PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2024-11-26, 15:34:35
News: If you have a suggestion or need for a new board title, please PM the Admins.
Please remember to keep topics and posts of the FE or casual nature. :)

Pages: [1] 2
Author Topic: Archimedes' screw applied to electricity  (Read 4440 times)
Group: Moderator
Hero Member
*****

Posts: 2072
Basic concept:
Apply the Archimedean screw principle to electric current, turning this water pump into an electron pump.

The Archimedes screw is a helical surface surrounding a central cylindrical shaft placed obliquely with its bottom end in the water. Its rotation allows the water to flow upwards, which, by the earth's gravity, is maintained at the bottom of each loop of the screw. A more "modern" version, revisited by Leonardo da Vinci, is to use a helical tube instead, see attached diagram.

The idea: replace the helical tube by a solenoid, replace the water by electrons, replace gravity by an electrostatic field obtained by a positively charged plate placed on one side along the solenoid. The free electrons attracted by the plate being maintained on one side only of the solenoid, the rotation of the solenoid makes appear a relative movement of the electrons, thus a current. This would require rotating contacts, so we will make it simpler.
Instead of rotating the solenoid, we will use a fixed solenoid and a rotating plate, see second diagram. The electrons of the solenoid will be attracted by the plate and follow its rotation. They will turn in the solenoid, creating a current.
As we all prefer, I think, solid state rather than mechanical rotation, the final idea is to replace the rotating plate by two pairs of diametrically opposed fixed plates, fed in quadrature to create a rotating field.


---------------------------
"Open your mind, but not like a trash bin"
   
Group: Moderator
Hero Member
*****

Posts: 2072
Note that since electrons move very slowly in a conductor, the rotation will have to be done very slowly too (linear speed of the order of mm/s), otherwise it is not sure that the electrons can follow the plate because they are subject to the resistance of the conductor.

I don't know if it can work. If it works, I don't know how much current we can reach. Finally I have no idea of practical application nor if it can be a way for energy. I have not seen the principle applied anywhere in a conductor. A similar idea is exploited in travelling wave tubes, but there it is in vacuum, not in a conductor. So it's just something I would like to test.
I already tried to apply the idea to dielectrics (it's on this forum), but it's impossible because the effect on positive charges cancels the one on negative charges. But in a conductor, it should work. Before I go into a practical realization, please tell me if you see any objections to the possibility of operation.


---------------------------
"Open your mind, but not like a trash bin"
   
Group: Ambassador
Hero Member
*****

Posts: 4045
Can I share your hypothesis a bit ? ( for more eyes and opinions?
There is a moderated board at Stefan’s for this “open source sharing”!

No worries either way ( feel free to remove this post if … for any reason
Thanks for sharing
Chet
EDIT for comment below
I will pm you ..as some of your points need clarity!
   
Group: Moderator
Hero Member
*****

Posts: 2072
Can I share your hypothesis a bit ? ( for more eyes and opinions?
There is a moderated board at Stefan’s for this “open source sharing”!
...

Chet,

This thread is public so there is nothing to stop anyone talking about it elsewhere. So feel free to share but please, not anywhere: I wouldn't appreciate it at all if it was done on overunity.com or energeticforum.com, sites that have censored me and where I can't post anymore. I would be very annoyed to find there anything that I put here, next to the fakes and nonsense that are found in great quantity on these sites and that skeptics are prevented from commenting. :(

Thanks


---------------------------
"Open your mind, but not like a trash bin"
   
Sr. Member
****

Posts: 331
Hi F6FLT,

Reading this thread reminded me of the patent attached...

Fred
   
Group: Moderator
Hero Member
*****

Posts: 2072
Hi Fred,

Only the helical strip has something in common with my setup since in the patent we are dealing with a magnetic generator device without any link with electrostatics, and whose principle is conventional: the rotation of the ferromagnetic helical strip changes the reluctance of the magnetic circuit between the two poles of the electromagnet, and thus we have a variation of flux which induces current in the coil 3 (fig. 1).

On the other hand, it can also be seen as an Archimedean screw in which, contrary to my setup, it is not the electrons that replace the water, but the magnetic flux. This new idea opens a perspective but with a very different setup.
I will think about it but after the implementation of the device that I presented above. I just got the motor of a microwave oven to make the plate connected to the HV power supply turn around the coil, with a regular movement.


---------------------------
"Open your mind, but not like a trash bin"
   
Hero Member
*****

Posts: 2735
F6FLT
Quote
I don't know if it can work. If it works, I don't know how much current we can reach. Finally I have no idea of practical application nor if it can be a way for energy. I have not seen the principle applied anywhere in a conductor. A similar idea is exploited in travelling wave tubes, but there it is in vacuum, not in a conductor. So it's just something I would like to test.

It does work and I built and tested the device you posted around 2012. I also used this setup to calibrate a rotating coil atmospheric charge detector which were common in the late 1800's. As the coil rotates some electrons are dragged along due to the positive charge of our atmosphere. This charged a small capacitor with one terminal also connected to ground. The voltage on the capacitor gives us an indication of the difference in potential (V/cm) between the atmosphere and ground. The larger the loop the better and most used coils around 36" in diameter.

I was experimenting with this stuff when researching Lord Kelvins work and I believe it was he who used this setup.

These kinds of devices were later replaced with the atmospheric field mill still in use today which doesn't require brushes.
https://en.wikipedia.org/wiki/Field_mill

AC






---------------------------
Comprehend and Copy Nature... Viktor Schauberger

“The first principle is that you must not fool yourself and you are the easiest person to fool.”― Richard P. Feynman
   
Sr. Member
****

Posts: 331
Hi F6FLT,

I must admit I had only skimmed the thread when I sent the patent. I saw the word Archimedes Screw and the patent jumped into my mind. It was no deeper association than that. After reading I found it different and more interesting than I originally thought.

I think you could accomplish this in a semiconductor where you would have electron drift current in presence of an E field. I don't think it would work in a conductor since an E field doesn't penetrate it-- you would have to connect a wire to a conductor to get the current, which would bring you back to the conventional situation.

https://en.wikipedia.org/wiki/Drift_velocity
 
The simplest case might be a semiconductor cylinder with a charged disc at one end. For clarity we say the disc isn't touching the cylinder and that no current comes from it. This would be the case with an Electret, the electric equivalent of a permanent magnet.

Electrons and holes will flow and a current is generated. Since the E field doesn't lose charge in this process, how is energy conserved in this system?

It's also interesting to note that the electron drift current increases with the temperature of the semiconductor so there seems to be a bit of a Maxwell's Demon happening with the presence of the E field...if not the random thermal movements of the electrons/holes would still cancel out regardless of the presence of the E field...

Fred

   
Group: Moderator
Hero Member
*****

Posts: 2072
@AC

I would have already posted something similar in 2012?! I don't remember, I have a very bad memory :(. Do you have the reference?


---------------------------
"Open your mind, but not like a trash bin"
   
Group: Moderator
Hero Member
*****

Posts: 2072

I don't think it would work in a conductor since an E field doesn't penetrate it

When you think about the capacitor, it is clear that an external E-field from a plate attracts electrons to the surface of the other one. If you slide a small polarized plate over a long conducting strip, the electrons in the strip will always be attracted to the sliding plate.
The question is therefore whether this effect leads to a longitudinal displacement of charges in the strip, or whether it is a simple tidal effect like the moon making the water of the oceans rise in its direction while rotating around the earth, but without horizontal displacement of water.
This case, equivalent to your objection, also corresponds to what we read in the courses since an E field external to a conductor can only have an orthogonal component at its surface.

On the other hand, in the case where the screw rotates and the plate remains fixed, it is clear that there is an excess of electrons in the part of the coil close to the plate. As the coil rotates and the electrons remain at the same position, we have a displacement of the conductor relative to the electrons, thus a displacement of the electrons relative to the conductor, thus a current. As this effect is the reciprocal of the one with the fixed coil and the rotating plate, this questions it.
How would you explain an absence of current with the fixed plate and the rotating coil?

Quote
I think you could accomplish this in a semiconductor where you would have electron drift current in presence of an E field.  [...]

The simplest case might be a semiconductor cylinder with a charged disc at one end. For clarity we say the disc isn't touching the cylinder and that no current comes from it. This would be the case with an Electret, the electric equivalent of a permanent magnet.

Electrons and holes will flow and a current is generated. Since the E field doesn't lose charge in this process, how is energy conserved in this system?

It's also interesting to note that the electron drift current increases with the temperature of the semiconductor so there seems to be a bit of a Maxwell's Demon happening with the presence of the E field...if not the random thermal movements of the electrons/holes would still cancel out regardless of the presence of the E field...

Fred

I do not see very well the constitution of the device, in particular the circuit in which this current would circulate. When we place the charged disk, I understand that it causes a displacement of electrons and holes. But how could it continue indefinitely? The restoring coulombic force inside the semiconductor will make them reach an equilibrium.



---------------------------
"Open your mind, but not like a trash bin"
   
Group: Moderator
Hero Member
*****

Posts: 2072
https://youtu.be/UcwBmqd60C4
Privately I did receive this opinion from smokey

Neutral or nil result to be expected!
not sure this is appropriate to place this response here ( will check with him later

Chet

It is a possibility that the result is zero, for the reason I indicated above in response to Orthofield's relevant objection.
A field orthogonal to the surface can't exert a work for a longitudinal movement of the charges.

But if the rotation of the plate does not drive the electrons, on the other hand it is not clear why the reciprocal case of the fixed plate and the rotating coil would not work.  If the answer to this question also allows to foresee a null effect, then the starting idea will have to be revised for a work around of the problem of the orthogonal field. This work around could be the use of a charged dielectric instead of a conductor.



---------------------------
"Open your mind, but not like a trash bin"
   
Hero Member
*****

Posts: 2735
F6FLT
Quote
I would have already posted something similar in 2012?! I don't remember, I have a very bad memory

No, if you read my post I said I built and tested the Archimedes' screw principal for electricity your talking about and posted. The device and principal was actually invented in the late 1800's and used to measure atmospheric electricity. Thus it is not new or unique in any sense of the word.

AC


---------------------------
Comprehend and Copy Nature... Viktor Schauberger

“The first principle is that you must not fool yourself and you are the easiest person to fool.”― Richard P. Feynman
   
Sr. Member
****

Posts: 331
Hi F6FLT,

Yes, I see what you mean, there would be a concentration of charge on the surface of the (metal) screw opposite the plate, and that would make an apparent current as the screw rotated. I guess the question, to be answered by experiment, is whether energy consumed to rotate the screw + energy lost in resistance (ie charge 'friction') can be less than the power dissipated in a load attached to the screw.

My circuit was not well thought out. To demonstrate drift current in a semiconductor device, one can use a voltage source and high impedance in parallel with it, with the load resistance in parallel with those two legs. There are then two components to the current through the load, a small residual current from the voltage source, and the drift current. By using a pure voltage source like an electret, unconnected to the semiconductor, I was trying to bring out the fact that the drift current is additional to any current caused by the voltage source. But in that case, as you said, the semiconductor would simply polarize and the drift would stop. In the case where there is a wire connection, the drift current doesn't stop, as long as the voltage is present. 

It still seems to me that there's the possibility of generating useful power from the heat around the semiconductor. Then the voltage is in effect aligning the thermal energy in one direction, like a Maxwell's Demon. But none of this is relevant to your concept, and I'll take it to another thread here.

Fred
   
Group: Moderator
Hero Member
*****

Posts: 2072
Hi F6FLT,

Yes, I see what you mean, there would be a concentration of charge on the surface of the (metal) screw opposite the plate, and that would make an apparent current as the screw rotated...

That's exactly it, you have captured the effect that I hope. Since this would be the work of the Coulomb force, I don't believe there would be OU there. But what interests me here is to have an additional degree of freedom in the way of coupling circuits, so as to imagine in a second stage, more sophisticated systems than those seen so far which gave nothing.
It remains to be seen if there would really be a current. I hope to be able to experiment it in about ten days.

Quote
...
My circuit was not well thought out. To demonstrate drift current in a semiconductor device, one can use a voltage source and high impedance in parallel with it, with the load resistance in parallel with those two legs. There are then two components to the current through the load, a small residual current from the voltage source, and the drift current. By using a pure voltage source like an electret, unconnected to the semiconductor, I was trying to bring out the fact that the drift current is additional to any current caused by the voltage source. But in that case, as you said, the semiconductor would simply polarize and the drift would stop. In the case where there is a wire connection, the drift current doesn't stop, as long as the voltage is present. 

It still seems to me that there's the possibility of generating useful power from the heat around the semiconductor. Then the voltage is in effect aligning the thermal energy in one direction, like a Maxwell's Demon. But none of this is relevant to your concept, and I'll take it to another thread here.

Fred

Your idea is worth trying out too. A Maxwell demon is part of the possibilities of FE, the principle has not been invalidated in the general case, only in some particular cases. An electric Maxwell demon has already been proposed and experimented. The current was very low, so I'm not sure if all the experimental artefacts have been eliminated but maybe. It is not a semiconductor that is used, the depletion zone will have to be replaced by the junction between electrodes in a vacuum tube, where the work function of two electrodes is biased by a magnetic field and not by an electret. There is a little family resemblance with your idea, so I put the two pdf that deal with it, from the same authors: https://arxiv.org/pdf/physics/0311104 and https://arxiv.org/pdf/physics/0509111
The experiment: https://www.youtube.com/watch?v=FCCPeEKIVvQ

If you start experimenting with your idea, I will follow it with attention.



---------------------------
"Open your mind, but not like a trash bin"
   
Sr. Member
****

Posts: 331
Hi F6FLT,

Thanks for sending those references and the video! I was aware of this principle already from other sources, but it is very helpful to see it demonstrated.

There's a US patent that covers this principle, from 1959. See attached. Fig. 2 in the patent is identical to a diagram shown in both of the two papers you sent. The operating principle is described at the bottom of col. 3 on pg. 7.

The Hatsopoulos device has an ES field created by batteries, and thus moves more into the area that I'm interested in--except that I want to do it in solid state to avoid using tubes, etc.

The principle of nonreciprocality, or time-irreversible, or 'rachet' processes is important for understanding this area. It was I believe Casimir, or possibly Onsager who said that a magnetic field was necessary to create electrical nonreciprocity, as we see in the Hall effect. But the rise in drift current with increased temperature seems to indicate something of a rachet effect with only an E field.

Yes, I'm planning an experiment now. I'm going to use a thermoelectric module, and bias it with 20 V or so (I'm just guessing as to correct bias at this point), and see if any noticeable power is generated when the module is in a uniform heat bath (my oven on warm). I don't have much in the way of test equipment so measurements will be crude.

Fred

   
Group: Moderator
Hero Member
*****

Posts: 2072
Hi fred

The ratchet technique for recovering useful energy from heat seems simple. After all, a simple diode that rectifies the noise of a resistor would be sufficient.
The problem is the threshold effect. The noise does not exceed the threshold of the "ratchet" that is the diode, so it does not work.
You would need a very low threshold, but then it would also be subject to thermal noise, and the temperature and noise being the same on both sides, you would lose the functionality of the diode.

This is a general principle problem with single temperature thermal baths. For example, it is not well known, but a solar panel that would be at the same temperature as the sun will no longer work (even if it was designed to withstand this temperature). Even for a solar panel, there must be a temperature difference between the source and the load.
So it is clear that we need an additional "trick", like the irreversibility or non-reciprocity you are talking about. We saw from the Chinese patent that the magnetic field was a possibility. I don't know of any other.

I haven't looked at the patent you provided yet, I will.


---------------------------
"Open your mind, but not like a trash bin"
   
Sr. Member
****

Posts: 331
Hi F6FLT,

My basic idea is to stimulate the noisy/heated system with an E field. This will work as long as the field source consumes little or no power. I've seen no evidence that drift current requires an additional current from the bias--only a 'pure' voltage-- so I think it will work.

To the larger point, one CAN create a 'noise-free' volume that noise energy will flow into. Harold Black demonstrated this in a now forgotten patent, attached. Black invented the negative feedback circuit, and in this patent he showed that it's possible to feed noise back on itself to create a zero noise circuit. I quote the patent at length here so you won't need to read all of it. He reports on pg. 9 of the pdf, that "I have discovered that feedback action can produce resistances or generalized impedances free from resistance-noise---that feedback action can transform ordinary resistances (or generalized impedances) to resistances (or generalized impedances) that are free of all noise, including thermal agitation. For example, if the net across the bridge points of the input hybrid coil be a resistance, the feedback can transform this resistance by producing an enlarged copy of it as the amplifier input impedance, this copy having the remarkable property of freedom from resistance-noise." 

As one would expect, if there is no resistance noise in one part of the circuit, another part of the circuit must lose some of its thermal noise to it to restore balance, and this is the case. On the same page he reports: "I have discovered that feedback action can abstract heat from a body. When a resistance is connected to an amplifier, feedback action can be made to abstract heat from the resistance or cool it. For example, if an electric conductor or resistance be connected across resistance of the type described above as free from resistance noise, the effect of making the connection is to abstract heat from the ordinary resistance or cool it, the Ordinary resistance receiving no energy from the other resistance but giving up energy of thermal agitation to the other resistance in the form of an electric current. To observe the cooling effect the resistance to be cooled can be heat insulated. If it is not insulated, the small losses due to thermal agitation are readily replaced from the relatively vast reservoir of heat surrounding
the unit." These noiseless amplifiers were later developed for Radio Telescopes by Robert Forward.

So here is a purely electronic heating and cooling effect, and a purely electronic extraction of noise energy. My point in going on at length about this, aside from what I consider the inherent interest, is that most attempts to cohere thermal noise take a passive approach, but an active approach is probably going to be more fruitful-- as long as energy needed to cohere the noise is less than that provided by it. That's the main question.

This is far afield from the original subject of this thread, but it seems to interest you as well, so I leave it here.

Fred
   
Group: Guest
Hi F6FLT,

Yes, I see what you mean, there would be a concentration of charge on the surface of the (metal) screw opposite the plate, and that would make an apparent current as the screw rotated. I guess the question, to be answered by experiment, is whether energy consumed to rotate the screw + energy lost in resistance (ie charge 'friction') can be less than the power dissipated in a load attached to the screw.

My circuit was not well thought out. To demonstrate drift current in a semiconductor device, one can use a voltage source and high impedance in parallel with it, with the load resistance in parallel with those two legs. There are then two components to the current through the load, a small residual current from the voltage source, and the drift current. By using a pure voltage source like an electret, unconnected to the semiconductor, I was trying to bring out the fact that the drift current is additional to any current caused by the voltage source. But in that case, as you said, the semiconductor would simply polarize and the drift would stop. In the case where there is a wire connection, the drift current doesn't stop, as long as the voltage is present. 

It still seems to me that there's the possibility of generating useful power from the heat around the semiconductor. Then the voltage is in effect aligning the thermal energy in one direction, like a Maxwell's Demon. But none of this is relevant to your concept, and I'll take it to another thread here.

Fred

I experienced something akin to this with electrostatics. When an isolated charged plate was providing the inducing charge, the induced current was entirely separated from the charge current induction/depletion cycle.
which leads to external circuits powered by the independent electrostatic machines.

Otto von Guericke (et all)
   
Sr. Member
****

Posts: 331
Hi Sm0key2,

If I understand you correctly, something like a (solid state?) ES source with a pulsating field strength was inducing a current in a circuit nearby? And that current didn't vary with the charge/discharge of the source? If so, very interesting!

I'm aiming at as close to an electrostatic source as I can get, although relatively low voltage.

Fred
   
Group: Guest
That’s not to say to use a sulfur plate in your experiments, but the principal of the nature would imply if the plate carries the charge of the conductor above, and was of sufficiently larger area than the perpendicular surface of the curvature of the coil, moving the field or coil would induce a charge. An opposing electrical ‘drag’ will occur if the charge carrier is conductive at those voltages.

To paraphrase Tinsel Koala: it works best when the charge carrier is a pure dielectric
   
Group: Guest
Hi Sm0key2,

If I understand you correctly, something like a (solid state?) ES source with a pulsating field strength was inducing a current in a circuit nearby? And that current didn't vary with the charge/discharge of the source? If so, very interesting!

I'm aiming at as close to an electrostatic source as I can get, although relatively low voltage.

Fred

To put it clearly, the electrostatic source of any type is connected to an externally charged plate, that is isolated physically from outside systems.

another electrostatic inductor is moving through the field that is created on the plate.

A similar example is the separation of the charge mechanism of a van de graff and the discharge of charged sphere(s) connected to its’ output
   
Group: Moderator
Hero Member
*****

Posts: 2072
To put it clearly, the electrostatic source of any type is connected to an externally charged plate, that is isolated physically from outside systems.

another electrostatic inductor is moving through the field that is created on the plate.

A similar example is the separation of the charge mechanism of a van de graff and the discharge of charged sphere(s) connected to its’ output

With the Archimedean screw, the question is to create a direct current from the rotation of the screw in a field or conversely by rotating the field around the screw.

The simple movement of a plate in a field amounts to a variable capacitive coupling between the plate and the conductors that generate the field. So if a circuit connects the moving plate to the ground, a current will flow during the time of the displacement since C and U can vary and i= dQ/dt = d(C.U)/dt = U.dC/dt + C.dU/dt.

In the case of the Archimedean screw, the capacitance between the plate and the solenoid is constant, as is its voltage. As I am not claiming OU here but only a way to drive a current in a circuit from an external voltage, the energy would come from the one needed for the rotation, not from the voltage that polarizes the plate (as in the case of the Faraday disk, where the energy does not come from the source of the magnetic field). It is therefore important to understand this so as not to mix it with devices with variable capacities and potentials, and therefore unrelated.
I'm not at all sure it will work, I even have good reasons to think it won't, but a little doubt will make me try anyway.



---------------------------
"Open your mind, but not like a trash bin"
   
Group: Moderator
Hero Member
*****

Posts: 2072
@Fred

The principle of Hatsopoulos' patent is indeed very close to the Chinese Maxwell's demon in the way of using the magnetic field to promote the movement of electrons from the hot plate to the cold plate. But I wonder why this temperature difference since it should work as well with hot plates only. The extraction of electrons from a hot plate and then their deflection by the field seems to be the only condition necessary for operation.


---------------------------
"Open your mind, but not like a trash bin"
   

Group: Professor
Hero Member
*****

Posts: 1940
Hi F6FLT,

Thanks for sending those references and the video! I was aware of this principle already from other sources, but it is very helpful to see it demonstrated.

There's a US patent that covers this principle, from 1959. See attached. Fig. 2 in the patent is identical to a diagram shown in both of the two papers you sent. The operating principle is described at the bottom of col. 3 on pg. 7.

The Hatsopoulos device has an ES field created by batteries, and thus moves more into the area that I'm interested in--except that I want to do it in solid state to avoid using tubes, etc.

The principle of nonreciprocality, or time-irreversible, or 'rachet' processes is important for understanding this area. It was I believe Casimir, or possibly Onsager who said that a magnetic field was necessary to create electrical nonreciprocity, as we see in the Hall effect. But the rise in drift current with increased temperature seems to indicate something of a rachet effect with only an E field.

Yes, I'm planning an experiment now. I'm going to use a thermoelectric module, and bias it with 20 V or so (I'm just guessing as to correct bias at this point), and see if any noticeable power is generated when the module is in a uniform heat bath (my oven on warm). I don't have much in the way of test equipment so measurements will be crude.

Fred
I looked into the possibility of thermionic emission some time ago, I have a number of files on a back-up memory stick somewhere.  The "Nottingham Effect" comes to mind and also the little used "Inverse Nottingham Effect".  The scheme used magnetic fields to direct the cathode emissions away from the anode that supplied the electric field pulling the electrons away to another collecting electrode sitting behind the cathode and therefore not in the electric field.  If anyone is interested, I will dig out the data.

Smudge 
   
Sr. Member
****

Posts: 331
Hi Smudge,

As it happened, I just reviewed one of your papers on this the other day. Here it is.

Fred

   
Pages: [1] 2
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2024-11-26, 15:34:35