May Report Released.

[Matt M]

Summary

•Plasmoid density triples, fusion energy rises with purer plasma
•But not pure enough—LPP tracks down what disrupted the filaments
•LPP has new paper for Spain conference
•US Department of Commerce finds all in order with LPP-Iran Scientific “Fusion for Peace” Collaboration
•LPP has rendezvous with Chu as Congress sets eye on ITER costs
Plasmoid density triples, fusion energy rises with purer plasma

http://lawrencevilleplasmaphysics.com/index.php?option=com_lyftenbloggie&view=entry&year=2013&month=05&day=14&id=97:lpp-focus-fusion-report-may-14-2013&Itemid=90

[DerekShannon]

Feel free to ask questions about the report in this thread!

[Joeviocoe]

DerekShannon wrote: “Over the longer run, we are looking at ways to
have a single-piece cathode made out of tungsten or tungsten-copper in order to eliminate the
rod-plate joint altogether. These steps should get rid of the filament disruption for good, enabling
results to catch up with theory.”

Will this be a departure from the original plan to go with a Beryllium set of electrodes to become transparent to X-Rays (so as not to absorb the usable energy yield) ???

[Lerner]

Beryllium is way too expensive for these experimental designs and is not needed at our current level of x-ray output–too small to seriously erode the cathodes. At some point we will have to switch over to it, but not yet.

[meemoe_uk]

In the report :
When talking about evaporated metal impurities in the plasma caused by arcing, you say you will plate the cathodes with silver.

Why do this?
Silver has a slightly lower melting and significantly lower boiling temperature than copper, and plating is prone to ex-foliation. I don’t see how silver plating will help with reducing arcing or metal evaporation.

[vansig]

However, silver has high electrical and thermal conductivity. how to balance this?

[meemoe_uk]

Yes, that’s the way I see it. Silver is a better conductor so there will be slightly less arcing, but when the arcs come, silver evaporates more than copper. The problem isn’t solved, it’s shifted.

Best guess at the moment is that silver plating is doing another job – it will smooth over the surfaces of the cathodes, which have developed a few surface features from arc erosion which then act as foci for more arcs.

It’s a stop gap solution until the tungsten arrives.

[Francisl]

I have two questions about the plasma.
1. Can the plasma sheath be made diffuse enough and cover enough electrode area that the discharge intensity is reduced to the point where metal vaporization is insignificant?
For example can a corona charge be created around the electrodes to create a larger conductive area around the electrodes?
2. The metal ions are much heavier than the deuterium ions. Can the momentum of the metal ions be used to separate them from the pinch?

[Tulse]

Although carbon nanotubes may not be available in practical amounts currently, it appears that the metallic versions may have better thermal and electrical conductivity than most of the metals discussed. Would they be a potential replacement for the electrodes, or at least as a sheath? Would their properties at least in theory help to solve some of the evaporation issues?

[Chuctanunda]

Great to hear about the triple plasmoid density achievement. I would like to know what is a realistic level of output above break even. What level of output will make this process economical? What level will make it competitive with conventional electricity production? Forgive me for being a little anxious, but I really want to see this work..

[zapkitty]

Chuctanunda wrote: Great to hear about the triple plasmoid density achievement. I would like to know what is a realistic level of output above break even. What level of output will make this process economical? What level will make it competitive with conventional electricity production? Forgive me for being a little anxious, but I really want to see this work..

The folks at LPP use the term “scientific feasibility” instead of “break even”… a point at which it is demonstrated that the concept will work. As for the amount of joules per pulse they would expect to need to meet that criterion? 30,000 joules. It’s mentioned in the paper in the section about filament disruption:

If we can get yield up to our theoretical expectation of over 1 joule, our scaling calculations tell us that with higher current we can make it all the way to the 30,000 J that we need to demonstrate scientific feasibility.

… and the Sankey diagram on this page shows that they are going for about 66,000 joules for the proposed power generator.

Was this the sort of thing that you wanted to know?

[Chuctanunda]

Thank you, Zapkitty:-) I realize this is uncharted territory they’re venturing into. Scientific feasibility is the goal at this stage. I was also looking for the long term potential. Once scientifically feasible, LPP will be competing with existing technology, as well as new concepts like the thorium reactor. Is it possible be gage the likelihood of success at this later stage of development?

[zapkitty]

Chuctanunda wrote: Thank you, Zapkitty:-) I
realize this is uncharted territory they’re venturing into. Scientific
feasibility is the goal at this stage. I was also looking for the long
term potential. Once scientifically feasible, LPP will be competing
with existing technology, as well as new concepts like the thorium
reactor. Is it possible be gage the likelihood of success at this later
stage of development?

I can say without reservation that, if it works, aneutronic (pB11)
fusion trumps all other power sources under current consideration.

Start off with the simple fact that fusion power generators can never
go critical or melt down. Ever.

And fusion has an extreme advantage over fission insofar as the net
energy from each gram of fuel is concerned… and boron is both cheap
and plentiful.

[em]Aneutronic[/em] fusion then ups the ante with zero radioactive
waste and no debilitating neutron damage to the generator structure.

This will lower total reactor operating costs by a few orders of
magnitude 🙂

And aneutronic fusion enables direct conversion of the fusion energy
output to electricity at high efficiency… no steam, no turbines and
no massive plumbing arrays. This alone would be a game-changer in and
of itself because those turbines are actually the major part of the
cost of a coal or gas-fired plant. So aneutronic fusion will give
extensive savings in this department as well.

And then there’s the Dense Plasma Focus approach to aneutronic fusion:
“Focus Fusion”

Unlike other candidates for aneutronic power such as EMC2’s Polywell or
Tri-Alpha’s CBFR (Colliding Beam Fusion Reactor) the DPF does not
require expensive adjuncts such as superconducting magnets or neutral
particle beam injectors.

Put very simply it’s basically an artfully crafted spark plug and, yet
again, that should lead to [em]substantial[/em] savings in manufacture
and maintenance over competing designs.

Add it all together and you have an energy source that beats out
everything but another aneutronic generator… and even in that arena
the Focus Fusion concept has its own advantages.

[Chuctanunda]

Once again, thank you. Your answer is everything I hoped for. After viewing the Youtube video that originally promoted focussed fusion at the inception of the LPP project, I was naturally excited about the potential. Fast forward to today and the state of development of the LPP project, and I see what I perceive being very near to a major breakthrough. Increasing the plasmoid density a little more seems like the path to success. As a non-scientist I am fascinated by what those of you in the field of physics are able to accomplish with your knowledge base. I have a sense I may soon be a witness to an historical achievement here. I wouldn’t miss it for the world!

[Tulse]

Nice summary, zapkitty — a great accounting of why this work is so incredibly exciting. It really could be an enormous game-changer.

This is also why I find the apparent lack of funding interest in DPF to be so frustrating. It has such huge potential if it works, and the main issues seem to be engineering, not theoretical, meaning a relatively small investment could determine its potential relatively quickly. An Elon Musk, Bill Gates, or Warren Buffett could use the spare change from their sofa cushions to fund a potentially world-changing technology that could have real-world impact in less than a decade. Why aren’t smart angel investors flocking to the doors of LPP?

[Author]

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