I found a graphic for you Humber, if you are really interested in educating yourself. I know you like graphics.
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Merged DDWFTTW in a “Real” Wind
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I found a graphic for you Humber, if you are really interested in educating yourself. I know you like graphics.
It looks like it is.
That does not help in the least. Your own diagram shows that a tailwind will produce a turbine torque. The video says it does, and that the prop is all but useless. 3W. I keep telling you 3W at 15rpm. That will not go away.
It's about as bad a design as is possible. Selected for "efficiency" by plugging in numbers into an internet calculator. Caveat Emptor.
The prop needs an engine to drive it the other way. The diagram assumes that you understand that. That is rather the difference between a wind turbine generator, and a plane's propeller and engine.
Carteers always forget the engine. Lucky for you that Boeing use math.
Having "used up" the wind, you will need to find something ( the equivalent of the motor) to drive the rotor the other way, and oppose that turbine force. And you can say "ground power" and I will add that to the brake-drive hall of fame. Gearing too
EHocking
Penultimate Amazing
That's exactly what frame of reference dictates.
There is little more to it than that. And it's the car that is moving, not the road.
The talk of absolute motion v relative motion is snake oil.
Visual impression is just that. Patterns could be painted on the road that would lend the impression that the road was moving fasterforwards than the car.
And it's hard to argue that the road moves under parts of tank tread. The part in contact with the ground, does not move relative to the ground. The tank moves over it. Got a GT for that?
Attachments
CORed
Penultimate Amazing
Clearly humber is not interested in educating himself, because he thinks he already know it all. No matter how many times it is explained to him, no matter how many experiments are done to show that it works, he will remain mired in his willful ignorance. The wheels of the cart drive the propeller. But humber "knows" this is impossible, the "carteers" are trying to scam humber, but he's too smart to be fooled. The spool being pulled by the string wound underneath it only "looks like" it's going faster than the hand, because humber knows it's impossible for it to actually be going faster than the hand. Anything humber doesn't understand (and that covers a whole lot of territory) is somehow faked.
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As I told you already you are wrong. Ask Yev.
The wheels turn the prop. I showed you the difference between a prop and a turbine.
The cart does not "use up" the wind. You are embarrassing yourself again.
EHocking
Penultimate Amazing
Not in relationship the to boy sitting in it. Otherwise he'd fall off the seat or be rammed through a front/rear window.
Only because you can't seem to grasp it.
As demonstrated by you inability to see that in the spool/paper example, from a point reference on the paper, the reel would move away, not the paper.
I have no idea what a GT is - unless you're talking about a Ford.
CORed
Penultimate Amazing
But the road and the bottom of the tread do move backwards from the frame of reference of the tank. Just like the road and the bottom of the wheel from the frame of reference of the car. It's not hard to argue that. It's just hard (impossible) for humber to understand.
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Make up your mind. Is it exactly like an upwind cart, or does it have a different gearing?
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Michael C
Graduate Poster
By a GT he certainly means a Galilean Transformation.
I thought he was talking about Godfrey Gumbs.
EHocking
Penultimate Amazing
Things I have learned today
1. It's impossible to walk along the road unless my shoes are slipping
2. Travelling over the ground is actually, physically, different from having the ground travel under me. I shall bear this in mind next time I step on+off the travelling walkway at the airport. Especially when I walk backwards on it, just to freak out the people walking on solid ground alongside (try it, while looking panicky
Really!)
3. This thread is getting very silly.
4. Creating parody threads over in 'community' is more worthwhile
1. It's impossible to walk along the road unless my shoes are slipping
2. Travelling over the ground is actually, physically, different from having the ground travel under me. I shall bear this in mind next time I step on+off the travelling walkway at the airport. Especially when I walk backwards on it, just to freak out the people walking on solid ground alongside (try it, while looking panicky
Really!)3. This thread is getting very silly.
4. Creating parody threads over in 'community' is more worthwhile
CORed
Penultimate Amazing
The cart has used up all the wind. The wind will never blow again. All those wind turbines all over the world are useless now. Those carteers are evil.
Yevgheni has never commented on it.
The video says 3W. Too bad.
Engines drive props. No engine.
What drives the wheel? From a standstill?
Spontaneous motion?
That was for your benefit. You know, "backwards" roads and so forth.
If the wind is driving the rotor CCW, that means you need something else[/I to drive it forwards, other than the wind on the rotor.
Jack by the hedge
Safely Ignored
A GT?
When the paper is rapidly jerked away, the cotton reel's inertia will dominate over its rolling resistance trying to make it go with the paper. Consequently most of the work done by the frictional force on the reel's rim spins the reel around its centre of gravity and only a tiny proportion accelerates the reel in the same direction as the paper.
Happy with that?
Why you consider this to be (as I surmise) a useful model of a cotton reel blown along by the wind, I cannot fathom.
No, the tank moves over the tread. In the same way a car moves over the road.
There is no significant motion between the tread and the road. The small boy standing on the tread may conclude that the tank is not moving, and for exactly the same reason that you think the road moves under the car.
The idea that the road moves under the car is indeed a boyish one.
Galileo was not concerned with how things looked. He talked of the motion of objects. Velocity was later coined by Newton.
Others before Galileo had experimented with mirrors and stuff to see how they influenced motion. Before optics, science had no explanation for vision.
Hobbes thought that something extended from the eye to make contact with the object. He realized that lenses and mirrors posed a problem
Thinking that the road moves under the car, is no less ridiculous. If you continue to follow Spork, it won't be long before you are building a new Stonehenge.
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But if you pull slowly it stays in place. You can do exactly the same with a simple toy car. Try it. It will drift back a bit.
That leaves you to explain how much of a difference could there be between that, and not moving back at all, and WTF does that have to do with windspeed travel?
ETA:
You are almost right. Most of the gimmick is that the expected linear motion - being pulled back- becomes angular motion as the wheels turn. Spin. Not roll up the belt.
The rest, including the prop is a matter of engineering the solution, but Spork arrived at it by trial and error and thought he had found gold.
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Jack by the hedge
Safely Ignored
The "tacking prop idea" is a helpful analogy for sailors. The propeller isn't doing anything exotic or unusual. It's just doing what propellers do. The analogy of the moving blade to a tacking sail is revealing (to those more familiar with the latter), simple and accurate.
I suspect you haven't checked them all yet. You may find someone's made the analogy before or you may not. I'm not that bothered, personally, but do let us know if you happen to find it in print.
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