Total ion flux in a Polywell - disruption to magnetic field?

[chrismb]

chris,

If you study fusor design the shape and openings of the grid don't seem to have much effect on star formation.

Not sure I understand you. The star mode beams pass through the openings. I've never seen a star mode pass through anything but a grid opening. They don't pass through the grid itself. Sorry, I realise that sounds flippant but 'which' openings it passes through and whether it is exactly aligned to the centre is just down to the vagaries of the irregular electric field that the grid forms. But a relationship between beam an grid opening is both obvious and expected, no?

Your faith that self-organisation can occurs in a Polywell appears to be based on the appearance of these star beams in a fusor. Am I understanding you correctly? You say "perhaps we could start from what we SEE"... fine. What do you see in the titanium needle cathode fusor? No grid and no beams. Do you think this could suggest the beams are just down to the grid, or do you seek a more complicated answer? Remember Occam's razor! Why do you seek a more complex answer? Is there some other observation of Polywell or fusor that leads you to seek more?

[MSimon]

You have to factor in the RF generation at discrete frequencies. That would tend to indicate oscillating beams. Although I admit it is not definitive at this point.

And yes the beams would have to come through grid openings. But not all openings have beams.

All this requires more study. Fusors would be more than adequate for the task. Unfortunately because they will not lead directly to net energy they have been under researched.

Dr. Mike is in the process of building a fusor with some of these ends in mind.

In fact for these studies fusion is not necessary and a heavy noble gas such as argon or xenon might prove superior due to the lower frequencies that a heavier mass would produce. In theory. If the frequencies are e/m related. Of course full ionization is harder with the higher atomic numbers.

[KitemanSA]

Is the ball of electrons perfectly symmetrical? I understand it has various cusps, so clearly not.

As I understand it, this is one reason for WB8, the dodec polywell. It is supposed to help check out the effect of having a less quasi, more spherical magnetic field.

[KitemanSA]

This is one of the reasons I don't think an octa-coil will work. It's not spherically symmetric.
But it will be interesting to test that!

You've said this before, but I don't see why. If instead of putting the coils on the square part of the rectified cube, you put them on the triangular parts, the core would remain at least as spherical. That is the octo-coil. It is just that with two more of the same size coils (as I've suggested as an interim step to WB8) you would get a larger sphere. There would be a bit of scaling data there for almost no cost whatever.

[KitemanSA]

The ion currents are mostly radial,

Is that a statement of fact, experimental measure, guess-work, or other?

I look at it as "other". WB6 seemed to work as expected, which suggests (but does not prove) that the theoretical construct, including ion currents being mostly radial, are probably near true.
As I understand it, Dr. B was convinced that off radial (and differential radial) motions of ion flux were annealed out at the top edge of the well, retaining the radial, non-Maxwellian character of the plasma.

[MSimon]

Chris,

In a fusor the beams pass through the holes. Not all the holes have beams.

[MSimon]

http://www.fusor.net/board/index.php?bn=fusor_images



Note that there seems to be preferred directions.

[chrismb]

Chris,

In a fusor the beams pass through the holes. Not all the holes have beams.

It's a good and interesting point and I do not pretend to have a known answer other than the electric fields are not uniform and also that once a beam starts up it will, specifically, ionise more material along ITS path and not another path.

The 'beam' is therefore self-ionising in that way - ions will run in from the point of their creation as it is formed, simply, where the beam is. The beams energy is lost to ionising event, and is therefore likely to be self-sustaining. Why selectively on particular beam directions? Because once a beam forms it will also generate an excess of electrons through which there are conductance losses, thus 'draining' the input power to feed the otherwise as yet unformed beams, and specifically in the direction of that beam, thus there will be a cascade of electrons in the first beam. More that one beam? Then they are better balanced than between another alterantive beam line.

Consider it as if it were a 'slow' form of lightning/HV tracking. These pick preferred routes also, and once the tracks are active, so they pull down all the current for themselves and surpress the power supply.

The experimenter might see a couple of beams form and cut off the current at that point. if the power had been upped, maybe more beams would form. Perhaps your question might equally be 'why do fusor experimenters only turn up the power to get one or two beams', the answer then being because they don't want ot burn the device out. So maybe we don't even actually understand the question well enough!!

Of course, you may be right, there may be a more complex reason that this that may touch on self-organisation. There are a lot of maybe-s between that and a $2M a year justification looking for it, just to prove a hunch.

I think you may choose that my explanation is insufficient because you are hoping for something more interesting than this - and that is you perogative to think like this on your own time and for your own interest, nothing wrong with that at all and good for you. But just be careful about the balance of evidence versus wishful thinking if you are trying to progress towards an 'optimum' understanding. I accept what you are saying as a possibility, sure. Does the evidence support further invesitgation based on your hunch..I am clearly less convinced than you are, but if it's your money then go for it!

best regards,

Chris MB.

[MSimon]

After looking into it some more I think the preferred directions are an artifact of the experimental set up.

I'm going to look into it more deeply before I make any further definite statements.