RAI
Well-Known Member
Yes the propeller is driven by or drives the wheels. There is a link to an article about it just below the video.
Sailing downwind - faster than the wind?
- Thread starter Pierrome
- Start date
fireball
Well-Known Member
Hmm - interesting query - it would be nice to see a tell tail in the props airflow as well as the one to the side.
HoratioHB
Well-Known Member
In which case my question stands, the cart moves off with the wind from astern, rotating the prop anticlockwise, then the wind moves ahead as the cart accelerates but the prop clearly cannot reverse direction!!!!
Ubergeekian
Well-Known Member
It reverses effect, and starts pulling the cart through the air, driven by the road wheels.
Pierrome
Well-Known Member
Maybe you don't understand that the prop is driving the cart through the air. It's not a windmill.
This is exactly the same as when a propeller plane starts its takeoff run with the wind behind it. It soon catches up with the wind and exceeds it.
pmagowan
Well-Known Member
This idea of 'relative' is just wrong. The driving force is the wind, not the road. The wind pushes something forward and it moves along the road. This creates other forces such as friction which turns the wheels. The wheels can not then power the craft as their forces are a direct result of the original force of the wind and therefore can not be larger than it. The wheels can only slow the craft down, not speed it up. What you are alluding to is a feedback mechanism where the feedback is greater than the original force. This breaks the laws of thermodynamics as energy can not be created.
As I said, any apparent pepetual motion machine is just gaining force from somewhere the originators have not forseen or the originators are trying to trick you. In this instance the only ways I can think of are, going down a hill and poor measurement of true wind speed and vehicle speed.
As I said, any apparent pepetual motion machine is just gaining force from somewhere the originators have not forseen or the originators are trying to trick you. In this instance the only ways I can think of are, going down a hill and poor measurement of true wind speed and vehicle speed.
Lady Campanula
N/A
Well, this intriguing topic has kept the good burghers of the AYRS going for close on 20 years. And while some of 'em are certainly 'barking', closed minds they ain't got.
So, good forumeers, since this will injure neither your pride nor your pocket, open your minds, have a peek at the vids, and have a pensive 'what if.....'
They said much the same about 'heavier-then-air flight', 'the earth moves around the sun', and 'the earth is flat; just look at it.....!'
So, good forumeers, since this will injure neither your pride nor your pocket, open your minds, have a peek at the vids, and have a pensive 'what if.....'
They said much the same about 'heavier-then-air flight', 'the earth moves around the sun', and 'the earth is flat; just look at it.....!'
Pierrome
Well-Known Member
"Relative" is correct. So are you saying that a moving surface (such as a conveyor belt or a walking treadmill) and stationary air, is not the same as a stationary surface and moving air (wind)? If so, that is wrong.
Because if you claim that, then such a thing as (for instance) a wind-tunnel test cannot be valid because the plane tested is stationary and the air moving, which is the opposite of what happens in real life. Then all the aircraft engineers throughout history must be wrong!
BTW please check out the second video that was mentioned earlier - which involves the use of a treadmill.
colingr
Well-Known Member
Ubergeekian
Well-Known Member
You are confusing energy and force.
AntarcticPilot
Well-Known Member
Well, this intriguing topic has kept the good burghers of the AYRS going for close on 20 years. And while some of 'em are certainly 'barking', closed minds they ain't got.
So, good forumeers, since this will injure neither your pride nor your pocket, open your minds, have a peek at the vids, and have a pensive 'what if.....'
They said much the same about 'heavier-then-air flight', 'the earth moves around the sun', and 'the earth is flat; just look at it.....!'
Unfortunately, this is effectively (though not obviously) a perpetual motion machine, and as such is attempting to break some of the fundamental laws of the Universe - the Laws of Thermodynamics. As these laws are not merely empirical observations but can be derived by analysis of physical systems, we would have to be SO wrong in our understanding of the physical universe that it is doubtful if boats should float, if a perpetual motion machine was shown to exist.
The examples you give are cases either of incorrect interpretations of existing physics (heavier than air flight) or incorrect interpretation of observations. Note that the "heavier than air" thing is also quoted out of context - I have yet to see a lighter than air bird! The context was that a heavier than air flying machine would be unable to carry a useful payload - a reasonable observation at the time, given the low power density available from engines at the time.
bbg
Well-Known Member
If this system works, it should work at all windspeeds, no? So if True Wind Speed = 10 knots, it should be able to go downwind at something over 10 knots?
Or if TWS = 0* it should still be able to move downwind i.e. in any direction. There are a lot of sailors who would LOVE to be able to sail at a useful speed in a flat calm.
*0 is, coincidentally, the percentage chance that this thing will do what it is advertised to do.
Or if TWS = 0* it should still be able to move downwind i.e. in any direction. There are a lot of sailors who would LOVE to be able to sail at a useful speed in a flat calm.
*0 is, coincidentally, the percentage chance that this thing will do what it is advertised to do.
Pierrome
Well-Known Member
This has now been proven many times, and as mentioned earlier - the "man carrying version" is nearly ready to be tested.
If you don't believe it, you need to explain how what you see in the videos is not what it appears.
bbg
Well-Known Member
I can't watch the videos from my current location, so perhaps you could explain to me: What is the energy source and energy transfer mechanism for the movement? I imagine your device (I've seen the photos) on the Bonneville salt flats on a perfectly calm day. Does it just begin to move (in any direction you point it)? If so, how?
Edit - and I think it is actually up to you to explain how the system works, not for others to debunk it. I can, even without watching a video, imagine that the appearance of travelling faster than the wind could be generated through short-term effects (e.g. gusts increasing the speed of the vehicle, then momentum carrying it faster than the wind for a period of time) and choices of measurement location (there will be a measurable difference in wind speed at ground level compared with 5 m and 10 m; the vehicle itself will influence the measurements).
Edit - and I think it is actually up to you to explain how the system works, not for others to debunk it. I can, even without watching a video, imagine that the appearance of travelling faster than the wind could be generated through short-term effects (e.g. gusts increasing the speed of the vehicle, then momentum carrying it faster than the wind for a period of time) and choices of measurement location (there will be a measurable difference in wind speed at ground level compared with 5 m and 10 m; the vehicle itself will influence the measurements).
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fireball
Well-Known Member
Ok .... so look down from above the Prop and the top half has a / appearance ...
so - wind passes that and the / will move to the left (or anticlockwise) ... and the craft will move UP ...
for the / to turn at a rate where the air is passing the other way and the Prop to be providing thrust against the air either the prop has to turn clockwise or the craft has to move DOWN ...
I'm ignoring anything about how or why the prop can move faster - but just looking at the effect of the prop itself ...
Malo37
Well-Known Member
With the greatest respect, this is nonsense. You can find video's on utube of pigs flying etc and there is no requirement to explain why that is not possible to vindicate the basic laws of mechanics as per Newton. This is a " prove god doesn't exist" kind of logic. As several posters have pointed out if there is no apparent wind there is no energy available to be collected from the wind therefore no resultant force. Pretty basic really.
Pierrome
Well-Known Member
You need to think deeper about this!
Read this carefully.
So you are saying that something travelling at the same speed as the wind (no apparent wind) cannot collect energy.
Consider then a balloon travelling with the wind about 20ft above the sea. There is no apparent wind to anyone in the balloon, but the sea appears to be moving underneath.
The balloonists then lower a water turbine into the sea. Can they get power from it? Yes, of course they can! because there is relative movement between the balloon and the sea.
So it is with the downwind cart. The cart is only supported on wheels, but it is moving at the same speed as the wind, and can (in the same way as the balloonists) obtain energy from the moving road.
We know that a wind-turbine powered boat can go directly into the wind, driven by the wind through the water.
So therefore, there is no reason why this cannot be reversed and a craft driven through the wind by the water, or land in the case of the downwind cart.
wingsailor
New Member
That's certainly true. I have been working on wind-turbine powered boats for years and there are always a certain amount of people who insist that it is "impossible" to make a wind powered boat that sails directly into the wind even if they see it on youtube (which you can) just search under "windmill driven boat".
I even had to design a simple model to prove the principle which can be found on http://www.sailwings.net/windspinner.html
Malo37
Well-Known Member
But read this carefully
If the balloon lowered a water turbine into the sea, the drag of such turbine would cause the balloon to slow down with respect to the wind - there is no other possible outcome. Consequently the baloon would then be travelling slower than the wind ergo - it is not travelling faster than the wind.
If the balloon lowered a water turbine into the sea, the drag of such turbine would cause the balloon to slow down with respect to the wind - there is no other possible outcome. Consequently the baloon would then be travelling slower than the wind ergo - it is not travelling faster than the wind.
bbg
Well-Known Member
But under your example, lowering the water turbine into the sea would slow the balloon down (drag on the water turbine), and now the balloon would not be travelling as fast as the wind. The energy derived from the turbine could be used to power a propellor on the balloon, thus driving it forward, but the losses in the system will mean that the propellor will produce less thrust than the drag caused by the water turbine. So the balloon will still be travelling slower than the wind.
By all means continue your experiments, but you will never achieve what you say you want to achieve. Never.