reddit: We are nuclear fusion researchers, ask us anything

[Joseph Chikva]

That is indeed B^4 R^3 scaling. I have seen this in multiple texts and papers. Even knowledgable critics have accepted this scaling. It is basic to plasma fusion science.

It is not basic to plasma fusion science. But basic confusion of fusion lovers. Once again: in case it would work, it would be quite universal for any fusion approaches and economical fusion would be reached many years ago.

[ladajo]

Show us a reputable citation where a real plasma physicist says it is not true.

So far, you only offer your (lone) opinion.

Cite, and then Argue.

Cite, Argue.

Simple.

[Joseph Chikva]

Show us a reputable citation where a real plasma physicist says it is not true.

So far, you only offer your (lone) opinion.

Cite, and then Argue.

Cite, Argue.

Simple.

It's so easy, ladajo, that I do not know where I should search such a link. And please release me from reading of basics of basics only for proving you something. I need not that. You have a choice: to believe me or not believe me or to follow to my logic that is simple and well understood.

[ladajo]

Bullshit flag thrown.

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

[WizWom]

Joseph,
Try these threads:

viewtopic.php?p=18445&highlight=alphas#18445

viewtopic.php?t=1211&start=0&postdays=0 ... ght=alphas

(second page is hwere Dr. Nebel talks about the alphas)

The quote you need to look at is:

If you want to determine if the alphas hit the coils, the relevant parameter is roughly the comparison of the alpha Larmor radius to the width of the confining magnetic field layer.

That is the math I did earlier; that is, the alphas will be hitting the coils EVEN at extremely high Tesla magnetic fields.

[Joseph Chikva]

Bullshit flag thrown.

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

Are you talking about this?

1. We don’t rely on any scaling results from small devices. The reason for this is that these devices tend to be dominated by surface effects (such as outgassing) and it’s difficult to control the densities in the machines. This is generally true for most plasma devices, not just Polywells.

So, no any proven scaling in 2009.
For 6 or 7 generations of already built machines.
Now everybody can say that recent device was not big enough as

for this is that these devices tend to be dominated by surface effects

. Then bigger and bigger.
In TOKAMAKs with which you like to compare Polywell (funny) at least doubtless improvements where observed from generation to generation.
Regardless to surface or any other effects.

[KitemanSA]

As for any ignition fusion machines alphas are the main heating factors. Why they will not heat plasma in Polywell? Are you aware with other mirror machines?
Also permanent repeating beta=1 B**4*R**3 at constant beta does not seem seriously for me. As in the beginning of the same post Dr. Nebel speaks that neither experiment shown desired scaling.

Again, you have mis-read the statement. He did NOT say that neither experiment showed scaling, he said

We don’t rely on any scaling results from small devices.

He then goes on to say

3. As discussed by several people earlier, power output for a constant beta device should scale like B**4*R**3. All fusion machines scale this way at constant beta. Input power scales like the losses. This is easy to derive for the wiffleball, and I’ll leave that as an “exercise to the reader”.

Since Polywells should be constant beta=1 devices, the B^4R^3 scaling for power should hold.

PS: Emphasis added in quotes.

[KitemanSA]

[/quote]

Bullshit flag thrown.

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

Are you talking about this?

1. We don’t rely on any scaling results from small devices. The reason for this is that these devices tend to be dominated by surface effects (such as outgassing) and it’s difficult to control the densities in the machines. This is generally true for most plasma devices, not just Polywells.

So, no any proven scaling in 2009.
For 6 or 7 generations of already built machines.

Do you have ANY concept of the history of Polywell? Are you aware that WB6 was the first successful Polywell (except the MPGs which were essentially just fusors). There have been TWO generations of current Polywell design (WB6/7, and WB8 ). We shall see.

Now everybody can say that recent device was not big enough as

for this is that these devices tend to be dominated by surface effects

. Then bigger and bigger.
In TOKAMAKs with which you like to compare Polywell (funny) at least doubtless improvements where observed from generation to generation.
Regardless to surface or any other effects.

And you believe that there has been no history of improvement from WB6/7 to WB8? Based on what please? Your opinion? Show me "fact".

[Joseph Chikva]

Again, you have mis-read the statement. He did NOT say that neither experiment showed scaling, he said

Really? May be we mean different things using the same word "scaling"? By my understanding can be proved experimentally when from experiment to experiment you have doubtless improvement and you empirically come to the certain dependence of desired parameters on some input parameters. So, till WB6 this dependence has not been shown. That is the fact. Now, as you are aware better of Polywell's history please note me and others about any improvements for WB8 or 7.
"As Polywell is intended to run at beta=1" is not argument as this is impossible regardless to what said honorable Dr. Nebel. As he also said to patent office examinator that "well known that ions in EOC devices move strictly radially" while examinator considered Polywell as conventional thermal magnetic trap and compared that with Russian "Galatea".
I do not sure that Dr. Nebel is more qualified in plasma physics than paid by US Government and many times examined himself examinator.
As beta=1 is nonsense
And scaling B^4R^3 is nonsense too.

[ladajo]

Too bad you can't prove it.

[Joseph Chikva]

Too bad you can't prove it.

I need not. As 60 years fusion research history proves that universal for any approach "law" B^4*R^3 does not work. In opposite case we would be already powered by fusion reactors.
And my advise is to not believe in myths like "constant and equal to 1 beta, 10 kt explosion for TOKAMAK, beaten to blood many times scaling law B^4", etc.
As all these are too far from true.

[KitemanSA]

[/quote]

Again, you have mis-read the statement. He did NOT say that neither experiment showed scaling, he said

Really? May be we mean different things using the same word "scaling"?

Seems possible. You seem to insist that "gain" scaling is the only scaling that exists while the rest of the world seems to recognize three scalings, "power", "loss", and the difference between them "gain". And while talking about small scale units not being relied upon, Dr. N's examples (e.g., outgassing) relates to LOSSES, not power.

By my understanding can be proved experimentally when from experiment to experiment you have doubtless improvement and you empirically come to the certain dependence of desired parameters on some input parameters. So, till WB6 this dependence has not been shown. That is the fact. Now, as you are aware better of Polywell's history please note me and others about any improvements for WB8 or 7.

Since WB7 was the same scale as WB6, just more robust and with modified loss mechanisms, "power scaling" research would have been somewhat limited. I am pretty sure they did some, but how much is in question. WB8 was both larger and had higher power magnets. But as of the last data I recall, were still exploring the lower beta part of the machine's capability.

"As Polywell is intended to run at beta=1" is not argument as this is impossible regardless to what said honorable Dr. Nebel.

Here ya go, acting as if you are god, making proclamations with no support. They ran WB6 at beta=1, repeatedly. The fact that you say it is impossible just demonstrates that you don't learn. (There ain't no sich animal said the hick when seeing the elephant.)

As he also said to patent office examinator that "well known that ions in EOC devices move strictly radially" while examinator considered Polywell as conventional thermal magnetic trap and compared that with Russian "Galatea".

So because a "patent examiner" thought it was a thermal mag trap, you take this as proof that it is? Wow. tsk tsk.

I do not sure that Dr. Nebel is more qualified in plasma physics than paid by US Government and many times examined himself examinator.
As beta=1 is nonsense
And scaling B^4R^3 is nonsense too.

So you (and seemingly ONLY you) say, but never show. And since Dr. N. worked in such matters and LANL(?), I suspect he IS much more knowledgeable than the patent "examinator". And more than you too!

[tomclarke]

I do not sure that Dr. Nebel is more qualified in plasma physics than paid by US Government and many times examined himself examinator.
As beta=1 is nonsense
And scaling B^4R^3 is nonsense too.

No-one can be sure of anything in this world, as Kite will agree, but Nebel is a well-qualified and published academic plasma physicist, it would be strange if somone with such specialised knowledge ended up a patent examiner.

[KitemanSA]

Too bad you can't prove it.

I need not. As 60 years fusion research history proves that universal for any approach "law" B^4*R^3 does not work. In opposite case we would be already powered by fusion reactors.

This statement proves that you are yet again confusing "power" and "gain" scaling. If tokamaks scale power by B^4*R^3 and scale LOSSES by B^5*R^3, then tokamaks would NEVER produce a gain. (I said IF). What keeps happening is that new and unexpected LOSS mechanisms keep cropping up with larger scale. Given the clean geometry expected of Polywells, Dr. B. seemed to think that such "unexpected mechanisms" were unlikely to happen. He wanted to jump strait to ~1.5m radius (IIRC).

And my advise is to not believe in myths like "constant and equal to 1 beta, 10 kt explosion for TOKAMAK, beaten to blood many times scaling law B^4", etc.

Beta=1 has been demonstrated repeatedly; how "constant" it was is unknown to me .
Didn't someone calculate the design energy content of the ITER? What was that number? Anyone?
Everyone but you seems to know and accept the "beaten to blood many times scaling law B^4". Maybe it is your understanding that is "myth"ing!

[Joseph Chikva]

I do not sure that Dr. Nebel is more qualified in plasma physics than paid by US Government and many times examined himself examinator.
As beta=1 is nonsense
And scaling B^4R^3 is nonsense too.

No-one can be sure of anything in this world, as Kite will agree, but Nebel is a well-qualified and published academic plasma physicist, it would be strange if somone with such specialised knowledge ended up a patent examiner.

The man can solve differential equation Poisson and some others. But who says "beta=1" and scaling B^4 did not go far from Kiteman. Good luck all.
5 Generations unsuccessful then all people weak and declared about success of WB6 for obtaining some little financing enough for buying bread for 2-3-4 people. What scaling are you talk about?