Search found 3161 matches

by chrismb
Mon Dec 15, 2008 8:48 am
Forum: Theory
Topic: Total ion flux in a Polywell - disruption to magnetic field?
Replies: 38
Views: 11691

The ion currents are mostly radial, Is that a statement of fact, experimental measure, guess-work, or other? Is there any supporting evidence to this claim, or does it represent an intuitive assumption? If you had never actually seen water go down a plug hole, you might think it would go 'straight-...
by chrismb
Mon Dec 15, 2008 8:35 am
Forum: Theory
Topic: How do protons make it into the centre?
Replies: 11
Views: 4437

The words are fine words, but do they make sense. What is meant by 'pushing the magnetic field' out? Are we saying that there are 1T magnetic surfaces surrounding the electrons in the centre, then, just a few mm out, suddenly 'puff' - nothing, no more magnetic field at all?? You can't do that if you...
by chrismb
Sun Dec 14, 2008 8:37 pm
Forum: Theory
Topic: A few questions on Polywell facts and figures.
Replies: 63
Views: 18156

A few questions on Polywell facts and figures.

May I please clarify a few bits of data: In the Polywell SCIF table, it suggests that the 'fusion reactor' particle density will be 2E20/m3 outside the core. Is this meant to mean that there would be 2E20 ions in that region, or is it also including/anticipating the neutral content of the device? If...
by chrismb
Sun Dec 14, 2008 7:59 pm
Forum: Theory
Topic: How do protons make it into the centre?
Replies: 11
Views: 4437

If we take the 'parallel plate magnetron' condition, Vcrit = [q.B^2.s^2]/2m, and presume our Vcrit is the 110kV well between 'anode' and 'cathode' surface potentials of 1m separation (s), then we get B = 0.05T as the minimum field required to arrest the motion of a proton. So the presumption is that...
by chrismb
Sun Dec 14, 2008 6:24 pm
Forum: Theory
Topic: How do protons make it into the centre?
Replies: 11
Views: 4437

How do protons make it into the centre?

Maybe I am completely missing something, but as I understand it, the argument is that the 1T field confines the central core electrons, but the protons aren't affected because they are too massive. But surely the gyroradius (=mv/qb) of a proton at, say, 550keV (= 10Mm/s) in a 1T field is 0.01m (1 cm...
by chrismb
Sun Dec 14, 2008 5:47 pm
Forum: Theory
Topic: Total ion flux in a Polywell - disruption to magnetic field?
Replies: 38
Views: 11691

OK. I see your point. However if you get bunching and oscillations it might not actually work that way. Yes. That's the point I am trying to get to. As all this huge flux of ions run into the centre, they're not all going to be coming in perfectly symmetrical. Is the ball of electrons perfectly sym...
by chrismb
Sun Dec 14, 2008 5:31 pm
Forum: Theory
Topic: The Brillouin limit.
Replies: 11
Views: 6938

So, presumably, there are intended to be no 'slow' ions in the central electron core, else they would recombine, and we are looking at balancing the total population of ions that happen to be passing through the core at any given moment to within this 5E18 Brillouin limit. But this still leaves all ...
by chrismb
Sun Dec 14, 2008 9:17 am
Forum: Theory
Topic: Total ion flux in a Polywell - disruption to magnetic field?
Replies: 38
Views: 11691

Chris, IIRC huge circulating currents were predicted for Polywell. I'd have to look up the number but I believe they were in the range you estimated. So, at what ion flux does magnetic field disruption occur? There must be some rate at which this happens such that it becomes significant in comparis...
by chrismb
Sun Dec 14, 2008 7:49 am
Forum: Theory
Topic: The Brillouin limit.
Replies: 11
Views: 6938

The Brillouin limit.

The Brillouin limit defines the maximum number of particles in non-neutrality conditions, viz. Polywell's central core of electrons. {L Brillouin, Phys. Rev. 67, 260 (1945)} This is n=B2/(2umc2) [n:particle count, B: mag field, u:permeability] For a 1T field, as per the 'fusion reactor' in http://ww...
by chrismb
Sun Dec 14, 2008 7:28 am
Forum: Theory
Topic: Total ion flux in a Polywell - disruption to magnetic field?
Replies: 38
Views: 11691

Ah, here we go: http://www.askmar.com/Fusion_files/Polywell%20Ion%20Focus%20Concept.pdf Table 1 anticipates core density of 2e24/m^-3 in a fusion reactor. But this paper is from 1992 (albeit updated with pics in 2007), so if anyone has something more recent please share. Where did I get 1E19 from? ...
by chrismb
Sun Dec 14, 2008 12:32 am
Forum: Theory
Topic: Total ion flux in a Polywell - disruption to magnetic field?
Replies: 38
Views: 11691

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

Hi. I thought I'd pop in to talk-polywell.org forum, off from the fusor.net site, to see if I can discuss a few issues of [im-]practicality I am curious over. Consider the proton-boron collision at 550keV = 1.2barns. And the closing velocity is 12/11*a proton at 550keV = ~11Mm/s. Let's say that the ...