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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:Stronger = more cost. Why stronger if strong enough?
Yes, more cost on several hundreds dollars. Even schoolboys build similar in father's garage.
"Strong enough" for allowing you to speak about scaling "B^4"
When you'll make really stronger you will see that this scaling does not work for any device.
They made WB8 stronger. They should tell B^4 from that, at least until a full scale unit is built. They also made it ~2X bigger. They should be able to tell r^3 scaling from that, at least until a full scale unit is built.

You want more? Build it. As you say, a couple hundred dollars. So build one.
A couple hundreds dollars for stronger magnets of this size.
Build it? I have not any interest to build it, do not see the sense for building to be sure that I know without building: scaling (fusion rate)~B^4 does not work for any device. As this scaling law would be legit only in case of the same plasma behavior at different densities.
Stronger MaGrids inevitably will confine some of charged reaction products. And they will thermalize plasma.
I doubt that this is the main reason why developers did not use stronger field in WB6. As technically to make of much stronger magnets of these sizes is very easy.
So, let's wait WB8 results.
Good luck.

mvanwink5
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Post by mvanwink5 »

Joseph,
I think the decision was made in a committee based on budgets and keeping a low political R&D profile. On the other hand, and KitemanSA may be able to confirm this, a useful device can be built without the very high magnetic fields using D-D as the fuel instead of Boron and Hydrogen. Thanks for your best wishes, we are all hoping for good results.
Best regards
Near term, cheap, dark horse fusion hits the air waves, GF - TED, LM - Announcement. The race is on.

KitemanSA
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Post by KitemanSA »

I suspect that if pB&J turns out to be problematic then the first full scale unit would run D-T, not D-D. The only real reason to run D-D now is that it takes special handling permits and all sorts of admin overhead to use Tritium. Deuterium is "over the counter". Anyone can buy it.

TallDave
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Post by TallDave »

B^4 power scaling is straightforward -- power is density squared, density is B field squared. All fusion machines scale this way at constant beta. Plasma behavior will probably be similar enough at the densities of interest (consider Rick's ITER comparison, with no ion focusing), but of course you can't really ever know till you build it.

The real concerns are with the loss scaling, and if Polywells fail it will very likely be here. Does it look like B^.25 * R^2, as Bussard suggested? Or is it something more like B^2*R^2? WB-8 gives us some more data points along the range. We don't know precisely what the reported "excellent" confinement means, but it certainly seems to bode well.

So at this point, at least for people that have looked at the research, Polywell can reasonably be considered a pretty good shot at producing an economically viable net power reactor. In future tests we may find some insuperable problems, but that's where we are now.
n*kBolt*Te = B**2/(2*mu0) and B^.25 loss scaling? Or not so much? Hopefully we'll know soon...

TallDave
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Post by TallDave »

ladajo wrote:In our case we thought initially that the WB6 machine produced 1.46mW, whereas looking at it this way, it produced 5mW.
2.5E9 fus/sec
1.25 T+p events/sec for a total of 5.04E15 in energy
1.25 He3 + n events/sec for a total of 4.09E15 in energy
and secondary
1.25E9 He4 + n events/sec for a total of 2.2E16 in energy
which gives
3.11E16 in total energy, converted to Watts gives
.005 Wattsecs
or
5mW

Thoughts?
Interesting notion, I don't remember ever looking at a T side reaction for WB-6. Would you need to also go back and re-figure the fusion rate based on the neutron count, or is it still the same? Or maybe you did that already and I didn't notice.

Sadly, the number of counts within the sampling period is so small the error is probably bigger than the effect. But still an interesting idea.
n*kBolt*Te = B**2/(2*mu0) and B^.25 loss scaling? Or not so much? Hopefully we'll know soon...

Joseph Chikva
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Post by Joseph Chikva »

KitemanSA wrote:I suspect that if pB&J turns out to be problematic then the first full scale unit would run D-T, not D-D. The only real reason to run D-D now is that it takes special handling permits and all sorts of admin overhead to use Tritium. Deuterium is "over the counter". Anyone can buy it.
I think that Navy if needed can buy tritium too. And if I recall correctly one Canadian company sells Tritium.
It does not seem seriously for me to speak about much difficult for realization pB reaction when during for about 60 years even much easier DT is not realized.
TallDave said: "And where we are". I am declaring once again that we are here: neither of fusion approaches allows to build commercial reactor in near couple of decades. Including beloved Polywell. As Polywell's problems are visible even with open years.

KitemanSA
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Post by KitemanSA »

We shall see.

Tick tock, tick tock.

KitemanSA
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Post by KitemanSA »

TallDave wrote:
ladajo wrote: Thoughts?
Interesting notion, I don't remember ever looking at a T side reaction for WB-6. Would you need to also go back and re-figure the fusion rate based on the neutron count, or is it still the same? Or maybe you did that already and I didn't notice.

Sadly, the number of counts within the sampling period is so small the error is probably bigger than the effect. But still an interesting idea.
I suspect that the very weak field of WB6 would not have held the T in. The alphas has a 5cm GR with the 7(?)T field with the energy @~4MeV. The T at ~the same energy, 1.5x the mass for each charge and 1/70x the field would have a GR of what, ~5*1.5*70=5m. I think this would escape a .3m MaGrid.

Joseph Chikva
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Post by Joseph Chikva »

KitemanSA wrote:We shall see.

Tick tock, tick tock.
I see today conceptual problems. Yes, you will see tomorrow the results. Or more truly will not see anything neither tomorrow, nor the day after tomorrow, nor in 50 years.

TallDave
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Post by TallDave »

It will certainly be interesting if they pick up the p-B11 contract option that has been specified. That would be the first time anyone has tried that in a reactor-type machine, iirc. And the results could shed a lot of light on how brem might be handled.
n*kBolt*Te = B**2/(2*mu0) and B^.25 loss scaling? Or not so much? Hopefully we'll know soon...

Northstar
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Post by Northstar »

If they pick up the p-B11 option it would almost certainly mean that they are convinced that the WB-8 is performing as planned / theorized. It would also mean that they have D-D fully in hand as feasible to proceed with further at larger scale or they would not be trying the much harder p-B11 reaction. It would be almost as good as a publishing a report giving details on their results to date.

If they don't pick up the p-B11 option, it doesn't mean that D-D (or in fact D-T) is NOT feasible, just that they don't consider that the WB-8 would not be able to give meaningful information on p-B11.

It would not be positive for the overall feasibility of the polywell concept if the don't pick up the option, however, IMHO.
There are strange things done in the midnight sun....

KitemanSA
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Post by KitemanSA »

Joseph Chikva wrote:
KitemanSA wrote:We shall see.

Tick tock, tick tock.
I see today conceptual problems. Yes, you will see tomorrow the results. Or more truly will not see anything neither tomorrow, nor the day after tomorrow, nor in 50 years.
If you are correct, we will see nothing in 50 years.
If Dr. Bussard is correct, we will see a lot in 50 years.

Unless people like you prevent people who "don't know" from doing the research to find out, in which case you are your own self-fulfilling prophecy.

Joseph Chikva
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Post by Joseph Chikva »

KitemanSA wrote:Unless people like you prevent people who "don't know" from doing the research to find out, in which case you are your own self-fulfilling prophecy.
Hehe
Because I said that confined ions will thermalize plasma? But that's true
Or because despite you and others I said that two-stream instability should be investigated for Polywell? Dr. Nebel investigated and came to conclusion that only high themal electrons could prevent this type of instability.
Or because I said that by increasing of plasma density electron-ion two straem instability also may be an issue for Polywell? That's true too.
Etc. etc. etc.

I see that you aren't able to argue. Because to ask questions doesn't mean to be the enemy. I am not enemy. On the contrary I help you to get rid of illusions.

Roger
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Post by Roger »

TallDave wrote:It will certainly be interesting if they pick up the p-B11 contract option.
Yes, interesting and exciting. & if EMC2 shows P-b11 fusion, even the Tok guys will take notice, P-b11 fusion with Dr. B's predicted low Bremm would make some waves, and I would would be cheering loudly.

IF P-b11 can be done by Polywell, that makes Lunar He fueled Polywell's very interesting...
I like the p-B11 resonance peak at 50 KV acceleration. In2 years we'll know.

KitemanSA
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Post by KitemanSA »

Joseph Chikva wrote:
KitemanSA wrote:Unless people like you prevent people who "don't know" from doing the research to find out, in which case you are your own self-fulfilling prophecy.
Hehe
Because I said that confined ions will thermalize plasma? But that's true
But are they confined long enough to be a problem? The statement was not that they were "confined", just that they would be unlikely to hit the MaGrid on their way out. How many transits to thermalize? How many transits to escape? Do you know? If not, you're just guessing too.
Joseph Chikva wrote: Or because despite you and others I said that two-stream instability should be investigated for Polywell? Dr. Nebel investigated and came to conclusion that only high themal electrons could prevent this type of instability.
Reference? Quote (in context)?
Joseph Chikva wrote: Or because I said that by increasing of plasma density electron-ion two straem instability also may be an issue for Polywell? That's true too.
It is also true that Aliens "may" invade tomorrow. Which is more likely?
Joseph Chikva wrote: Etc. etc. etc.
E.g.? E.g.? E.g.?
Joseph Chikva wrote: I see that you aren't able to argue.
Really? What have we been doing?
Joseph Chikva wrote:Because to ask questions doesn't mean to be the enemy. I am not enemy. On the contrary I help you to get rid of illusions.
First remove your own rose colored glasses?

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