[Ivy Matt]

I knew there was a non-paywalled version of the Physics of Plasmas paper somewhere. Here it is:

http://www.researchgate.net/publication/236221996_Fusion_reactions_from_150_keV_ions_in_a_dense_plasma_focus_plasmoid

[Ivy Matt]

I don’t know of anyone who attended the UC Irvine talk. Someone from Talk-Polywell is going to the the UW-Madison talk, but I don’t know whether video recording will be allowed.

[Ivy Matt]

It looks like EMC2 is opening up more now that the Navy contract is concluded. Dr. Park will be speaking at the University of Wisconsin-Madison on Monday, June 16, at 2:30 PM.

[Ivy Matt]

It’s been a long time coming, but this is very good news. I would compare it to LPP demonstrating plasmoid formation in the DPF and that most of the fusion occurs within the plasmoid. There are some other unsettled questions about the Polywell, but it’s possible many of them have already been answered and will be the subject of further papers. I’m interested to see if EMC2 exercised the option to experiment with hydrogen-boron fuel. I suspect they haven’t got around to it yet, but who knows? Note that the present set of experiments was not intended to produce net gain from fusion. EMC2 estimates that a 100 MW Polywell fusion reactor will require $200 million to design, build, and test. Whether they will obtain that funding through the US Navy or use their published paper(s) to seek investor funding (or both) remains to be seen.

Jaeyoung Park is giving a seminar at the UC Irvine Department of Physics & Astronomy at 10:45 AM on June 12th.

[Ivy Matt]

Looks about right. And one atomic mass unit is equivalent to about 931.5 MeV of energy.

[Ivy Matt]

Proton-boron fusion begins to occur at an appreciable rate at about 100-150 keV ion energy. Optimum energies for proton-boron fusion are about 100-600 keV. Each reaction produces a total of 8.7 MeV of kinetic energy distributed among the three alpha particles. The extra energy comes from the conversion of mass to energy, as in Einstein’s famous equation.

[Ivy Matt]

The DPF is unusual among nuclear fusion devices in that it is not expected to work better as a fusion reactor at larger scales. The Focus Fusion-1 device is already at the optimum* size for net fusion gain according to Eric’s theory, except that the electrodes will need to be shorter for the final experiments. (*Actually, i believe the DPF could be smaller, but then you’d have the electrodes too close to the plasmoid for comfort.) My understanding is that the major difference between FF-1 and other DPFs is that FF-1 has a greater amperage-to-size ratio than other DPFs.

With regard to the energy output, that’s determined by the frequency of the pulses. Too few pulses and the boron precipitates onto the electrodes. Too many pulses and cooling becomes difficult. I believe 5MW is the minimum viable output, and the maximum viable output is something like 20MW. Of course, if you want greater output, you can always use several devices in one power station.

You can use anything you want as the fill gas. LPP has been using deuterium to achieve the neutron yields they’ve reported. However, as I understand it, using heavier elements is an important factor in achieving higher density. For this reason they don’t expect to achieve net fusion gain until after they switch to using boron with hydrogen.

[Ivy Matt]

I don’t have any personal recommendations, but a search turned up the following:

[em]The Plasma Universe[/em], Curt Suplee (Cambridge University Press, 2009)

It is specifically intended for the layman, but I haven’t read it myself, and couldn’t say how it compares to the books you mentioned.

I also found the following very recent book, which is intended for undergraduates and graduates:

[em]Plasmas: The First State of Matter[/em], Vinod Krishan (Cambridge University Press, 2014)

It looks like it might be interesting, but perhaps a bit advanced for the layman.

[Ivy Matt]

The tungsten anode has already arrived. I believe it was what you saw in the crowdfunding video. Unfortunately, delivery of the tungsten cathode has been delayed to late June:

http://lawrencevilleplasmaphysics.com/tungsten-anode-has-arrived/

[Ivy Matt]

Thanks for bringing this up. I emailed the webmaster, and it should be working now.

[Ivy Matt]

LLNL has made an official announcement:

LIVERMORE, Calif. – Ignition — the process of releasing fusion energy equal to or greater than the amount of energy used to confine the fuel — has long been considered the “holy grail” of inertial confinement fusion science. A key step along the path to ignition is to have “fuel gains” greater than unity, where the energy generated through fusion reactions exceeds the amount of energy deposited into the fusion fuel.

Though ignition remains the ultimate goal, the milestone of achieving fuel gains greater than 1 has been reached for the first time ever on any facility. In a paper published in the Feb. 12 online issue of the journal Nature, scientists at Lawrence Livermore National Laboratory (LLNL) detail a series of experiments on the National Ignition Facility (NIF), which show an order of magnitude improvement in yield performance over past experiments.

The paper (or the abstract, for those who haven’t paid for access to the full article), “Fuel gain exceeding unity in an inertially confined fusion implosion”, can be found here.

[Ivy Matt]

Breakable wrote: Hi Graham,
We really need someone to administer
https://www.facebook.com/pages/Sci-Fi-for-Fusion
Would you like some extra responsibility?

What happened to the page? Another victim of the purge?

[Ivy Matt]

To my knowledge you’re the first author to publish a story in which the dense plasma focus device is used as an actual power source, but I could be way wrong about that. I started writing a story about a year ago that features dense plasma focus technology, but it remains unfinished so far.

I’d think readers of science fiction would readily accept fusion generators some forty years into the future. Compared to other sorts of futuristic technologies, I don’t think that’s much of a stretch. Then again, one could have said the same thing forty years ago.

[Ivy Matt]

DeltaV on Talk Polywell brought up the following development as a possible solution to the brittleness problem:

A novel, more resilient compound material has now been developed by Max Planck Institute for Plasma Physics (IPP) at Garching. It consists of homogeneous tungsten with coated tungsten wires embedded. A feasibility study has just shown the basic suitability of the new compound.

Read more at: http://phys.org/news/2013-05-brittle-material-toughened-tungsten-fibre-reinforced-tungsten.html#jCp

Potential drawbacks I see are availability and cost, and DeltaV suggested that the outside surface should probably be free of fibers to prevent arcing.

[Ivy Matt]

Posted on Talk Polywell yesterday:

http://talk-polywell.org/bb/viewtopic.php?f=10&t=4606

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