that.

 

[humber]

Of course everything humber posts is either a lie or just plain wrong. But I'm pretty sure everyone here already knows that.

The quoted lines are from the post that you put up at TR.
The rest is verbatim from Dr Camp.

If is a fact that you used ground power prior to the air lever. If you can find a post that contradicts that, then go ahead.

If air is blown over the prop from the front, the cart will advance up the belt.
A hairdryer close to the prop will show that.
You said that would not happen, which contradicts the current theory, but not the theory of the time.
In your submission, you say that crosswinds will slow the TM cart, and that is what Steve Smith thinks. And what happens?

And the 0.04N is a matter of record.

 

[I Ratant]

Yeah, when below windspeed. You needed a test to see that?

.
Well, yeah. I left the thing there for a good 15 minutes with the wind coming and going, and it never budged.
That is the starting point for the test sequence.
What is the minimal amount of equipment that the wind will not affect.
Then add the prop, fixed.
Then free the prop.
Building up to the final test condition is always worthwhile.
Lockheed lost their High Technology Test Bed C-130, after it had set a few world records for weight to altitude... on a simple ground test, killing everyone on board.
The test procedure was flawed, they didn't start simple and work up.
The F/A 18E was cursed with a severe wing drop discovered on its 7th flight.
The E was merely a scale-up of the previous versions, which didn't have the problem, which was quite serious.
It required many test flights to discover the cause, and then the fix*.
Rutan's Proteus experienced shaking and vibration when lowering the landing gear as a speed brake..."something akin to the end of the world as we know it" according to the pilots.
The first fix was.."significantly worse than the end of the world".
At the time of the report*, a proper fix was still being worked on.
NASA is using that plane today for UAV refuelling tests, so I expect that problem has been satisfied.
Testing the envelope of a product should always include the bare minimum configurations, just to build confidence as the testing gets more "interesting".
When introducing commercial pilots to the Tristar, their first attempts at full stalls were quite "interesting", with the plane gyrating and falling a good 5000 feet. With experience the altitude loss could be kept to about 1500'.
Which I always kept in mind when we were doing low altitude (<1000') over the ocean, testing one motor out handling and minimum control speeds.
.
* 1998 Report to the Aerospace Profession" XLII Symposium Proceedings, The Society of Experimental Test Pilots.

 

[I Ratant]

For further tests you should try to move the streamer out of the propeller circle. Above or better at prop hub height on the side.

A interesting challenge would be a simple cart like this, that stabilizes itself in the downwind direction, below and above wind-speed.

.
It's a tad reluctant to start, more so with the wind hitting the face of the prop.
Owing to the setup I had for the test, the wind began to curve around the side of the house as the cart moved out of the gap between the house and the shed and the cart would turn to follow it. It runs straight when pushed in zero wind.
A longer run would be interesting.
It made no difference which way the cart was pointing relative to the wind.
It always moves downwind, faster with the prop's rear getting the wind.
And, the freewheeling prop is rotating "backwards" relative to the prop on the carts with the drive wheel connection.
Would my thing move into the wind, I don't know.
Making the shafting and gearing between the prop and wheels would take too much effort and interest.
I'll just accept the configurations that work as proving the principle.

 

[spork]

humber continues to lie (and everyone knows it).

.
Well, yeah. I left the thing there for a good 15 minutes with the wind coming and going, and it never budged.
That is the starting point for the test sequence.
What is the minimal amount of equipment that the wind will not affect.
Then add the prop, fixed.
Then free the prop.
Building up to the final test condition is always worthwhile.
Lockheed lost their High Technology Test Bed C-130, after it had set a few world records for weight to altitude... on a simple ground test, killing everyone on board.
The test procedure was flawed, they didn't start simple and work up.
The F/A 18E was cursed with a severe wing drop discovered on its 7th flight.
The E was merely a scale-up of the previous versions, which didn't have the problem, which was quite serious.
It required many test flights to discover the cause, and then the fix*.
Rutan's Proteus experienced shaking and vibration when lowering the landing gear as a speed brake..."something akin to the end of the world as we know it" according to the pilots.
The first fix was.."significantly worse than the end of the world".
At the time of the report*, a proper fix was still being worked on.
NASA is using that plane today for UAV refuelling tests, so I expect that problem has been satisfied.
Testing the envelope of a product should always include the bare minimum configurations, just to build confidence as the testing gets more "interesting".
When introducing commercial pilots to the Tristar, their first attempts at full stalls were quite "interesting", with the plane gyrating and falling a good 5000 feet. With experience the altitude loss could be kept to about 1500'.
Which I always kept in mind when we were doing low altitude (<1000') over the ocean, testing one motor out handling and minimum control speeds.
.
* 1998 Report to the Aerospace Profession" XLII Symposium Proceedings, The Society of Experimental Test Pilots.

... and I Ratant gives us a lecture about testing, because he's concerned the downwind cart might have killed the pilot if it hadn't first been tested without a spinning prop. Interestingly enough - IT HAD. We tow tested it on the runway at New Jerusalem several times to make sure the basic vehicle dynamics were sound.

I find the defense of testing a foam cart with a freewheeling prop extremely lacking - particularly for a guy that 20 pages ago shamed us for even discussing this pointless topic. But to be fair, he has taken pointless to a whole new level.

 

[I Ratant]

I was curious about the bias in direction. If that was due to the prop, or the effect of the chassis. When that faces the wind, it can deflect or take energy from the incoming free-stream.
Of course, the prop will work better as a sail when it turns. When fixed, the depleted air, arrives at the other side of the prop, so you have something like Betz's limit at work. But, a turning prop moves the blade into fresh air.
I have a geared prop but use a fan. It behaves as you describe.
It won't move forwards on the chassis alone, but the prop adds a sail when the prop is free of the wheels. But, when geared, it can go towards the fan, but slower.

.
I won't bother adding the gearing and connections.. too much effort, too little interest.
See the previous post answering A.T.

 

[jduffy77]

Irrelevant, but can you step off the road onto a moving ground?

What do you mean? The ground is obviously moving but you don't say relative to what. 65000 mph or so relative to the sun.

The TM has another frame. Air, road and ground.

Nonsense. Road and ground is the same thing. How big would a TM have to be before you could not tell if it was a road or a TM? Or if it helps you; how small would you have to be?

The cart is said to go faster than the road. No vehicle does that. Strictly one to one. It violates its own premise.

I cannot parse this Humberese. The cart goes faster than the wind. Are you talking about if you lived in a balloon?

 

[GlennB]

When a tyre is on the road and does not slip, the tangential speed of the tyre at the surface, is the same as the road. That is, one meter or tyre, results in 1m of forward motion. The TM breaks that rule, and the only way it can do that is if it slips.

Ah now I see. Wheel slip is an advantage and can make you go faster than normal physics allows?

Excuse me. I need to lie in a darkened room and listen to whales singing on my headphones.

 

[spork]

.
Owing to the setup I had for the test, the wind began to curve around the side of the house as the cart moved out of the gap between the house and the shed...

That's the real science you were telling us about - huh? The "science" the investors would insist on.

A longer run would be interesting.

I assure you it would not.

It made no difference which way the cart was pointing relative to the wind. It always moves downwind, faster with the prop's rear getting the wind.

Interesting indeed - much like an empty potato chip bag.

And, the freewheeling prop is rotating "backwards" relative to the prop on the carts with the drive wheel connection.

I look forward to the journal article explaining the science behind that mystery.

Would my thing move into the wind, I don't know.

I hope you're kidding. I thought your rigorous scientific testing just proved otherwise for you. Or do you want to just keep repeating the experiment until the cart decides to spontaneously go into the wind?

 

[jduffy77]

When a tyre is on the road and does not slip, the tangential speed of the tyre at the surface, is the same as the road. That is, one meter or tyre, results in 1m of forward motion. The TM breaks that rule, and the only way it can do that is if it slips.

This is complete nonsense. The TM doesn't break any rule. The tires behave identically. Or are you wasting time talking about before the cart is at belt speed again?

 

[A.T.]

I'll just accept the configurations that work as proving the principle.

I don't quite see what principle they prove, that actually needed to be proven.