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  • #61
    Hi Dean,

    I was wondering if you could either post a diagram or tell us what size magnets and strengths that are used in your track (and rotor, if you haven't done so already--I have to go back and read the earlier posts). Thanks!

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    • #62
      magnets

      Shamus, Yes - I'll try to get the sizes and strengths posted this evening.

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      • #63
        magnet specifics...

        PMsizes2a.jpgShamus, et al – the beginning of magnet sizes and strengths. More to follow.

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        • #64
          more magnet specifcs...

          Rotor and polarities. The PMs inside the rotor in this model are four 2" long 1/2" N50 magnets. Two 2" together forming one four inch length for each end of the rotor. Matching polarity outside ends. PMs flush up to ends, gap in center (about 3"). Some rotors were tested with a third group of PMs in the center.

          The brass is a very thin wall, snug fit for PMs as well. I tested brass and aluminum rotors, both worked, brass peformed better. I also tested copper which was very poor. I tested steel, also very poor. Plastic does not work at all. More to come...PMsize3a.jpg

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          • #65
            scaling down is possible?

            Hi Dean,

            I wonder if you have pondered on making the (basic) setup that could still work in much the same way, in a smaller overall size? I guess torque will probably be way less than it is now with your sizes shown but certainly cheaper.
            For I guess even the rotary version you already showed in a picture can easily come out as 500-700 USD? (just the price for the magnets)
            And when a smaller scale could also work (albeit with less torque) it would cost perhaps 100-200 USD? Just pondering on this possibility and if the scaling down is feasable then perhaps using some air core coils, positioned at strategical places as electromagnets, the torque could be a bit increased from the generated output electric energy (say by using a normal generator as driven by this smaller sized magnet motor).
            No I do not wish to envision this so complex, just some brainstorming, lol

            Thanks, Gyula

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            • #66
              An IMPORTANT early discovery…

              Early in the testing of this design, long before I understood “why things were occurring, I became concerned about friction and wear. The wheeled surface of the rotor and the track surface was the concern. I applied a Teflon plastic edge to the aluminum rail. Only to discover the rotor NO longer moved. It locked on the very first PM.

              It was at this point I discovered that the physical conductivity of the brass and aluminum was necessary to work (plastic insulated the electrical connection). It started me on the path of discovery that the rail was in fact a stator, and the system was dependant on the multiple secondary magnetic fields that were induced fromm movement. A Game Changer for me.
              Green Energy 211

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              • #67
                Smaller works...

                Gyula, I see no reason that a smaller format would not work. The smallest I have built was about 6” wide (150mm) by 24” long (600mm). Worked just fine. You might try narrower as well, but I wouldn’t go any shorter. The reason I built them larger, and kept going longer, was for testing. I wanted to rule out momentum. Of course the first time the rotor did a 180 degree one me, I was no longer concerned. I’d like to build a larger one now, for testing. Say, to the next town?

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                • #68
                  more polarities

                  There are six re-occuring sets in a "gate".PMsize3b.jpg

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                  • #69
                    note on magnet sizes and insight on brass...

                    In this wider and longer track, you can see a third 1" x 1" N50 was added to both sides. As well as other extensions in between. Also, the brass has not been installed yet, and gives a clearer picture of smaller PM layouts.

                    I've never fully understood the actions of the brass, it's clear it acts as a conductor. Yet it also adds a, "homogenous" quality to the magnetic field. A bit hard to explain - it seemed to make things more "fluid", a blending of the fields. Even with stop motion, it's NOT possible to detect the rotor moving from gate to gate - it just "flows" straight through. The "hand-offs" (if they exist) are elusive.
                    Attached Files

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                    • #70
                      Brass

                      For non-ferrous metals such as copper, brass, aluminum etc., the permeability is the same as that of "free space", the relative permeability is ONE. However, I would imagine secondary eddy currents could form within the material. Traditionally though, these forces usually work against you.

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                      • #71
                        Dean,

                        If I understand this correctly, then there are magnets inside the brass tubes per your illustrations. Is this correct? If this is the case, then I think the Faraday Ice Pail effect has a role in this also. Also, I would like to draw your attention to this article on "Electrostatic Charges in a V x B field: The Faraday Disc and the Rotating Sphere".

                        Below is a snippet found in the above publication on electrostatic charges in a V x B field.

                        1. Introduction

                        Imagine a body that moves at velocity v in a region where there exist an electric field E and a magnetic field B. Then an electric charge Q inside the body feels a force Q (E + v x B). Thus, inside the moving body, the v x B field acts like the electric field of a distributed source. We are concerned here with conducting media that move in magnetic fields. We shall see that they carry electrostatic charges whose field is just as important as v x B. Indeed, there are many cases where the two fields cancel each other exactly at every point. The Faraday disk and a conducting sphere rotating in a magnetic field will serve as examples, but this little known effect plays a fundamental role in magnetohydrodynamics.

                        2. Electrostatic charges in v x B fields

                        It is well known that conductors do not support an electric space charge; any extra charge deposited inside moves out to the periphery almost instantaneously (Lorrain et al 1988, p 75). However, few physicists realise that conductors do carry an electric space charge when subjected to a v x B field whose divergence is not equal to zero. If the conductor is isolated, then it also carries a compensating surface charge.

                        What are your thoughts on this?

                        Surface Charge.
                        Space Charge.

                        Thanks,

                        GB

                        Comment


                        • #72
                          Space Charge and Surface Charge

                          Hi GB, Excellent find and references GB. It certainly seems the Ice Pail experiment may explain the behavior of the “brass”. For other’s benefit: “Faraday's ice pail experiment is a simple electrostatics experiment performed by British scientist Michael Faraday that demonstrates the effect of electrostatic induction on a conducting container. For a container, Faraday used a metal pail made to hold ice, which gave the experiment its name.

                          The experiment shows that an electric charge enclosed inside a conducting shell induces an equal charge on the shell, and that in an electrically conducting body, the charge resides entirely on the surface. It also demonstrates the principles behind electromagnetic shielding such as employed in the Faraday cage. The ice pail experiment was the first precise quantitative experiment on electrostatic charge. It is still used today in lecture demonstrations and physics laboratory courses to teach the principles of electrostatics.”

                          Yes, I think that both Surface Charge and Space Charge may apply. Although, I also think it may take some time to digest the rest of the literature here you have uncovered. What is your understanding of the reference to “time dependent” in the following statement?

                          “…Recalling now that, an isolated moving conductor, there are no induced currents if the curl of the current density is zero. This equation shows there are induced currents in an isolated moving conductor only if the magnetic induction in the reference frame of the conductor is time dependent. This is in the agreement with the equations.

                          The space charge density is the same in the two reference frames if the azimuthal current results only from the motion of the space charge.”

                          Note: I have discovered that the gentlemen that did this follow-up research had died a few years ago. However, his son had collaborated on several of his published works. I’m attempting to track him down and see if they ever took this beyond the equations?

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                          • #73
                            Lorrain's work

                            GB, I think it's important to realize that much of Paul Lorrain's work is with "fluid magnetics". However, the theory and many of the equations seem to apply. Interesting, I have thought of what was occuring to the simular behavior of the many magnetic fluid layers we have in our planet.

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                            • #74
                              Originally posted by Dean2 View Post
                              What is your understanding of the reference to “time dependent” in the following statement?

                              “…Recalling now that, an isolated moving conductor, there are no induced currents if the curl of the current density is zero. This equation shows there are induced currents in an isolated moving conductor only if the magnetic induction in the reference frame of the conductor is time dependent. This is in the agreement with the equations.

                              "Time dependent" would be a changing field over time, either in strength or direction. I hope I got this right. I probably should re-read that publication again, because it's been awhile, and I haven't fully digested that entire article either. Please keep us up-to-date on what you find in regards to if there was any follow up work done beyond those equations. You work fast. Thanks for the information and for helping us to understand how your device is constructed with all of those images you have provided. I can see you take pride in your work.

                              GB

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                              • #75
                                The below statement found on page 95 is interesting.

                                "Now, in our isolated rotating conductor, currents can only flow around closed circuits. Then the line integral of J around any closed circuit is equal to zero and there are no induced currents. In this instance, the field of the electrostatic charges cancels the vxB field exactly at every point. This is not a new result (van Blade 1984), but it is important for the following reason. Since there are no induced currents in the rotating conductor, the magnetic field is not disturbed and the lines of B are not dragged along by the moving conductor, as one would expect from Alfven’s ‘theorem’ (Alfven and Faltham-mar 1963). Another paper will discuss this ‘theorem’ at some length." I wished i had these other papers. The current paper we are referencing now cost $35 in the peer review journals. It was freely available for download at one time, but is no longer (at least the last time I checked).

                                GB

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