Going against the wind I cannot see that any physical law is infringed if you go faster than the negative speed of the wind. It just depends on the ratio of drag force to the force possible from the energy generated from the turbine.
Going with the wind however is still difficult to grasp for me, especially with a number of contradicting explanations.
Sorry I don't get the three point thing. So I made my own theory.
I assume an ideal friction less vehicle, a propeller that has nearly as much uplift as drag.
So I can assume if the propeller is not connected to the wheels, that the vehicle runs nearly at wind speed. I understand that energy can be 'harvested' from the wheels by e.g. attaching a generator. This slows the vehicle down by say 10%. The generated energy can be invested into forward drive to speed the thing up. Maybe even a it faster than the wind. Wow! Now we can harvest even more energy from the wheels! And using the energy we can go even faster. By repeating this the vehicle gets faster and faster and faster. As everything is ideal, we might even go beyond light speed. Bad luck, thanks to Einstein the vehicle is getting to heavy. When we reach 80% of the speed of light it is so heavy that the bearings begin to glow and set the car on fire. And this brings me back to earth...
I was nearly there by using Muechhausen's trick. This is the story of a German guy who pulled himself out of a swamp by pulling his hair up as hard as he could.
Well I could not convince myself yet but I am still chewing on it.
sun2steam said:
As everything is ideal, we might even beyond light speed.
Assuming 100% efficiency there is no upper bound on the achievable wind-speed multiple. The same applies to the gear-carts shown in the video. Given proper gearing, traction and material strength they can go 10 times faster than the paper that drives them, or more.
Of course there are limits on the absolute speed like light speed. But in practice even the speed of sound would be hard to break, because the efficiency of the propeller goes down.
The rapid and flat twist of the wrist as it is thrown is surely the secret as the incredible (world record) distances are not achievable without this readily described necessary action.
We know that rotation stabilises other motion and that the X-Zylo's flight is gyroscopic by nature (and necessity).
We also know that a plane's wing in flight has a surface layer of air that barely moves.
We also know that with increased velocity, air increases in volume and correspondingly becomes lighter by mass.
We also know that toroidal vortices can travel long distances at varying speeds, dependant on the impact generated velocity.
My theory is that the twisting motion when thrown generates a thin gyroscopic layer of air around both sides of the wall. This would allow the X-Zylo to slice through the air without disturbing the gyroscopic boundary air layers which simply remain adhered to the rotating wall.
While the rotating boundary air layers would not form toroidal vortices, they would nevertheless have the same dynamics (apart from not rotating in on themselves) and would therefore serve as lighter than air propulsors with the same momental characteristics as toroidal vortices to carry the way.
“ If everyone is thinking alike, then no one is thinking. ”
As food for thought from "left-field", here is an electrostatic hypothesis.
The faster the rotation of the X-Zylo the higher is the speed of the air relative to the device.
The higher the relative air-speed, the larger is the number of coulombs of negative electrostatic charge that accumulate on the device.
The larger the negative charge on any device within the earth's electrostatic field
( of about 100 volts per vertical metre ),
the larger is the electrostatic force on that device.
Can anyone help with the equations for calculating
(1) the number of coulombs and
(2) the size of the electrostatic force ?
Another thought-provoking experiment is to suspend a table-tennis ball by using the air that is flowing out from a hose that is attached to the exhaust-outlet of a vacuum cleaner.
Sailing faster than the wind can be traced back to the early 1970s and the iconic 18 foot skiff.
In 1972 at the world championships (the JJ Giltinan trophy) in Brisbane, Don Lidgard from NZ used a flat cut asymmetrical spinnaker to tack downwind. Up until then everyone thought that to go faster downwind you just needed to set larger and larger sails. In fact legend has it that when the boats rounded the top mark and set their spinnakers for the square run downwind, they saw the Kiwi boat head off at an angle, so they thought it was retiring from the race, imagine their surprise when Lidgard gybed over onto another tack and swooped into the bottom mark in front of all the square running boats!
Thus was born the art of tacking downwind and sailing faster then the wind when sailing downwind. What they were doing was using the boats forward speed to increase air flow over the sails, and to get the boat to plane across the water, so although they were sailing a longer distance, they were doing so at much greater speed. No high performance sailing boat ever since sails square downwind any more.
Russell Moore said:
Sailing faster than the wind can be traced back to the early 1970s and the iconic 18 foot skiff.
Yes, conventional sail-craft, which tack across the wind, can do it for a while. In fact iceboats did it over 100 years ago. The currently fastest wind powered vehicle went 126mph in 30-40mph wind:
On water the record was broken just a week ago (not official yet) with 75mph in 30mph wind:
The rotor vehicles that go parallel to the wind faster than wind are working on the same principle:
" According to Coulomb's Law, two point charges of +1 Coulomb, placed one meter apart, would experience a repulsive force of 9×10^9 Newton, a force roughly equal to the weight of 920,000 metric tons of mass on the surface of the Earth."
and
" One coulomb is the magnitude (absolute value) of electrical charge in 6.24150965(16)×1018 protons or electrons."
" If a powder, such as sugar or flour, slides down a tube and sticks to the wall, the charge on each tiny particle could be 10–14 to 10–13 C, i.e., 100,000 to 1 million electrons have been transferred per particle. A person who has walked across a carpeted floor receives a shock when touching a doorknob that typically has a charge of about 10–7 C. Powder sliding down a tube often has a specific charge of about 10–7 C•kg–1. A plastic folder rubbed with a piece of cloth or fur typically produces a charge of 10–7 C per sheet."
also
" The charging observed with ordinary compressed air is caused by liquid or solid impurities of the gas impinging on the target and, therefore, is a case of dust charging rather than gas charging. The polarity of the target charge can be either positive or negative, depending on the nature of the target as well as that of the impurities."
" Static electricity is created by movement between non-conducting materials. In fans, this may even occur due to friction between an impeller blade and air molecules.
While this is not a problem with metal blades, static electricity can build up sufficiently in fans with plastic blades to create a charge. "
TonyT
Pick up a electronics theory book in your local science library. The first chapter will explain the difference between static and current electricity, and then say that static electricity is useless, nuisance, side effect, and carries on in chapter 2 with nothing but "current" electricity not "static". I believe that static electricity is one of the most ill researched and understood natural phenomena in the science world today. Just have a look at transverse and longitudinal wave propagation theory for antennas. Mobile phone antennas are not designed by calculation (just like airfoils) they are designed by experimentation. Any decent mobile phone antenna is "sculptured" or etched for each device. As below:
Another interesting item is that a golf ball will travel further on the earth through the resistance of the atmosphere, than on the moon through a vacuum, if both had the same specific gravity. This is because the golf ball "flies" through the air on earth but can't "fly" due to the lack of a medium on the moon. Try throwing a paper aircraft in a vacuum but with gravity, or landing an aircraft without air that creates lift against gravity.
------------------------------------------
S2s
On three ref. points: I found that the key on understanding the principles behind the DDW is to separate the individual components of the system. At first glance you might think you can see "all" of the mechanics at play, because it looks like a relatively simple machine. The problem arises out of the fact that the energy balance will only match the "video evidence" if the physics of each component of the systems and how it relates to another is understood. Like in the gearing examples from Krass, you need to see the individual components work and see the relationships of table, moving paper(wind), vehicles, gearing and even reference points of the stuffed animals.
So in the case of the vehicle (or sail boat) travelling at velocity in a direction, it needs a certain amount of energy to do so, to overcome friction and drag etc. The propulsive force can come from a engine, a sail or it could be a electric motor running from the charge of a wind turbine. Lets call this energy 1.
We can also agree that a sailing boat can exceed the speed of the wind across the wind, due to it's "sweep" of the wind and angle of attack. We can also agree that a sail boat has very limited angles in which this can occur and therefore it's heading is typically more perpendicular to the direction of the wind, due to the angle of the forces involved. The energy gained from this "sweep" of the wind we will call energy 2.
Now a rotor (turbine/propeller), like in the sail boat example above, can "sweep" the wind and produce energy, if it is stationary, or even if it is in motion laterally (provided the turbine remains perpendicular to the wind). The energy gained by the sweep of the turbine we will call energy 3.
Remember the angle of the rotor blades through it's rotation around it's axis is perpendicular to the wind (so at 90 degrees like the ideal case for the sail boat as above), and the angle of attack or the rotor blades is a little less (like that of a full sail) so that the rotor blades are being accelerated by the wind around the rotor pivot. A sail boat moves horizontally across the wind, a rotor however circularly. Imagine a rotor as a sail boat zig-zaging across the wind without loosing momentum on the turns. (like the "wings" on my sailing hydrofoil concept on page 1 of this thread)
Like with the across the wind sail boat, the energy gained from the velocity of the wind is swept area of airfoil over time, or work (Fxd) over time = energy. Remember a rotor (or sail) that does not move or rotate will not do work and will only create a force.
So if energy 3 (rotor) is the same as energy 2 (sail boat tack) and exceeds energy 1 (vehicle drag) which is required to overcome the resistance of the vehicle, the vehicle will be propelled at x velocity. Lets not forget that a vehicle running with the wind will require less of energy 1 than if it were to run perpendicular or into the wind because of drag. This helps also.
On gearing: Imagine you had a wheel chair on a train that was propelled forwards by the speed of the train through gears. Will it move faster than the train? Likewise, the gearing between turbine speed and wheel speed always allows the ground to wind speed differential to be used as a source of energy. Stop the train the wheel chair stops too. No wind = no propulsion:
The DDW "leverage's" the energy of the wind. Hope this helps.
BTW I'd imagine that the bearings would melt way before reaching 80% of c (light speed) namely more around 0.0001% of c. That's still around 300m/s or 1080kmh.
On Baron Münchhausen, it was him and his horse out of the swamp by pulling his hair, to be precise.
It's funny that you bring him up here, because the Münchhausen trilemma is very befitting here: (and in many instances in our discussions S2S buddy!!)
Wiki:
"If we ask of any knowledge: "How do I know that it's true?", we may provide proof; yet that same question can be asked of the proof, and any subsequent proof. The Münchhausen Trilemma is that we have only three options when providing proof in this situation:
The circular argument, in which theory and proof support each other (i.e. we repeat ourselves at some point)
The regressive argument, in which each proof requires a further proof, ad infinitum (i.e. we just keep giving proofs, presumably forever)
The axiomatic argument, which rests on accepted precepts (i.e. we reach some bedrock assumption or certainty) (JB notes: also currently the only commonly form of "evidence" accepted in science aka peer reviewed "common sense")
The first two methods of reasoning are fundamentally weak, and because the Greek skeptics advocated deep questioning of all accepted values they refused to accept proofs of the third sort. The trilemma, then, is the decision among the three equally unsatisfying options.
In contemporary epistemology, advocates of coherentism are supposed to be accepting the "circular" horn of the trilemma; foundationalists are relying on the axiomatic argument. Views that accept the infinite regress are branded infinitism."
And
"This argument runs as follows: All of the only three ("tri"-lemma) possible attempts to get a certain justification must fail:
All justifications in pursuit of certain knowledge have also to justify the means of their justification and doing so they have to justify anew the means of their justification. Therefore there can be no end. We are faced with the hopeless situation of 'infinite regression'.
One can justify with a circular argument, but this sacrifices its validity.
One can stop at self-evidence or common sense or fundamental principles or speaking 'ex cathedra' or at any other evidence, but in doing so the intention to install certain justification is abandoned."
I'm wondering if I just gave my self away and the art in which I argue. Bummer!
Regards
JB
JB, you explained just nicely that science cannot 'proof' anything, but just give probabilities. I tried to explain that to you for a long time.
However it is much easier to proof that something is wrong, namely when it is illogical.
One example is your explanation of the faster-than-wind vehicle. You explain that the propeller is using the energy from the wind.
So if energy 3 (rotor) is the same as energy 2 (sail boat tack) and exceeds energy 1 (vehicle drag) which is required to overcome the resistance of the vehicle, the vehicle will be propelled at x velocity. Lets not forget that a vehicle running with the wind will require less of energy 1 than if it were to run perpendicular or into the wind because of drag. This helps also.
This is in clear contradiction to other descriptions of the same process. I think even you said that the wheels are driving the propeller, not the other way round once the vehicle goes faster than the wind. You cannot have it both ways (this is the logical argument)
BTW, I am starting to get a glimpse that the faster than wind vehicle might be possible. Just not with the mechanism you describe.
From the aspect of conservation of energy I accept some points from Krass.
A possible source of energy is blowing air backwards with the propeller, so that finally a volume of air is moving more slowly than it did before. This difference in energy could go into the higher speed of the car.
Krass,
I still have a principle problem with your explanation of geared speed.
If we assume ideal conditions:
- indestructible materials,
- no friction
- no limit to forces
- perfect grip (this is not in contradiction to no friction as it could be like a gearl reailway track)
- no heat problems
and you move the middle strip a half light speed, having a gear ratio of 1:3 you would move the car at 1.5 times the speed of light. This brings it in clear conflict with accepted physics.
TonyT,
the electrostatic forces you mention are so small in comparison to the other forces that they are irrelevant.
This is different for the small critters like spiders, flees or lice. They live in a totally different world, where electrostatic forces, surface tension, viscosity effects and forces per volume change everything in life as we know it.
My searching is confirming your comments about text-books and the gaps in our knowledge about electrostatics.
s2s
I have been told/read and I have accepted/believed that the electrostatic forces are "so small".
Pollack's example of thinking independently and the logic in his argument about the forces that hold clouds ("elephants") in the sky has challenged me to question my "fundamental" beliefs.
To decide whether my "beliefs" are correct I now want to calculate numerical values for the electrostatic forces.
So far I have not found an equation to calculate a value for the number of coulombs of negative electric charge that will accumulate on an object (eg on a table tennis ball) in a wind-stream (eg the air-flow from a hair dryer or a vacuum cleaner).
I now suspect that the electrostatic forces are of a significant size.
sun2steam said:
JB, you explained just nicely that science cannot 'proof' anything, but just give probabilities. I tried to explain that to you for a long time.
However it is much easier to proof that something is wrong, namely when it is illogical.
Are you saying we were on the same page all along it's just that your perspective was different to mine? Crazy! lol
A high case of probabilities does not make it so, neither can it form the basis for conclusive un-defyable proof. ie science (we) have still a lot to learn, not everything is yet peer reviewed or invented. My mantra entirely.
sun2steam said:
One example is your explanation of the faster-than-wind vehicle. You explain that the propeller is using the energy from the wind.
This is in clear contradiction to other descriptions of the same process. I think even you said that the wheels are driving the propeller, not the other way round once the vehicle goes faster than the wind. You cannot have it both ways (this is the logical argument)
"To put it in a sentence: the cart accelerates direct down-wind to near wind speed with its rotor acting as a wind-driven turbine driving the wheels, and then further accelerates to 2.8 times wind-speed with its road-driven wheels driving the same rotor acting as a propeller."
Which is different to what I initially thought was being described. Hence the propeller acts as power source for the wheels at lower speeds and means of propulsion at higher speeds.
Curiouser and curiouser...
To which I responded:
Jeffbloggs said:
Fireflies
Funny I said that in the beginning...
The wheels propel the vehicle over the speed of the wind BUT from the energy captured by rotor from the speed of the wind over the ground. It's all angles, fulcrums and levers!
Question: Will the DDW propel itself without the rotor? Will it propel itself without the true wind speed of air over ground just by using it's wheels? I think you'll find the answer is no. How could it? It needs the propeller to "close the loop" of leverage, you cannot lever anything without a fulcrum.
The relationship to the various anchors or "fulcrums" of "leverage" are intertwined. The "gearing" of the system allows the relevant leverage between the ground and the wind speed to propel the vehicle. The wheels might increase the speed of the vehicle over the ground, even via the rotor as a propulsion propeller, but the "wheels" by themselves will not harvest any energy from the wind for propulsion. It's purely the fulcrum with which it leverage's the vehicle to accelerate. Just like in the video with the black line representing the lever between the ground and the air. Watch it again above. (BTW I also mentioned in one of my posts that the wheels propelling the vehicle was a bit of a "red herring" in that the statement they made (not me, I only copied it), that the wheels were used to drive the rotor, detracted from the fact that without the rotor no energy could be adsorbed from the wind over ground airspeed.
sun2steam said:
BTW, I am starting to get a glimpse that the faster than wind vehicle might be possible. Just not with the mechanism you describe.
I agree words are hard to use if everyone is using their own terms and meanings. Including me. Would you care to elaborate on your version?
sun2steam said:
From the aspect of conservation of energy I accept some points from Krass.
A possible source of energy is blowing air backwards with the propeller, so that finally a volume of air is moving more slowly than it did before. This difference in energy could go into the higher speed of the car.
Sounds like the concept I proposed with the toroidal vortex craft, where we also discussed the dynamics of the X-Zylo. That was a while ago, do you remember that debate?
sun2steam said:
Krass,
I still have a principle problem with your explanation of geared speed.
If we assume ideal conditions:
- indestructible materials,
- no friction
- no limit to forces
- perfect grip (this is not in contradiction to no friction as it could be like a gearl reailway track)
- no heat problems
and you move the middle strip a half light speed, having a gear ratio of 1:3 you would move the car at 1.5 times the speed of light. This brings it in clear conflict with accepted physics.
You couldn't possibly mean this S2S:
Possibly the similar type of dynamic that is being discussed here but just on a different scale. Read the article here:
You should know by now that nothing is impossible for us "trekies". Teleportation tick. Tricorder tick. Warp drive tick. Funny costumes tick. Alien race bent on earth destruction tick. Ooops that's us! lol
If we assume ideal conditions:
- indestructible materials,
- no friction
- no limit to forces
- perfect grip (this is not in contradiction to no friction as it could be like a gearl reailway track)
- no heat problems
and you move the middle strip a half light speed, having a gear ratio of 1:3 you would move the car at 1.5 times the speed of light. This brings it in clear conflict with accepted physics.
In classical mechanics there is no problem with all that. In relativity you can't have perfectly rigid indestructible materials. They would allow faster than light information transfer. Think about a very long rod that you spin up until the tip would have to reach light speed, if it was perfectly rigid. And "no limit to forces" is not enough either, because the force required at the rack would go to infinity, when the cart speed approaches light speed.
One example is your explanation of the faster-than-wind vehicle. You explain that the propeller is using the energy from the wind.
This is in clear contradiction to other descriptions of the same process. I think even you said that the wheels are driving the propeller, not the other way round once the vehicle goes faster than the wind. You cannot have it both ways (this is the logical argument)
There is no contradiction between "getting energy from the wind" and "wheels are turning the propeller".
- Getting energy from the wind, refers to true wind (wind relative to the ground), which is being reduced.
- Wheels are turning the propeller, means that the propeller turns according to the torque transmitted from the wheels, against the torque from the air.
Both is correct. The same happens with the walkway cart (the first one):
- It is getting energy from the movement of the walkway relative to the ground.
- The walkway wheels (= propeller) turn according the torque transmitted from the ground wheels, against the torque from the walkway.
Krass,
Thank you for the explanation. I accept and agree with your explanation.
JB,
"Are you saying we were on the same page all along it's just that your perspective was different to mine? Crazy! [;)] lol"
No, I had been saying in a polite way that you demonstrate that you don't understand the concept of science.
It is fascinating that you always try to add another layer of complexity.
"
sun2steam said:
From the aspect of conservation of energy I accept some points from Krass.
A possible source of energy is blowing air backwards with the propeller, so that finally a volume of air is moving more slowly than it did before. This difference in energy could go into the higher speed of the car.
Sounds like the concept I proposed with the toroidal vortex craft I proposed, where we also discussed the dynamics of the X-Zylo. That was a while ago, do you remember that debate? "
What do you need a vortex for in this case?
What's next? Coriolis force, electrostatics or most likely some effect related to Tesla?
My explanation of the different energies is quite simple. When you stand on a boat and jump, the boat will end up with the same kinetic energy that you have, just in the opposite direction.
Same with the propeller vehicle. If the propeller reduces the kinetic energy of a volume of air by reducing its speed in relation to the ground this energy can somehow be transferred into the vehicle and move it faster. Now in the case of the propeller vehicle I 'only' have to find out where the force in the legs (from the boat example) is coming from.
I am slowly getting there in my imagination by replacing the middle strip in the geared toy car video by a 'string of air' moving above ground and the propeller in the air being the 'front wheels'. I still don't trust my judgement and will sleep over it.
"Are you saying we were on the same page all along it's just that your perspective was different to mine? Crazy! lol"
No, I had been saying in a polite way that you demonstrate that you don't understand the concept of science.
It is fascinating that you always try to add another layer of complexity.
I think I'll take that as a compliment. Let me know if you are interested in knowing why. You really like testing my verbal judo! I did not mean to be un-polite and my "lol" was genuine not sarcastic. It always amazes me that regardless of the "conflict of interests" there is still so much communality. How tormented are we by perspective!
sun2steam said:
sun2steam said:
From the aspect of conservation of energy I accept some points from Krass.
A possible source of energy is blowing air backwards with the propeller, so that finally a volume of air is moving more slowly than it did before. This difference in energy could go into the higher speed of the car.
Sounds like the concept I proposed with the toroidal vortex craft, where we also discussed the dynamics of the X-Zylo. That was a while ago, do you remember that debate?
What do you need a vortex for in this case?
What's next? Coriolis force, electrostatics or most likely some effect related to Tesla?
Actually the toroidal vortex effect is quite common in nature, just not harnessed or well understood by man yet. I would greatly enjoy discussing the mechanics (fulcrums, levers and forces) of them with you again. You can watch a collection of them here, it's really worth it. (the real footage only starts at the 0:30 second mark).
Once you get to know them you start seeing them everywhere.
S2S, I suppose I should of called it smoke ring ship, but that just doesn't sound cool (seeing that smoking is out of fashion now). How did you like the "little smoke rings" in the video above at 3:14?
Coriolis force or electrostatics are all results of the same field of forces we "float" in, all different names for "virtually" the same thing, if you get down to the fundamentals. On relevance to the "smoke ring ship", one of the effects used for propulsion in the concept was the "lifter" effect I showed you again recently, which you said worked by electrostatic effect. So yes it is included and in fact critical to keep the toroidal vortex laminar around the craft whilst it moves through a fluid or air. The "ship" itself is merely a craft that stays within the toroidal vortex and share the same shape of the vortex, but in order to do so must maintain the vortex.
I sometime wished that Tesla was around so he could explain to us how he thought AC induction motors really work, and how somewhere along the way of making them for a hundred years or so, someone decided to loose the other half of the plan so that they could "charge" for "power".
sun2steam said:
A possible source of energy is blowing air backwards with the propeller, so that finally a volume of air is moving more slowly than it did before. This difference in energy could go into the higher speed of the car.
This is correct in the reference frame of the ground. The cart leaves a wake of slowed air behind it, just like any other sailcraft.
sun2steam said:
When you stand on a boat and jump, the boat will end up with the same kinetic energy that you have, just in the opposite direction.
I think you mean momentum, not kinetic energy here. The kinetic energies would only be equal if the masses were equal.
sun2steam said:
Now in the case of the propeller vehicle I 'only' have to find out where the force in the legs (from the boat example) is coming from.
I don't think it is a good analogy. You interact only with one object (the boat) instead of two (air & ground) and you use internally stored energy to generate the force with your legs, while the cart uses no internally stored energy for propulsion.
sun2steam said:
I am slowly getting there in my imagination by replacing the middle strip in the geared toy car video by a 'string of air' moving above ground and the propeller in the air being the 'front wheels'.
That is the right path of thought. Imagine you hold the gear cart still while the paper moves, and then release it. It will quickly accelerate to say twice paper speed. A propeller in air has more slippage, so this acceleration takes much longer and you will never reach exactly the speed you geared it for. But otherwise it is the same. Nothing special happens when then the gear cart overtakes the paper during acceleration, and nothing special happens when then the propeller cart overtakes the airmass during acceleration.
Here is a diagram that relates those various gears to the rotor carts:
Hey Krass
Great info once again. You're making me even more curious what your background is and how you came by all this specific info...lots of passionate googling?
BTW do you care to comment on the sailing hydrofoil (flapping wing) concept I proposed on the first page of this thread at the end of the page? Would really appreciate any feedback on the concept. Structurally obviously there still some challenges, but propulsion wise I'm hoping it's viable.
Regards
JB
Googling to find an equation that can be used to calculate how many coulombs of electrostatic charge will accumulate on an object due to the movement of air over the object has uncovered the following links:
Q. Is the force on an aerofoil a combination of Bernouilli plus Coanda plus electrostatics ?
Why aerofoils work primarily involves Bernoulli, Coanda Effect and complex vorticity.
Henri Coanda invented many things which included the world's first jet aeroplane that he built and flew in 1910. Phenomena observed during the one and only test flight directly led to him filing a patent (No. 2,108,652) on 15/02/1938 (mentioned earlier in this thread) for the Lenticular Disc, otherwise known as a flying saucer.
Posted Wednesday 5 Dec 2012 @ 6:56:13 am from IP #
TonyT
I'm not avoiding your posts...I'm just not trying to distract to much from the DDW conversation to see if everyone is on the same page. After that I'll resume "transmission of the normal program".
On clouds, atmospheric energy potentials or weather, UFO lights and elephant mind control, look up harrp. It is the "sound" of things to come.
Posted Wednesday 5 Dec 2012 @ 7:14:56 am from IP #
Russel
I could put together a RC model version. I'd prefer to use an electric hybrid version though, I don't think I'll be able to match the dynamics of the system otherwise. Like that I only have to optimise rotor/generator and water prop/motor. I can get it to around +85% elec. efficiency, and the "battery" boost could help get us up to plane, otherwise we won't have a chance. I can also source variable pitch rotor's and water propellers (aka 500 or 600 size RC helicopter gimbals + rotors up to +1m diameter)
My biggest concern is the requirement of a keel or the like to counteract the force on the turbine. The keel brings with it quite a bit of drag, which the land version simply never has to deal with. So without some numbers as a guideline on the amounts of energy vs drag, it's going to be a bit touch n go in the water I think.
One thing that the propellor under water will have is traction "problems" (aka slip), in comparison to the land vehicle. That's why I tried to "skip ahead" with my hydrofoil sailing "sculpture" on page 1, Mr Flappy Wingfin, and use fins that are directly leveraged against the wing, and by controlling the AOA on both avoid having any substantial "keel" effect to contend with.
Do you know where to start with the gearing calculations, keel arrangement and relevant drag? Maybe Kraas can help out? I'd be happy to help in the design/prototype department.
Regards
JB
Posted Wednesday 5 Dec 2012 @ 12:21:08 pm from IP #
Russell Moore said:
Would anyone care to try and build a DDWFTTW water borne model? Would propeller/s do the same job as the wheels on the DDWFTTW land craft?
For DDWFTTW on water you would need a turbine underwater, instead of the wheels. This is less efficient than wheels, and you have more hull drag too. So the whole trick is much more difficult on water, compared to land. It might get above wind speed, but nowhere near 3 times faster.
Krass said:
For DDWFTTW on water you would need a turbine underwater, instead of the wheels. This is less efficient than wheels, and you have more hull drag too. So the whole trick is much more difficult on water, compared to land. It might get above wind speed, but nowhere near 3 times faster.
Hey Krass
Thanks for just saving us a heap of time! Also as per my previous post to you do you have any thoughts about the Wingfin concept on page 1. Even just a viability index between 1-10, just to see if I'm barking up the right tree, would be nice! Thx
BTW was there anything in my explanations as a "layperson" that was untowards? Always looking for confirmation or correction so I don't embark pursuing ideas that aren't worth it.
Regards
JB
Posted Wednesday 5 Dec 2012 @ 12:36:17 pm from IP #