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Point out news stories, on the net or in mainstream media, related to polywell fusion.

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Joseph Chikva
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Postby Joseph Chikva » Fri Apr 20, 2012 3:27 am

hanelyp wrote:Looked up a stat on tokamaks for comparison. from http://www.toodlepip.com/tokamak/records.htm
Highest beta achieved in a tokamak (40%) START, UK

Most such devices operate at far lower beta. Compare to near 100% beta for a polywell.
Beta 40% is a Troyon limit. This is a theoretical limit. Actually TOKAMAKs run at 0.1 or even lower. But provide confinement time seconds and desired 1000 sec for ITER. Scaling "bigger device - longer confinement time" is proved for TOKAMAKs.

As mentioned above beta=1 or now your today's admission "near 1" (so, lower than 1) is based only on words of Dr. Nebel and contradicts to all we know today about plasma properties.
Recall that confinement time for Polywell is desired as I know as milliseconds order. And for providing Q>1 "milliseconds" mean necessity of much dense plasma than in TOKAMAKs (1E20 m^-3). And so, much stronger mag field. And so, much faster thermalization by alphas. Vicious circle.

Roger
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Postby Roger » Fri Apr 20, 2012 3:34 am

ladajo wrote:Bullshit flag thrown.

5 Yard penalty, defense. It is 3rd and 15.


Unsportsmanlike hand waving.
I like the p-B11 resonance peak at 50 KV acceleration. In2 years we'll know.

Joseph Chikva
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Postby Joseph Chikva » Fri Apr 20, 2012 3:40 am

Ivy Matt wrote:I might also note, for history's sake, that the one Talk-Polyweller who bothered to criticize your proposed confinement method was also a strong critic of the Polywell as well, albeit for different reasons. And now he's no longer around to argue with you.
Does not matter who criticizes. But matters sense he speaks.
Proposed by me method mainly is based on works of Gersh Budker who was genius well known around the world. And his method how to fight with transverse instabilities in beams (radiation friction) is accepted by everyone working in this branch.
Also I have shared the method with Stanley Humphreys Jr. who is leading expert in beam physics. He called method "interesting".
I have had invitations for taking participation in conferences from American and European physical societies.
Laughable "criticism" from man who does not know e.g. that two unidirectional currents attract each other or who admits at 100 keV collision energy reaction having significant cross section only at 50MeV.

ladajo
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Postby ladajo » Fri Apr 20, 2012 2:26 pm

KitemanSA wrote:
Joseph Chikva wrote:Instabilities grow up from fluxtuations and are fed from external energy. Even damping they are not dissapiaring but only may have acceptable scale. And because of it I do not believe you and for example Dr. Nebel whey you talk about possibility for Polywell to run at beta=1. "beta>1" means particles losses decresing number density.
And as you know well (I see) fusion power is proportional to square of number density.
Joe,
Would it make you happy if I said beta almost 1; a heck of a lot closer to 1 than any tok or other toroidal mag field "confinement scheme; so close to one as the really NOT MAKE ANY APPRECIABLE DIFFERENCE; but not EXACTLY 1?


Well, I would point out that Polywell as tested (by design in past models) passes through Beta=1 to blowout. There may be better control now as they seem to have moved away from gas puff to ion injection. But in any event, I do believe it would not be that hard to find the discussion I recall from either Nebel or Bussard talking about results and measurments as the machine "passes through Beta=1".
Polywell and Tokamak are apples and oranges in this regard.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

krenshala
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Postby krenshala » Fri Apr 20, 2012 2:32 pm

Joseph Chikva wrote:As mentioned above beta=1 or now your today's admission "near 1" (so, lower than 1) is based only on words of Dr. Nebel and contradicts to all we know today about plasma properties.

If my google-fu was stronger I'd be able to find that post on this forum where Dr B mentioned running beta up through 1 and blowing out the confinement shot after shot on early devices (WB4, 5 and 6, iirc). Of course, info directly from the person that actually ran the experiment would probably still not be enough for Joseph.

Joseph Chikva wrote:Recall that confinement time for Polywell is desired as I know as milliseconds order. And for providing Q>1 "milliseconds" mean necessity of much dense plasma than in TOKAMAKs (1E20 m^-3). And so, much stronger mag field. And so, much faster thermalization by alphas. Vicious circle.

If the alphas are leaving the confinement area, which we know they do/will, how are they able to thermalize the plasma? In a Tok, you want to trap them, if my understanding is correct, but in a polywell we want them to escape as fast as possible (preferably to a collection grid).

ladajo
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Postby ladajo » Fri Apr 20, 2012 2:49 pm

Joseph,
Once again, the simple concept difference between Polywell and Tokamak is:

Polywell:
Part 1: The unit is designed to confine Electrons Only. These e- are confined using magnetic fields. This is done to take advantage of e- very small mass and ease of control using magnetic fields.

Part 2: The Polywell unit once "confining" sufficient e-, then establishes a large negative potential at its center. This "Big Minus", as I have called it in the past, is then used to attract Ions. These Ions are not meant to be "confined". They are meant to oscillate in a chaotic manner through the central region of the 3D volume. The idea being that they will oscillate enough times, and with sufficient speed (energy) that statistically they will eventually have a collision and fuse mroe often than not before they escape the 3D volume. The products of the collision then may or may not have secondary collisions, but the end result is that they exit the 3D volume and the energy is harvested. Meanwhile, the "Big Minus" is maintained by make up e-(s) as determined by the e- loss rate.

Part 3: the idea of Beta=1 to 1 in a Polywel is fundamental to how it is supossed to operate. The idea is that we jam in and confine the maximum number of e- as possible given the existing magnetic field. That would be Beta=1. Pressure verse field is equal and balanced. To exceed it would obviously be a blow out. To not reach it would be operating the machine at lower possible efficiencies.

Tokamak: It wants to confine the whoel shebang with large magnets and volume. It does not want escapees. This is the big difference. Polywell does not actually seek full confinement of the fuel. It seeks only full as possible confinement of the e-. It then also seeks to allow the fuel (Ions) to have free access to each other without running into hardware before they fuse. If they Ion escapes before it fuses, that is ok. As long as enough of them that don't fuse and produce energy and products energy is harvested to sufficient levels compared to the energy spent to confine sufficient electrons to maintain a sufficient "big minus" potential to promote sufficient Ion oscillations and collisions. And the circle continues...

You argue that they have never reached Beta=1, and the machine can not do it, thus it can never be efficient enough to succeed. You do not calculate for the given 3D volume and field the maximum pressure possible to contain. You do not calculate the density and energy required to reach this pressure. You just hand wave and say it is not possible. This is based on your insistance to see it in only the Tokamak terms.

Meanwhile, the guys that have actually built and operated a number of devices, consistantly report that they have and do reach Beta=1 conditions, and even exceed them and suffer blow outs.

So, lets see, guys that actually do it, verses a hand waving guy that does not even do the math, but persists in with opinion based rhetoric. Hmmm, easy choice. I think until you can actually prove something other than functional jaw muscles and non-functioning brain, the guys actually doing the work win. Engage your brain, do some real background research, read the provided material, do some real analysis, post it, then point to it and argue your point.

Pffeeeep! Bullshit flag again on the ground, "Unsportsmanlike Hand-waving", 5 yards, loss of down, it is now 4th and 20.
Last edited by ladajo on Fri Apr 20, 2012 2:58 pm, edited 1 time in total.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)

What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

KitemanSA
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Postby KitemanSA » Fri Apr 20, 2012 2:51 pm

Joseph Chikva wrote:As mentioned above beta=1 or now your today's admission "near 1" (so, lower than 1) is based only on words of Dr. Nebel and contradicts to all we know today about plasma properties.
Actually, it is on the words of Dr. Bussard, Dr Nebel, Dr. Park (IIRC) Tom Ligon (?) and pretty much everyone who has ever worked with Polywell. Indeed, didn't the Sydney Group also agree with the beta~=1 condition?
So it would appear that what YOU know about plasma properties is either wrong, or immaterial.

Joseph Chikva
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Postby Joseph Chikva » Fri Apr 20, 2012 2:53 pm

ladajo wrote:Well, I would point out that Polywell as tested (by design in past models) passes through Beta=1 to blowout. There may be better control now as they seem to have moved away from gas puff to ion injection. But in any event, I do believe it would not be that hard to find the discussion I recall from either Nebel or Bussard talking about results and measurments as the machine "passes through Beta=1".
Polywell and Tokamak are apples and oranges in this regard.
Blowout can occur at number density much less than number corresponding to beta=1 in case of turbulence or/and instability. You can throw water from even partly filled swimming pool if generate strong enough waves.
And toks and polywell you and not me compare permanently. "This is not TOK where beta much less, Idiots throwing money on TOKs", etc. TOKAMAKs from the beginning being also very simple almost table-top machines gave much more fusion power than WB6. Now that is quite mature experiment and really give kilowatts of fusion power but could not achieve ignition "self-sufficient mode".
Best regards,

ladajo
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Postby ladajo » Fri Apr 20, 2012 2:59 pm

I forgot to type the part about how they are different above. It is in now.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)

What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

ladajo
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Postby ladajo » Fri Apr 20, 2012 3:07 pm

Joseph,
If (again I say this... tedious and repetative), you nothered to read up on the hostroy of Polywell. You would understand better why Dr. Bussard brought both Dr. Nebel and Parks on to the team.

Dr. Nebel and Parks both worked on POPS. Do you know what POPS is? Do you know why it is an important understanding and exeperience to bring to the Polywell concept? You talk about turbulance and instabilities.
You believe that these can bring the plasma in the Polywell to localized excessive plasma erngy levels that can then exceed the magnetic containment. You do not understand it is only trying to contain e-. It does not care if the Ions get outside the magnets. This is the whole point. It also even allows some of the e- to get outside the magnets, and provides a means for them to return inside. This was the "great insight" that lead to the design change and subsequent "success" of WB6.

Fusors are not Tokamaks.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)

What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

KitemanSA
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Postby KitemanSA » Fri Apr 20, 2012 3:33 pm

ladajo wrote:Joseph,
Once again, the simple concept difference between Polywell and Tokamak is:

Polywell:
Part 1: The unit is designed to confine Electrons Only. These e- are confined using magnetic fields. This is done to take advantage of e- very small mass and ease of control using magnetic fields.
I have a minor nit with this statement. The electrons are confined by the charge of the MaGrid but that confinement is enhanced GREATLY but the wiffleball field.

Of course, I don't KNOW that they are actually charging the WB8 like they did WB6, so I may be wrong about this!

KitemanSA
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Postby KitemanSA » Fri Apr 20, 2012 3:57 pm

Joseph Chikva wrote: Blowout can occur at number density much less than number corresponding to beta=1 in case of turbulence or/and instability. You can throw water from even partly filled swimming pool if generate strong enough waves.
Joe, for convex fields like Polywell, this is not true. You can suffer losses that way but such losses relieve the pressure and lower the beta slightly preventing blowout. As long as the material lost does not lead to Panschen arcing, the system heals and continues. The term as we are using it is like a balloon popping, blowing up, failing catestrophically; not burping a bit. By your analogy, blowout is like the sides of the pool collapsing due to having too much water to hold, SPLOOOSH!!

Since toks have concave fields, they may truly blow out at low beta, or they may use the term differently, equating blow-out and burping.

ladajo
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Postby ladajo » Fri Apr 20, 2012 4:06 pm

KitemanSA wrote:
ladajo wrote:Joseph,
Once again, the simple concept difference between Polywell and Tokamak is:

Polywell:
Part 1: The unit is designed to confine Electrons Only. These e- are confined using magnetic fields. This is done to take advantage of e- very small mass and ease of control using magnetic fields.
I have a minor nit with this statement. The electrons are confined by the charge of the MaGrid but that confinement is enhanced GREATLY but the wiffleball field.

Of course, I don't KNOW that they are actually charging the WB8 like they did WB6, so I may be wrong about this!


I see your point, but would add that the bulk of the work is by the field.

I will go back and read up on it again.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)

What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

Joseph Chikva
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Postby Joseph Chikva » Fri Apr 20, 2012 5:04 pm

ladajo wrote: Do you know what POPS is?
Yes, I do: Periodically Oscillated Plasma Sphere.

Joseph Chikva
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Postby Joseph Chikva » Fri Apr 20, 2012 5:18 pm

KitemanSA wrote:Since toks have concave fields, they may truly blow out at low beta, or they may use the term differently, equating blow-out and burping.
TOKAMAK having concave field always showed better confinement against Stellarators having convex field. As poloidal field in TOKAMAK decreases by increasing of radial coordinate, while in Stellarators all happens oppositely. Convex field had all mirror kind of machines. All them are forgotten now. Studying only Polywell history may be better if you get studied also what has been done in fusion research during past 60 years.
Good luck.


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