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Discuss the technical details of an "open source" community-driven design of a polywell reactor.

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kunkmiester
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Post by kunkmiester »

Nanotubes are going to get in the way. The point is to get the hydrogen to fuse with the boron--that's not going to happen if the boron is in a protective shell.
Evil is evil, no matter how small

chrismb
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Post by chrismb »

No, no idea what you mean.

I fear that whatever concept you have conjoured up into your head, it is likely to remain there. You are not, in the slightest, clear. What mechanism are you trying to cause, how and why? It is not at all clear.

I don't really know why I am asking you because I have a bad feeling this is going to go so far in the opposite direction of anything comprehensible, but, hey, I'm an easy push-over when it comes to getting me hooked into exploring someone else's ideas.

Where's the beef? How do fusible nucleii get close to each other, and how do they dodge the electrons on the way?

chrismb
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Post by chrismb »

Santoslhelpa wrote:im not here to get insulted.
where's the insult? I'm saying that you are not clear. Be clearer. How do fusible nucleii get close to each other, and how do they dodge the electrons on the way?

As far as people go who are prepared to debate a poorly explained idea, there aren't many as prepared to debate such as I am. If you don't want feedback, then you've gone the right way about it. If you really do want feedback, then answer the questions: How do fusible nucleii get close to each other, and how do they dodge the electrons on the way?

chrismb
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Post by chrismb »

1) You can have fusion in a plasma where there are ions and electrons that float around independently. In this case, if the electrons bump into each other, no big deal. If the ions bump into each other then [very] occasionally you may get a fusion. If the electrons bump into the ions, then you get bremsstrahlung radiation.

In a usual plasma, it is 'neutral' or very near neutral, so there are as many ions as electrons. So there are plenty of electrons for the ions to dodge.

2) You can also have fusion between ions that gets thrown fast at a solid or a gas or a plasma. Again, the ion has to go through stuff that has as many electrons as there are protons in all the nucleii. The ion loses large amounts of energy as it pushes through all those electrons.

3) You can also have fusion between the nucleus of an atom that gets thrown fast at a solid or a gas or a plasma. Same outcome as (2) but now there are even more electrons to deal with and lose energy to.

In case (1), like a tokamak, the idea is the energy is kept inside the plasma, mostly. This can't be too hot else the bremsstrahlung radiation is too high, so is limited to deuterium and tritium.

In case (2)/(3), like fusors or Polywells, it doesn't work because all the energy gets lost to the electrons and ions. At least, no-one has yet shown they can defeat the collision losses.

Does your invention defeat the collision losses, or is it a really hot plasma like tokamak?

D Tibbets
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Post by D Tibbets »

A fusion fuel ion or atom that is trapped in a structure like graphene or bucky tubes will not survive long in a plasma. Remember that a plasma is an electrically charged gas- collection of nuclei and electrons that have disassociated from each other and are in a charged particle soup.

Carbon melts at a little over 4000 degrees C, and vaporizes at ~ 6ooo degrees C (?). That is only ~ 0.5 eV. Energies needed for fusion are at least 1000 times as much.

Using some structure to contain a fusion fuel might make sense as a way of packaging a fuel, but only for delivery to the plasma. There would be penalties. The carbon once vaporized and then charged would pollute the system- decreasing the fusion rate and making bremsstrulung even worse.
Now if you are talking about some type of beam target fusion the story is different. If the fuel nucleus is asymmetrical (like deuterium) holding it in some orientation may benefit the fusion crossection. Packing deuterium into nickel such that some type of nuclear reactions might occur (cold fusion) and then bombarding this target with high energy deuterons might be interesting. Has it been done?

In any case, I think any type of beam target fusion is not thought to be able to breakeven. You have to have many opportunities for an energetic ion or atom to hit before a fusion might occur. If you need to re energize the ion between each non fusion collision, you will never make it. An exception to this is muon catalyzed fusion. Unfortunately (or perhaps very fortunately) the wimpy electrons, even if manipulated into certain configurations cannot come close to the coulomb shielding effect of the muons.

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

BenTC
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Post by BenTC »

Here is the analogy... You want two basket balls (fuel atoms) to crash into each other really fast. You place each basketball in the centre of a car and smash the cars together really fast. The car bodies crumple a lot but the basketballs are cushioned and never even get close. So containing the fuel inside nanotubes just wont work. Better to just shoot the basketballs at each other directly.
In theory there is no difference between theory and practice, but in practice there is.

MSimon
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Post by MSimon »

Santoslhelpa wrote:im not here to get insulted.
You will need a thicker skin than that around here.

FWIW I get insulted all the time. And more often than not respond in kind. Not to mention starting in without provocation.
Engineering is the art of making what you want from what you can get at a profit.

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