Down wind faster than the wind

[spork]

...humber "pressed my buttons" by posting a link to lecture notes by a friend and colleague of mine (Prof. Drela). These notes do not at all support humber's position

For those not familiar with Mark Drela ( http://web.mit.edu/aeroastro/people/drela.html ) he's a bit of a legend in the field. To see his name in the same sentence with humbers is a bit painful.

I'f you'd be willing, humber, I'll engage you in a dialogue here in which I will explain how a cart like the one in the videos can go DDWFTTW.

I'll watch and be entertained. I'll even admit that if anyone can do it, you probably can. But I'll warn you ahead of time - no one can. In fact I'm absolutely 100% positive that humber can't and/or won't understand and accept this for what it is - and no one will ever be able to change that (I doubt even humber will fall for my cheap attempt at reverse psychology - but here's hoping he decides to prove me wrong).

 

[jjcote]

I'm surprised, spork. I expected that your reaction would be more like, "humber can't be persuaded -- if you think you can do it, I'll bet you $100,000 that you can't, and I'm certain that I won't lose". That would be in character for you. And there's no way I'd take you up on a bet like that.

 

[spork]

I'm surprised, spork. I expected that your reaction would be more like, "humber can't be persuaded -- if you think you can do it, I'll bet you $100,000 that you can't, and I'm certain that I won't lose". That would be in character for you. And there's no way I'd take you up on a bet like that.

You misunderstand my character. I don't gamble. I'd be happy to bet $100K on a sure thing (as I have many times), but to bet that humber won't agree with your definition would be silly. The man is a random process.

Also, I only offer the bet to people that are just 100% sure I'm wrong. I don't think you hold that position.

I assume I've offended you somehow?

 

[jjcote]

No, no offense. I'm just facetiously suggesting that the impossibility of educating humber is nearly a sure thing. And I wouldn't bet that it isn't.

 

[humber]

Examiner: So, Mr Humber, as I showed you, increase the gas and gently let out the clutch pedal. Get the balance wrong one way, we'll roll back down the hill, the other, and we'll move off up the hilll. That's it: you've got them nicely balanced now. Feel that, how we're just hovering?
Humber: Jesus, you mean I'm flying this thing already?

If a change in nomenclature, the use of an other metaphor, confounds you, then perhaps you should return to the gee-I-don't-know ingénue of your earlier posts.

 

[humber]

Where was I? Oh yeah, I was commenting on this thread when I suddenly learned a lot about power and energy loss the hard way. The ice storm knocked out the electricity in my town, it took NINE DAYS for the power company to get me back on line, and in the meantime I had to deal with temperatures dropping to 10 F and making sure that my house didn't freeze.

Anyway...

Breathlessly, I wait.

I'm inclined to just continue sitting back to watch this semi-entertaining bunch of words bounce back and forth, but humber "pressed my buttons" by posting a link to lecture notes by a friend and colleague of mine (Prof. Drela). These notes do not at all support humber's position, but it's annoying to see Drela's work being waved around ostensibly in support of a fallacy.

The only notes I posted to where in connection with electrical analogues, propellors and motors. I say that is useful to the understanding of the problem. If this "pushes your buttons", the your response is going to have to be more substantial than I am misrepresentation Prof Drela. See if you can do that using your own wits. By the way, your attempts at lofty superiority are embarrassing.

I'm interested in educating the recalcitrant, and we have a clear example here. I'f you'd be willing, humber, I'll engage you in a dialogue here in which I will explain how a cart like the one in the videos can go DDWFTTW. I recognize that your grasp of physics does not allow you to understand how the treadmill test is a direct, excellent demonstration of this, so the dialog will stay away from the treadmill example and deal only with carts moving relative to some big parcel of dirt
At the end of this dialog, I believe* that you will agree that such a cart can work. I don't have any hope right now of getting you to understand that the one in the videos is actually doing so, and you'll be welcome to believe that although it can easily be done, spork et al are committing a fraud**, and their cart isn't actually doing it.

Shall we begin?

No, you go ahead on your own - your are doing fine. Even the most obtuse mind would realise that I am discrediting the treadmill, Spork's credibility, and the frames concept.
So, firstly to save you the time, I will post some unequivocally clear drawings that will demonstrate that you are wrong about the role of the treadmill.
When that is done. I will show you how to make a generic windcart, that under your rules, will always be seen as faster than the wind.

(In case you didn't pick up on it, I insulted you several times in the paragraphs above. I would have opened with the traditional "With all due respect...", but I'm already providing more than that.)

Yes, heavy-handed irony. Spork cannot even compliment his friend, JB, without casting himself in an even brighter light. You are similar. You make engraved remarks, and then point to them, just in case I missed how clever you are.

*Who am I kidding? Why do I think I can succeed where so many others have failed? What I actually believe is that I'll be faced with a bunch of words from you than have some degrees of syntax, but nothing to redcommend them in the way of semantics.

You just told yourself the answer. Don't stray from the shallow end on that last topic...

**There is a major fraud being committed in the videos, by the way, that is clear. It has already been admitted elsewhere that the white plastic thing is not actually a spork.

Inane.

 

[humber]

For those not familiar with Mark Drela ( http://web.mit.edu/aeroastro/people/drela.html ) he's a bit of a legend in the field. To see his name in the same sentence with humbers is a bit painful.

Ask him if he agrees with you. <snip>

JJcote:
I have looked in my bookmarks. There are no Drela references. The prop. article bears no author. Unless you can show me that I have misrepresented Prof Drela, you owe me an apology.

 

[humber]

Dan's absolutely right of course. But I'd like to clarify that Q factor hasn't got a thing to do with the DDWFTTW cart anymore than "hopping" or "hovering" does (a fact that I'm quite certain Dan understands).

While I think everone but humber understands the following point, I guess it bears mentioning anyway. When I mention that JB has the cart "hovering" on the treadmill, I'm using the term in the 2-dimensional sense. In other words JB has the speed and incline of the treadmill balanced carefully enough that for the moment the cart is neither advancing nor retreating. As you can imagine, the cart is neutrally stable in this configuration (it has no specific tendency to hold its postion, nor does it have a direct tendency to diverge from that position). This particular video was made in response to a skeptic that wanted to see the cart hold position on the treadmill for a longer period of time unnaided. Somehow humber feels the fact that we were able to manage that precarious balance for a little under two minutes proves his bizarre "theory" of operation.

Good, keep digging yourself in. The more hyperbolic you are, the louder the crash when grounded. Q has a place in the treadmill system. Nothing for you to think about, though.
This time, when I post a rebuttal of your ideas, as promised JJcote, stick around. Don't let poor JB fight your corner.

 

[John Freestone]

Q factor^WP is a term used in electronics to describe the quality of a tuned circuit. Q is computed as the ratio of the reactance to the resistance. To translate this to a mechanical system (say a pendulum), Q would be a ratio between the mass of the pendulum to the loss due to friction.

Dan's absolutely right of course. But I'd like to clarify that Q factor hasn't got a thing to do with the DDWFTTW cart anymore than "hopping" or "hovering" does (a fact that I'm quite certain Dan understands).

While I think everone but humber understands the following point, I guess it bears mentioning anyway. When I mention that JB has the cart "hovering" on the treadmill, I'm using the term in the 2-dimensional sense. In other words JB has the speed and incline of the treadmill balanced carefully enough that for the moment the cart is neither advancing nor retreating. As you can imagine, the cart is neutrally stable in this configuration (it has no specific tendency to hold its postion, nor does it have a direct tendency to diverge from that position). This particular video was made in response to a skeptic that wanted to see the cart hold position on the treadmill for a longer period of time unnaided. Somehow humber feels the fact that we were able to manage that precarious balance for a little under two minutes proves his bizarre "theory" of operation.

Well there's a surprise! Thank you anyway.

I'f you'd be willing, humber, I'll engage you in a dialogue here

Good luck. (I know, spork beat me to it)

At the end of this dialog, I believe* that you will agree that such a cart can work.

That's one problem there. I think he said so himself. He could make one that worked, obviously. But no-one else's attempts to demonstrate one working are acceptable. Something like that.

I don't have any hope right now of getting you to understand that the one in the videos is actually doing so, and you'll be welcome to believe that although it can easily be done, spork et al are committing a fraud**, and their cart isn't actually doing it.

...or, as I keep saying, he does believe it by now, but someone told him you should always stick to your guns.

If a change in nomenclature, the use of an other metaphor, confounds you, then perhaps you should return to the gee-I-don't-know ingénue of your earlier posts.

Float here and say that. "Ingénue" - priceless! Humber calls me a liar, and in French.

 

[jjcote]

By the way, your attempts at lofty superiority are embarrassing.

Well, I don't feel embarrassed. Perhaps I'm embarrassing somebody else.

your response is going to have to be more substantial than I am misrepresentation Prof Drela

I didn't say that you misrepresented Prof. Drela, I said that you pointed to his lecture notes (yes, they are his) in support of your assertions, which are not accurate.

See if you can do that using your own wits.

Ask him if he agrees with you.

Contradictory advice, but I'll opt for the former. Mark and I have been friends since we were undergraduates together, and there's no need for me to bother him with something that I'm fully capable of explaining myself. I don't need to check with him on this any more than I'd have to ask him about any other simple physics problem. (I would contact him if, for example, I needed an efficient propeller design, though.)

I will show you how to make a generic windcart, that under your rules, will always be seen as faster than the wind.

It could be that I don't completely understand your position, since you refer to "your rules" (meaning, I presume, "jjcote's rules") despite the fact that I haven't stated any rules that I'm aware of. Maybe you accept DDWFTTW, but just not the treadmill demonstration? In any case, I can remedy this by putting forward a set of rules.

Given:
1) A flat, level area on the surface of the earth, that is conducive to traction with wheels
2) A uniform air mass moving at a constant speed and direction across that area
3) A cart with non-slipping wheels on the surface, a propeller in the air mass, high enough that it is in the uniformly moving air and away from the boundary layer near the surface where the air will be moving more slowly, and a fixed-ratio transmission connecting the wheels to the propeller
Then:
It is possible for the cart to move, steady-state, with no external power source available other than the "wind" (i.e. the air moving relative to the surface) in a direction identical to the "wind", at a speed that is greater than the "wind". That is, if the air is moving at a speed of e.g. 10 mph, the cart will move at e.g. 12 mph.

Do you agree or disagree that this is possible, or are there any additional clarifications that you think need to be put in place?

 

[humber]

Float here and say that. "Ingénue" - priceless! Humber calls me a liar, and in French.

SOED:
ingénue /anZeI"nju:; foreign EZeny (pl. same)/ n. Also -gen-.M19. [Fr., fem. of ingénu INGENUOUS.]

An artless innocent young woman, esp. as a stage role; an actress playing such a role.

 

[humber]

Well, I don't feel embarrassed. Perhaps I'm embarrassing somebody else.

I'll hide my blushes. If you want to play against personalities, expect return fire.

I didn't say that you misrepresented Prof. Drela, I said that you pointed to his lecture notes (yes, they are his) in support of your assertions, which are not accurate.

You wrote;

I'm inclined to just continue sitting back to watch this semi-entertaining bunch of words bounce back and forth, but humber "pressed my buttons" by posting a link to lecture notes by a friend and colleague of mine (Prof. Drela). These notes do not at all support humber's position, but it's annoying to see Drela's work being waved around ostensibly in support of a fallacy

You most certainly did.
Also, if you do keep in contact with Prof Drela, perhaps you could ask him if he agrees with Spork's ideas, otherwise, I would suggest that you are representing him without his authority.

Contradictory advice, but I'll opt for the former. Mark and I have been friends since we were undergraduates together, and there's no need for me to bother him with something that I'm fully capable of explaining myself. I don't need to check with him on this any more than I'd have to ask him about any other simple physics problem. (I would contact him if, for example, I needed an efficient propeller design, though.)

What makes you think I do?
OK, do so, on your own.
I say to you again, this is about the treadmill. The logic and design behind it.
You can't Wikki that, or 'phone a friend'.

It could be that I don't completely understand your position, since you refer to "your rules" (meaning, I presume, "jjcote's rules") despite the fact that I haven't stated any rules that I'm aware of. Maybe you accept DDWFTTW, but just not the treadmill demonstration? In any case, I can remedy this by putting forward a set of rules.

The normal accepted means of this forum. It "looks like it does", socks in the air, standard wind measurements.

Given:
1) A flat, level area on the surface of the earth, that is conducive to traction with wheels

Yes, OK.

2) A uniform air mass moving at a constant speed and direction across that area

The cart has not been demonstrated to do that. So, windspeed means natural wind. Still possible under the later, though.

3) A cart with non-slipping wheels on the surface, a propeller in the air mass, high enough that it is in the uniformly moving air and away from the boundary layer near the surface where the air will be moving more slowly, and a fixed-ratio transmission connecting the wheels to the propeller

Yes. do yo uhave evidence that the wheels are not slipping? Anyway, that concerns the engineering that is employed to achieve the desired outcome.
I can stick with that, or propose my own.

Then:
It is possible for the cart to move, steady-state, with no external power source available other than the "wind" (i.e. the air moving relative to the surface) in a direction identical to the "wind", at a speed that is greater than the "wind". That is, if the air is moving at a speed of e.g. 10 mph, the cart will move at e.g. 12 mph.

You have no evidence that has been achieved. As I said, I will present a generic cart that works under those conditions. You would have to deny me that it cannot be modifed or extended to meet other conditions.
Details regarding the wheels, are one of many methods that could be employed, but not necessary to the principle of operation.
"Steady State" is meaningless. I would say that the cart must have no other source of energy than is what is immediately available to it from the wind.

Again, treadmill first.

Do you agree or disagree that this is possible, or are there any additional clarifications that you think need to be put in place?

1) Goodman's cart explicable under the presented conditions.
2) Spork's cart also, but that is operation slightly different because of its low mass and small size. There are perhaps tertiary effects in this case.
3) Ventomobile is a science project. They measure the energy taken from the wind, and the amount transferred to the cart. They ( I presume) calculate from logged data, the vehicle's efficiency. Under those conditions, a DDWFTTW is not possible.

 

[jjcote]

1) I am not representing Mark Drela without his authority. On the contrary, I am leaving him out of it. I will say that those lecture notes, while quite valid, don't have much relevance to this particular discussion.

2)

Yes. do yo uhave evidence that the wheels are not slipping?

For the purposes of discussion, I'm happy to discuss a vehicle running on a toothed track, with toothed wheels, which would simultaneously enforce the direction of the vehicle and ensure that there's no slipping. Not that I think there's any problem with slipping wheels. If a vehicle travels DDWFTTW with the wheels slipping, it's still going DDWFTTW.

3)

You have no evidence that has been achieved. As I said, I will present a generic cart that works under those conditions. You would have to deny me that it cannot be modifed or extended to meet other conditions.

I didn't say that I would present evidence that it has been achieved. I said that I could explain why it is possible. I guess you're saying that you agree that it is.

4)

"Steady State" is meaningless. I would say that the cart must have no other source of energy than is what is immediately available to it from the wind.

I'm trying to decide whether your statement is more vague than mine. By "steady state", I mean that it is in a condition where the velocity of the cart, the rotational speeds of all parts, etc. are not changing. In your statement, based on what you have said before, I'm not sure what you would count as an "other source of energy". Given that it will have rotating wheels, there will be some kinetic energy stored in those wheels. Since we can't make massless wheels, would that be a problem?

5)

Again, treadmill first.

Read what I wrote again. I am not (at this time, anyway) offering to discuss the operation of the cart on the treadmill. I am offering to discuss the operation of a cart such as this on a flat, smooth piece of ground with the air moving past the ground.

6)

Do you agree or disagree that this is possible, or are there any additional clarifications that you think need to be put in place?

1) Goodman's cart explicable under the presented conditions.
2) Spork's cart also, but that is operation slightly different because of its low mass and small size. There are perhaps tertiary effects in this case.
3) Ventomobile is a science project. They measure the energy taken from the wind, and the amount transferred to the cart. They ( I presume) calculate from logged data, the vehicle's efficiency. Under those conditions, a DDWFTTW is not possible.

I've read this several times, and I can't figure out what you're trying to say. Are you saying that Goodman's cart works, the spork/JB cart also works, and that a vehicle like Ventomobile can't work because of something that they're doing pertaining to measurement?

If you are taking the position that DDWFTTW actually does (or at least, actually can) work, then we're in agreement on this point and don't need to discuss it. (If that's the case, then I may address the treadmill issue, but I want to know where we stand on the main issue first.)

 

[spork]

By the way, your attempts at lofty superiority are embarrassing.

I don't think JJ is "attempting" anything. His intellect simply IS superior to yours. It's too bad that embarrasses you.

When that is done. I will show you how to make a generic windcart, that under your rules, will always be seen as faster than the wind.

I don't have the first clue as to what you hope or plan to show us, but I have two predictions that I'm fairly certain of:

1) You will never produce any drawings or descriptions of any kind. You simply don't have the necessary attention span. I suspect you already wonder what we're talking about.

2) In the extremely remote case you do provide such plans or description, I'm quite confident your cart won't be capable of doing whatever you claim it can.

Spork cannot even compliment his friend, JB, without casting himself in an even brighter light.

I think I've given JB plenty of compliments with no reference whatever to me or anyone else. He's been a good friend for many years, and is a very sharp guy.

JJ, good luck with humber. He is to be used strictly for entertainment purposes. Anything else falls outside of warranty.

 

[spork]

If you are taking the position that DDWFTTW actually does (or at least, actually can) work, then we're in agreement on this point and don't need to discuss it. (If that's the case, then I may address the treadmill issue, but I want to know where we stand on the main issue first.)

JJ,

Your approach is perfectly logical and reasonable - assuming you were talking to a sentient being. Prepare to be frustrated.

 

[Christian Klippel]

JJ, good luck with humber. He is to be used strictly for entertainment purposes. Anything else falls outside of warranty.

I always thought that broken surplus stuff comes without any warranty at all....

 

[jjcote]

The only positive trait that I credit myself with is patience. Perhaps I'll be frustrated, but I'm willing to try for a while, if humber is interested in having the discussion.

 

[Thabiguy]

Btw, spork...

How's the MythBusters episode coming along? Here and there I catch a remark hinting that it is on a good way, but haven't seen anything specific (or maybe there was something but I overlooked it). Did they agree to do it, or is that yet to happen? What's the story? (Unless it's for some reason confidential, of course.)

 

[spork]

...I'm willing to try for a while, if humber is interested in having the discussion.

But that's where he gets you. He's definitely interested in the discussion. He's just not willing to allow it to reach any conlcusions of even the smallest sort. Nor will any of his posts be responsive in any meaningful way.

I'm not sure why we continue to toy with him ourselves; probably just because he's so completely condescending in his wrongness.

 

[spork]

Btw, spork...

How's the MythBusters episode coming along? Here and there I catch a remark hinting that it is on a good way, but haven't seen anything specific (or maybe there was something but I overlooked it). Did they agree to do it, or is that yet to happen? What's the story? (Unless it's for some reason confidential, of course.)

Nothing confidential about it. Unfortunately I probably haven't heard much that you haven't. Mark Frauenfelder of Make Magazine apparently emailed Adam and got back the word that the idea is "in the hopper". More recently Mark said he'd be seeing Adam next month and would mention it to him personally.

Meanwhile I've made a DDWFTTW cart for Mark, and will be shipping it today. I'm still hoping he'll allow me to write the follow up article for Make Magazine.