Polywell In Europe Raising Funds

[D Tibbets]

I don't know what the toroidal confinement surface efficiency is

Answer: as good as you can get by a Royal Mile. A toroid is the only closed surface geometry that can do it.

but R. Nebel has mentioned that the Wiffleball containment is ~ 1000 times better than mirror confinement.

Of course he would. He's got his sponsors to convince, and he also pretends he can't answer any questions, due to contract reasons, so he says anything he likes and knows his talk-polywell audience will suck it up. (Hence the term "suckers", I guess.) ...

The real question as I see it, is not wheather a pure toroid, is superior to a true sphere, but how close are the competing systems coming to this ideal.

Warning , if you read to far my arguments drift.

OK, I'll accept that a THEORETICAL toroid is a closed surface geometry that can completely confine a plasma. I think a THEORETICAL spherical geometry would also do it. The critical issue is how close you can come to those theoretical geomatries (and how much it costs). Tokamaks fall short due to instabilities, etc. The Pollywell Wiffle ball falls short in that it is not a perfect sphere. It has spikes with tiny holes(thanks to recirculation of the electrons). The holes are effectively much smaller for the ions due to the secondary potential well from the excess electrons. Also, the surface is mildly convex towards the center. But, this may actually be a benifit for several reasons. Small localized instabilities have to deform the surface more before it becomes concave and reenforces the instability. In this regard, the shape of the containing structure is not only important, but the robustness/ resistance to instabilities is also critical. And, as I speculated elsewhere, the curved surfaces of the Wiffleball leads to central deflection of electrons (and possibly ions if they reach that high) due to bounces off of multiple lobes. The first bounce will almost always be at a at a more obtuse angle to the center, but the second (or 3rd, 4th,etc) will eventually result in an angle more towards the center. The exception would be the lower energy electrons traveling almost parellel the Wiffleball surface would be more likely to be captured on a magnetic field line- I speculate that this low energy traped electron might travel along the field line and reach areas beyond the magrid , perhaps at a rate faster than the higher energy bouncing electrons can find a cusp hole. These low energy elrctrons could then be recirculated at original energy and radial vector. Either that or they are lost to the system by transport to the magnets.

You argue that the lack of aviable data implies lieing. This is a selfserving assumption on your part. A more honest conclusion on your part would be to say, I cannot judge the validity of his claimes without the data. You could then expand your viewpoint based on past expertise and experiance, but you need to always qualify it with well acepted arguments. A. Carlson has done this repeatedly, but the wiggle room aviable to counter arguments comes from possibly valid assertions of misused assumptions and resultant derivations.
The same applies to any debate (or argument) about cold fusion, global warming, economic theory, quantum theory, etc. The only real differences
are the skills of the debaters, the reproducity of the data, and the demonstrated acuracies of the predictions. The discussion can be further confused by different basic assumptions and systems. eg- magnetic confinement vs electrostatic confinement, static assumptions vs dynamic assumptions, Maxwellian vs non Maxwellian assumptions, etc. There are two significant trump cards. The King of established thoery, and the Ace of data. Even then interprtation can deviate.

Dan Tibbets

[chrismb]

You argue that the lack of aviable data implies lieing.

I certainly do not argue that anyone is lying. But I would agree that I think a lack of data followed by grandiose claims is self-delusional. I don't think the self-delusional are liers, per se, I'm not able to claim that.

The real question as I see it, is not wheather a pure toroid, is superior to a true sphere, but how close are the competing systems coming to this ideal.

OK, I'll accept that a THEORETICAL toroid is a closed surface geometry that can completely confine a plasma. I think a THEORETICAL spherical geometry would also do it.

I'm not sure you understand. There is NO such thing as a theoretical spherical geometry, whereas a toroidal geometry is a reality. The issue with a tokamak is that the toroid is unstable - the magnetic field on the inside is bigger than the outside so it pushes the plasma out. The confininf magnetic surface then becomes not a toroid! But it can, and does, start out that way. It has no holes.

The idea that a spherical geometry with holes could compete is not a sound argument. You might reasonably say "Ah! but the toroidal geometry has not yet been demonstrated as stable" to which I would ask "...and the wiffleball HAS???!!!!".

A tokamak is like a bucket made out of paper - put too much in and it collapses. As far as we know, a wiffleball is a bucket made out of paper with holes in it, and 25 YEARS of research has shown no contest to that analogy. This is no small time in which to have shown some progress by now.

Remember; Bussard has several 'fusion' related patents. They're all based on toroidal schemes, except for the one 'wiffleball' fantasy.

[Stoney3K]

Not to be interrupting here, gentlemen, but can we go back to the fundraising in Europe matter? Discussion of confinement surfaces is perfectly valid on another part of the boards.

[D Tibbets]

Chrismb, aight if you don't like my THEORETICAL adjative, use imaginary instead. You yorself admit that the Tokamak does not form a stable toroid- thus my argument that the issue is how close you can come to that condition at an acceptable energy cost. And before you argue that an imaginary magnetic sphere is impossible, remember that it only serves as an impossible goal , the question is not wheather you can realize this imposibility, but if you can come close enough to it to exceed some nessisary condition.

Also, keep in mind that the goals ot the systems are different. In the Tokamak you try to pump in energy faster than it leaks out so that you can reach ignition conditions, Then you worry about maintaining and extending those conditions so tht you can get usefull power out. In the Polywell you don't worry about ignition, and if assumptions are true (they have to be for the Polywell to have a chance to work) then the poor energy costs of maintaining a thermalized plasma at fusion conditions is relaxed- ie: The Polywell can leak faster but still have an advantage in the energy balance equation.

I would modify your bucket analogy. The Tokamak would be a bucket made out of thin paper that leaks. The Polywell is a paper bucket that is painted with varnish so it leaks alot less. Then you punch a bunch of tiny holes in the Polywell bucket. So which leaks less, a leaky paper bucket, or the varnished paper bucket with holes. It all depends on the particulars.
Also consider the size of the bucket. If the Polywell has a much higher energy density than the Tokamak, the bucket is much smaller, so the leaking of the bucket per unit area could be much larger but still lose less in proportion to the power output. Add to this (you probably would need to to take advantage of my prevous sentance) the 'semipermiable' membranes that cover the holes in the Polywell bucket- electrons leak out much easier than the ions. Then add the benifits that 9/10 electrons that leak out get pumped back in via a recirculating pump that requires almost no energy. The 'leakyness' of the Polywell bucket can be conciderably greater, but still reach net power easier due to advantages in energy density (bucket size), nonthermalized conditions, cheap recirculation, etc.
Another concideration that might be useful in the bucket analogy- the Tokamak is vunerable to instabilities that can be compared to water slopping over the rim of the bucket, but the Polywell bucket has a lid on it( or conversly, it has less energetic instabilities that do not reach the rim of the bucket)...

ps: The confinement time for an electron in WB6 was ~ 0.25 seconds by my calculation. Recirculation would increase that to ~ 2.5 seconds. Ion confinement time is presumeably much longer. What is the particle containment time in a Tokemak reactor like JET?
[EDIT]- err, the above numbers should bemilliseconds, not seconds.

Dan Tibbets

[JohnSmith]

@D Tibbets
Just a note about toroidal/spherical confinement. A sphere cannot confine plasma without leaks.

[alexjrgreen]

@D Tibbets
Just a note about toroidal/spherical confinement. A sphere cannot confine plasma without leaks.

A wiffleball isn't just a sphere. It's a sphere with holes.

The six central cusps allow electrons (and some ions) to leave in well formed jets, pass through the magrid and oscillate back to the wiffleball.

The hairy ball theorem seems to be resolved by the ends of the jets resembling a Klein bottle.

[chrismb]

@D Tibbets
Just a note about toroidal/spherical confinement. A sphere cannot confine plasma without leaks.

A wiffleball isn't just a sphere. It's a sphere with holes.

The six central cusps allow electrons (and some ions) to leave in well formed jets, pass through the magrid and oscillate back to the wiffleball.

The hairy ball theorem seems to be resolved by the ends of the jets resembling a Klein bottle.

So what you're trying to argue for is that a Polywell is actually just N tokamaks all intersecting at a point. You do understand that's pretty much what you're suggesting, topologically speaking? Think about it; each magrid coil would be the primary transformer coil of a tokamak, with a current flow passing around it. Now wonder whether, given that configuration, we're not going to see 'plasma' [viz, ions in a state of recombination] being routed through those magrid coils?

Oh dear, perhaps we now have [2N]! ways for instabilities in a Polywell! Is this really the claim you want to go for??

[alexjrgreen]

Is this really the claim you want to go for??

It's the only way I can resolve the statements from Rick and Art.

So, yes.

[D Tibbets]

I'm out of my depth with these mathmatical derivations. From a macroscopic, pratical world standpoint, they seem mostly trivial. I can see the Hairy theorum as possibly being an explaination for Stars always having some angular momentum even if the cloud it condensed from was a perfectily spherical shape (or at least as spherical as the hairy theorum allowed) with perfectly motionless mo;ecules.
But, in terms of most situations I don't see it as being significant. Certainly it can be ignored when you talk about the air inside a pingball ball. As I said above we are not talking about perfect toroids, or a (perhaps not quite) perfect sphere, but how close you can come to these conditions so that some required proformance can be reached.
Ialso, don't follow CB's argument about overlaping and intertwining toroidal fields. The magnetic fields of any geometry do two things (my understanding). They deflect moving charged barticles along field lines, or they deflect them at a different angle dependant on velocity and incident angle. Two torus shaped magnets opposing each other produces a containment effect well understod in mirror machines. Expanding the opposing magnets into three planes also produce well understood containments. Up to this point the Polywell is entirely mundane. The formation of a wiffleball effect is less understood, but I've not seen, and probably could not understand, explainations for its imposibility. From my limited knowledge, it seems to follow from the magnetic field interactions, and from accepted charged partical pressures. Questions of how much the cusps are pinched in this process is debated. The recirculation of electrons also seem straightforward. The dynamics/ thermalization times, etc are also debated, but do not apply to the containment except for the tremendously important recirculation that effectively improves condinement times for the electrons and also perhaps slows the thermalization time of the total electron population.

What I'm trying to say is that sometime ambigous math can confuse more than help. A bullet could be proven mathmatically to never reach it's target. An ion could be argued to spend an eternity at the top of a potential well. Or another way of looking at it is: If it looks like a Duck and quacks like a Duck, then it probably is a Duck.

Concerning actual confinement performance of a good, but real toroidlal setup like in a Tokamac versus a Polywell setup, it is obous that neither are perfect containment scheams, not even close. Again, the question is which is better within the required limits of their respective needs.
As a comparison, concider that the Polywell only attempts to confine the electrons, the ions are irrelivant for this discussion. I assign this advantagous condition a factor of 10X. Recirculation of the electrons gives an addition factor of 10X. Assumeing that everything else was equivalent (which it is not, I assume the much higher proposed energy density makes a big differencel) the Polywell basic containment would only need to be 1 percent as good as the Tokamak containment that does not have recirculation and needs to confine ions as well as electrons. Arguments about the effective electrostatic containment of the ions in the polywell can modify this ratio, but again, it depends on the extent of the various elements. There are no absolutes.

The recognition of these multiple variabls and their interplay, leads to the desire to study these questions in detail, thus the European initiative (this assertion puts my post back on target for this thread (at least by a tiny amount )).

Dan Tibbets

[alexjrgreen]

The Hairy Ball Theorem is topological, so it's not affected by how round the ball is.

[vernes]

Not to be interrupting here, gentlemen, but can we go back to the fundraising in Europe matter? Discussion of confinement surfaces is perfectly valid on another part of the boards.

I agree

[vernes]

Hum, seems that the Netherlands starts to be quite a focal point here. I'm curious as to the number of Dutchies on this board...

Maybe a poll in General forum?

[TallDave]

The real question as I see it, is not wheather a pure toroid, is superior to a true sphere, but how close are the competing systems coming to this ideal.

No, the real question is "who cares?" since they aren't confining the same thing.

A tokamak is like a bucket made out of paper - put too much in and it collapses. As far as we know, a wiffleball is a bucket made out of paper with holes in it,

You're missing the most salient point: in a Polywell the force of gravity pulling on the water is counteracted by another force, so less water is spilled.

This is no small time in which to have shown some progress by now.

It's a good thing Polywells have a 100MW reactor design. That puts them... exactly as far as tokamaks. Except Polywells cost 100 times less and can be done 20 years sooner.

[KitemanSA]

Just a note about toroidal/spherical confinement. A sphere cannot confine plasma without leaks.

Well, the sun leaks, so I guess you are right, but I suspect you meant that a "spherical MAGNET" can't confine plasma...

By the by, Polywell isn't a spherical magnetic containment system for plasma.

[Art Carlson]

Just a note about toroidal/spherical confinement. A sphere cannot confine plasma without leaks.

Well, the sun leaks, so I guess you are right, but I suspect you meant that a "spherical MAGNET" can't confine plasma...

By the by, Polywell isn't a spherical magnetic containment system for plasma.

So you would be happy if we said "A spherical MAGNET cannot confine electrons without leaks"?