Talk-Polywell.org

We seem to have a good idea of the structure of the E and B fields outwith the wiffleball, but what about the structure inside? I hope we can build an understanding of the structure of these fields in the plasma or in the skin because it is possible that this structure provides an additional mechani...

Thank you for your replies. I will take time to digest them.

I find myself being very puzzled by physicists, who I am sure know much more about plasmas than I do, making statements that are in total conflict with physics that I understand. Please forgive me and put me right if the following is nonsense, but knowing how easy it is for familiarity with a comple...

The forces on a Magrid coil can be calculated as being due to the sum of the the magnetic fields due to the other five coils plus the sum of the fields due to all the image coils. This calculation can be done without knowledge of the energy and total number of electrons that have been introduced to ...

93143: In due course of time, experiments, measurements and theoretical developments will tell. In the meantime the image structure will give a more illuminating picture than a sphere with no internal magnetic field, because it is the internal magnetic field that "pushes back" the field of the Magrid.

93143, I can't let you get away with that! Icarus, who originally posted the image idea did so to specifically expose the internal structure of the wiffleball and the features you see are real and physical. I concede that the current solutions with a perfectly spherical wiffleball are simplistic, bu...

Art: The image technique is a useful qualitative and quantitative tool. which in this case has given a useful insight into a probable structure for the fields inside the wiffleball. It is most unlikely to be a correct solution as it stands, but it is capable of being usefully elaborated and it has a...

Rion: That is a good start. I am thinking of a routine maintenance situation after, say, a year long run, when there would likely be a substantial amount of condensed boron dust between the Magrid and the vacuum chamber wall. Would we be able to get a reactive nitrogen plasma to form in those region...

A possible solution to the problem of clearing up potentially explosive self igniting boron dust could be to oxidise it slowly, or otherwise react with it, by very slowly introducing oxygen or some other suitable reactant into the inert gas. Has anyone the chemical knowledge to comment. If not, can ...

I may have a solution to my problem.

A -ve potential (relative to the Magrid) trap grid, in the shadow of the Magrid, which I see as probably being necessary anyway for the p-11B system.

I see a possible disadvantage with the elongated coil cross section. It will require careful design to ensure that the Efield gradients in the corner cusps are not so small and so long that low kinetic energy electrons get stuck in the region of the magrid. Obviously circular cross section coils wil...

It appears to me that the effects of the B field within the wiffleball are being ignored in the discussion of electron losses. If one looks at Indrek's visualisations of the field lines using the method of images and based on a perfectly spherical wiffleball, it is apparent that the Bfield WITHIN th...

Between the adjacent coils the field lines are straight, radial and densely packed. The fields are stronger than anywhere else, see Indrek's linear plots as opposed to logarithmic. I envisage a radially elongated coil cross section with almost flat faces where the coils are adjacent. So far nobody h...

Despite the fact that the coil cans are supposed to be conformal, there must be some flux surfaces which intersect the coils, and from which electrons are lost once they diffuse far enough cross-field. The coil cans will be quite thick in the real thing because they have to contain the cooling syst...

I am beginning to think that a large portion of the electrons in the well circulate in the image coils (probably a fuzzy version). It could be that there are an infinite number of infinitessimally spaced image coils along radial lines as well as a similar circumferential distribution caused by a non...