6th September update: Yield 1/10 of expected @ 1MA, but might be fixed.

[MTd2]

3. Wouldn’t the contents of the plasmoid be pushed out like a tooth paste?

[vansig]

MTd2 wrote: 3. Wouldn’t the contents of the plasmoid be pushed out like a tooth paste?

eventually, they are. that’s the exit beam. and it should consist of the higher-velocity fusion products that have lower angular momentum

[MTd2]

I mean before the fusion happen, while the plasmoid is shrinking.

[vansig]

MTd2 wrote: I mean before the fusion happen, while the plasmoid is shrinking.

yes. unless the angular momentum is strong enough

[MTd2]

vansig wrote:

I mean before the fusion happen, while the plasmoid is shrinking.

yes. unless the angular momentum is strong enough

What angular momentum? The plasmoid is rotating in the direction of the axis field, the ejection would happen in the center of rotation, so no angular momentum there.

[vansig]

the ions are flowing along the surface of a toroid. the greater angular momentum, the more stretched is the spring. the toroid’s radii both shrink together. the smaller it gets, the stronger the fields, and the higher temperatures can get. particles don’t reach the centre of rotation until the transverse part of their momentum drops to zero

[MTd2]

vansig wrote: the ions are flowing along the surface of a toroid.

Not only on the surface, but when the fuel inside the plasmoid is very hot it ionizes itself to a great degree, so it is not just the surface. This is why I am thinking about the analogy with a toothpaste. When the bulk ions are compressed they are forced out of inner part of the torus. So, when the plasmoid starts to shrink, we have an overpopulations of ion and free hot electrons. They will follow the magnetic lines, but given that:
1.the outer part is already populated by the electrons of the filaments
2.the plasmoid is shriking
3.The field falls by 1/z^3 at the azial axis ( the toroid is a dipole)

The ions and those free electron ends up leaking from the plasmoid.

[MTd2]

The above was meant to be a question without a quesion mark… :s

[Brian H]

MTd2 wrote: Thank you for the compliment about my wedding! 🙂

Now, some questions:

…

2. Protons and electrons will go in opposite directions and collide in higher and higher energies, so there should be extreme thermal losses (x-rays). How that is avoided?

Doesn’t happen. Read the Technical Papers; this is one of the innovations/breakthrough ideas of FF. Use of the High Magnetic Field Effect (HMFE) to advantage keeps the electrons in an energy level which prevents their interfering with the ions. This ability to slash ‘X-ray cooling’ (brehmsstrahlung) is key to the process.

[MTd2]

Brian H wrote: Doesn’t happen. Read the Technical Papers; this is one of the innovations/breakthrough ideas of FF. Use of the High Magnetic Field Effect (HMFE) to advantage keeps the electrons in an energy level which prevents their interfering with the ions. This ability to slash ‘X-ray cooling’ (brehmsstrahlung) is key to the process.

This HMFE depends on the atomic number:

eqs (2) and (3)

http://arxiv.org/ftp/arxiv/papers/0710/0710.3149.pdf

For the proton, or hydrogen, it is much higher, 14GG, for suppressing thermal losses. So, in the case of this experiment, with hydrogen, why wouldn’t the Bremsstrahlung be significant in making the plasmoid small?

[vansig]

Bremsstrahlung losses are significant. but just not significant enough to dominate.

in the high fields, the ions cant transfer their energy to the electrons, which remain relatively cool. this difference is quite striking, and results in much lower Bremsstrahlung losses.
(i don’t have precise measures, but guessing ~50 keV? electron T, compared to 600 keV ion T).

[MTd2]

So, Bremsstrahlung are not significant for Hydrogen at 50KeV, right?

[vansig]

MTd2 wrote: So, Bremsstrahlung are not significant for Hydrogen at 50KeV, right?

I wrote that they ARE significant. (which is why it is a good idea to recover x-rays).

But that they do not dominate. Oh, and 600 keV is the target.

I suppose that, given the expected configuration of the plasmoid, it will be possible to calculate the losses.

[Author]

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