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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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Post by Joseph Chikva »

KitemanSA wrote:
Joseph Chikva wrote:
KitemanSA wrote: Then again, where is the thread that gives 1/r(minor)?
Of what?
It was your statement.
I asked "of what" only for clarifying. Apples, oranges or what? :)
As not only mine but also Bio-Savart's statement is that magnetic field (poloidal field for toroidal geometry) of straight current (toroidal current) is inversely proportional to radius (minor radius). Learn very basics.

D Tibbets
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Post by D Tibbets »

tomclarke wrote:........


Of course, I believe that plasma studies are incredibly complex, and that there is not good evidence that polywell will be immune from plasma instability issues at high beta. Perhaps there will be clear experimental data from EMC2.
I am satisfied that that stable high Beta has been achieved. This goes hand in hand with Wiffleball formation. Admittedly my opinion is based on indirect evidence. The photo multiplier tests done by Bussard, etel and the alternate method used by Nebel, etel that showed the density increase consistent with this effect. What I do not know is the relative duration of these conditions. Have they maintained them long enough? The WB6 high beta maintenanced at ~ 0.25 milliseconds., and was terminated not by magnetic confinement instabilities , but by arcing considerations. Are macro instability in the magnetic confinement of electrons on time scales of less than or more than fractions of a millisecond? When Bussard said the physics was solved, I'm guessing the necessary time scales were included. Either that, or there was an assumption that the convex magnetic fields prevented this possible instability.

PS: After doing a modest GOOGLE search on convex magnetic fields and macro instabilities, I saw some hints that these fields were stable. Certainly I saw no mention that they were unstable like concave fields. I suspect definitive studies were undertaken prior to the internet.

Dan Tibbets
To error is human... and I'm very human.

Joseph Chikva
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Post by Joseph Chikva »

D Tibbets wrote:I am satisfied that that stable high Beta has been achieved.
Link? About "achived".
D Tibbets wrote:PS: After doing a modest GOOGLE search on convex magnetic fields and macro instabilities, I saw some hints that these fields were stable. Certainly I saw no mention that they were unstable like concave fields. I suspect definitive studies were undertaken prior to the internet.
All mirror machines had convex fields. But where are they? Didn't they sink into oblivion?

KitemanSA
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Post by KitemanSA »

Joseph Chikva wrote: All mirror machines had convex fields. But where are they? Didn't they sink into oblivion?
Too leaky. Polywell shouldn't be NEARLY so leaky.

ladajo
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Post by ladajo »

Kite,
That would require Joseph to understand the fundamental points of why Polywell. I think he still doesn't get it.
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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Post by KitemanSA »

Joseph Chikva wrote: As not only mine but also Bio-Savart's statement is that magnetic field (poloidal field for toroidal geometry) of straight current (toroidal current) is inversely proportional to radius (minor radius). Learn very basics.
So you are implying that the current only runs at the center of the minor diameter so that the poloidal field diminishes at 1/r? An infinitesimal thread of current, zero units wide?

What happened to the significant toroidal field? You said that was 1/r too. How can it be? It SHOULD be uniform with minor r if the solenoid was straight. But the solenoid is bent into a circle which makes the field at the inner end of the minor diameter higher than at the outer end. Where is the 1/r there?

RAGE RAGE RAGE :lol: :lol: :lol:

KitemanSA
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Post by KitemanSA »

ladajo wrote:Kite,
That would require Joseph to understand the fundamental points of why Polywell. I think he still doesn't get it.
Seems you are correct. And in truth I don't think he WANTS to. It would spoil his fun.

hanelyp
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Post by hanelyp »

I stated that the toroidal field would vary with 1/R (major radius), not 1/r (minor radius), which Joseph challenged with an improper application of the solenoid magnetic field approximation.

I maintain that the magnetic field from the plasma current will increase with r within the volume of the plasma, then decrease with 1/r outside the plasma. I also maintain that skin effect will have little effect on the distribution of current in the plasma. Uniform current was an approximation I took for back of the envelope figuring.

Joseph Chikva
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Post by Joseph Chikva »

hanelyp wrote:I stated that the toroidal field would vary with 1/R (major radius), not 1/r (minor radius), which Joseph challenged with an improper application of the solenoid magnetic field approximation.

I maintain that the magnetic field from the plasma current will increase with r within the volume of the plasma, then decrease with 1/r outside the plasma. I also maintain that skin effect will have little effect on the distribution of current in the plasma. Uniform current was an approximation I took for back of the envelope figuring.
I stated that Earth is flat< I stated that Earth lays on three whales, though I thought earlier that Earth lays on three elephants.

Joseph Chikva
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Post by Joseph Chikva »

KitemanSA wrote:What happened to the significant toroidal field? You said that was 1/r too. How can it be?
I said that in all area near plasma poloidal proportional to 1/r, while toroidal is comparatively uniform in TOKAMAKs. As poloidal field is created by flowing in plasma axial current and toroidal by bent in donut long solenoid or set of short solenoids. Superposition of two these field provides required for confinement magnetic configuration. All is simple, my little friend.
But the solenoid is bent into a circle which makes the field at the inner end of the minor diameter higher than at the outer end.
This is effect is not significant as more significant in all toroidal plasma machines is so called "balloon effect" caused by non-equality of internal and external side areas. As force=(gas pressure multiplying on side area) is higher from inside of donut than outside and donut has tendency to increase its major radius. But that problem is easily solved by additional control coils and feedback. As additional vertical mag field can create the force on current carrying conductor balancing ballon effect.

KitemanSA
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Post by KitemanSA »

Joseph Chikva wrote:
KitemanSA wrote:What happened to the significant toroidal field? You said that was 1/r too. How can it be?
I said that in all area near plasma poloidal proportional to 1/r, while toroidal is comparatively uniform in TOKAMAKs.
Please don't fib.
Your opening statement was:
As gradient of B by minor radius is positive for Stellarator and negative for TOKAMAKs.
There was no statemenent about "near plasma".

Joseph Chikva
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Post by Joseph Chikva »

KitemanSA wrote:Please don't fib.
Your opening statement was:
As gradient of B by minor radius is positive for Stellarator and negative for TOKAMAKs.
There was no statemenent about "near plasma".
It was meant. As speaking about confinement concept nobody except you and Mr. hanylep speaks about magnetic field inside plasma. But only near plasma. As mag pressure is from outside.

KitemanSA
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Post by KitemanSA »

Back step, shuffle shuffle, slide to the side, back step, pirouette. Gee you dance nice!

Joseph Chikva
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Post by Joseph Chikva »

KitemanSA wrote:Back step, shuffle shuffle, slide to the side, back step, pirouette. Gee you dance nice!
This is my answer to Mr. Hanilap:
Magnetic field inside plasma that is strongly diamagnetic by its properties? You can calculate such fields? Yes, I talk about mag field outside the plasma.
Enjoy.

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