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Faraday Disk experiment

  1. Mar 20, 2005 #1
    I am interested in conducting an experiment to prove or disprove the unusual qualities cited by many concerning the Faraday Disk generator.

    I have read from several different sources (some bias and others non bias) that an induced EMF can be measured while rotating an induction disk inside a uniform magnetic field. For obvious reasons this struck me as odd. I am by no means an engineering genius but I do know the basics of electromagnetic induction and one of the basic tenants as taught by current textbooks is that you need a “changing” magnetic field to induce an electrical current.

    The experiments intent is to explore the various methods that Faraday himself explored to induce an electrical current. I have read his notes and am confident I can reproduce his experiments with relative ease. I however will have more modern instruments and the benefit of a hundred years of accumulated knowledge to refer to with my findings.

    I will conduct experiments on just 2 of the configurations he experimented with. One where being the induction magnet and disk are separated and only the induction disk is put into axial motion and the second will be where the magnet and copper disk are fixed together with an adhesive.

    The purpose of the experiment will be to test for input/output efficiency. How much power (not energy) is required to drive the generator compared to how much power is produced. I intend to measure the circuit at full load to establish the constant for the experiment. I feel by placing 100% load on the circuit I can test the other variables such as rotor RPM and power output. This is where I need some advice from those of you who have the education and experience in this area that I lack.

    I am interested in the community’s opinions and suggestions concerning this effort. I am also interested in your opinions with regard to the expected out come of my experiment. Please feel free to offer any constructive criticisms or advice you may have.

    Also I hope this is the appropriate forum for this post.
  2. jcsd
  3. Mar 20, 2005 #2
    have you got a link to Faraday Disk experiments ??
    also as far as a "changing" magnetic field do you mean moving ??
    also i was woking on an experiment where i put a copper plate under a coil and disconnected the coil from any load and noticed that it was still vibrating from the moving magnets above the plate...i could only assume that the plate was conducting a current between the rotating magnetic fields passing above it..and the induced current was itself creating its own magnetic field.. but i also noticed that the vibrations got stronger the closer i put the plate to the magnets , but the plate was NOT drawn into the magnets.. interresting..
  4. Jun 8, 2005 #3
    I realize it’s been a while since I posted the original but I would like to make an update on my progress with this experiment.

    I acquired the following items for my experiment:

    2” X 1/8” nickel plated neodymium disk magnet
    1 7/8” X 3/8” aluminum disk
    Variable speed Dremel tool (5k rpms up to 35k rpms)
    Digital multimeter to measure output
    Multipurpose epoxy resin

    I fixed a drive shaft to the magnet using the epoxy then used the same process to fix the aluminum disk to the magnet.

    I then mounted the Dremel tool to a bench and inserted the experimental piece into the Dremel tool via the drive shaft. I then tested the whole of the set up for continuity. From the drive shaft to the magnet there was no continuity. Magnet to aluminum disk there was continuity. I did not find any reason to measure the resistance between the magnet and the aluminum disk in the experiment because I simply couldn’t see how it would have a negative impact on the results.

    Measured resistance from the radius of the aluminum disk (approximately 7/8”) at measurement setting for the multimeter at 200 ohms was 0.3 ohms.

    At the lowest rpm setting of 5k I took measurements with the multimeter’s factory test leads. I used my free hands to make the contact between the test leads from the multimeter and the test peace. I understand that pressure on the test peace plays a significant roll in the quality of continuity for the experiment however I was not interested in absolutes with this experiment I was interested in proof of principle.

    I took the following measurements:

    Amps – Measurement setting of 200m on the multimeter registered between 1.0 and 0.5
    Note: The speed of the Dremel tool fluctuated based on the pressure of the test leads being applied to the test piece. This resulted in the variable nature of the results.

    Volts – Measurement setting of 200m on the multimeter registered between 10 and 15

    All measurements were taken several times both in the positive and negative by reversing the test leads orientation on the test piece. The test leads were short circuited in as close a proximity to the test piece as possible to establish no transient currents were being induced in the leads for the lead wires by the Dremel tool or the test peace. There was zero voltage and amperage registered from all measurement settings on the multimeter.

    The results of this experiment are very promising to say the least. The results of this prove the principle of design does in fact work and that the claims concerning this phenomenon are factual.

    I intend to perform more experiments in the near future or which I will post here if there is an interest in them. The success of this first proof of principle experiment has convinced me that it is worth while to invest in more elaborate experiments to establish the absolutes concerning this phenomenon. Hopefully I can glean enough information from my next experiments to put together a practical generator for common everyday uses.

    Please feel free to comment on any aspect of this issue. I am very interested in some intelligent interaction concerning this subject.
  5. Jun 25, 2005 #4
    New discovery

    Well as I seem to be the only one posting on this thread it doesn't seem like it would hurt to make an update on my progress.

    I conducted another experiment based on some assumptions I made regarding this unusual method of producing electricity. I am not prepared to go into the details of the design because I may be able to develop a patentable generator design from it.

    The experiment I conducted points to a new way of producing electricity mechanically. I understand there are skeptics among you who have heard this story before. But be assured you will hear of this in the very near future.

    There is a way to produce electricity without the losses associated with the backward torque that plagues current generator designs. This backward torque is believed to be unavoidable (it is for current designs) and as such accepted by most engineers as just another part of the equation in there work. Understand, it can be avoided and I have found a way around it. This fact will improve efficiency by leaps and bounds. The potential is huge!!!

    Now in the hopes that I may solicit a response from the community I would like to ask a few questions.

    1. Has anyone else out there experimented with the Faraday Disk design?
    2. Does anyone think that it is possible to produce a high voltage low amperage current based on the Faraday Disk principle?
    3. Would a system void of backward torque have the potential to change the way we produce electricity?

    Please post your comments and thoughts as it would be very helpful if a different perspective could be given.
  6. Jun 25, 2005 #5
    You have allready described how you have set the experiment up , plus there are many places to look up how it was done..
    yet you wont say the results of your experiment.?
  7. Jun 25, 2005 #6
    Um.... The results from my last experiment involved the use of a pair of 5 year old alnico magnets. I was able to measure at a very low rpm (standard cordless drill) a voltage of 1.0 to 1.2 at 200 m/v setting from the multimeter and an Amperage of 0.1 to 0.2 at 200 m/a . These measurements are a lot more reliable. It seems I did not make myself clear regarding my last experiment. I would like to establish that I did not use the faraday disk design for this last experiment. I made an assumption regarding my observations from the last experiment, designed a new experiment to prove my theory and it was successful. :) That is why I am so excited. I can produce a "practical" electrical current by moving the induction core with the induction magnets. By doing this I eliminate Back EMF associated with the changing magnetic field in the induction coil as it is at 100% (maximum field saturation) for a complete 360 degree rotation.

    I apologize for not being clearer.
  8. Jul 2, 2005 #7

    Where are the pictures? :)
  9. Jul 5, 2005 #8
    That "back EMF" can be thwarted is not in question. Rather, the question is how long?
    Generally, this only works through 1 cycle.
    That is, no anti-back-EMF schemes that I know of can infinitely cycle.
  10. Jul 10, 2005 #9
    Homopolar Generator - Physics Help and Math Help - Physics Forums. May as well meet the rest of the homopolar disk fraternity. :) The "Homopolar Handbook" by Thomas Valone is a very good reference and source of info on the (substantial) work of others in this field. There is no flouting of theory happening here, but there is no back EMF being produced either.
  11. Jul 10, 2005 #10
    High voltage, low amperage?? Nope.. Only the other way around.. huge current at fractional voltage - used in electroplating and a few industries like that. Seriously large units (10MW versions) have been built - these are used to fire up rail guns and the like. As a source of motive power or as a power generator.. not that anyone has come up with so far.. A few radical types like Bruce De Palma (who calls it his N-Machine) rekon they can.. but its not stopped traffic anywhere. https://www.physicsforums.com/showthread.php?t=9351&page=5
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