Talk-Polywell.org

John Slough has written an article "A compact fusion reactor based on the staged compression of an FRC". He describes an approach to forming and heating an FRC that "is expected to achieve fusion gain as large as 10" with D-T fusion. He describes a number of constraints on device parameters to ensur...

Suppose that, on each pulse, a fraction s of the He3 does not fuse. So a fraction s^2 survives two pulses, a fraction s^3 survives three pulses, etc., and a given He3 survives n=s/(1-s) pulses on average. Now let c = the energy per pulse per He3 to heat and compress the plasma, y = energy yield when...

With He3 selling for $20,000/g and tritium for $30,000/g, I wonder if they can make a profit running on D-D without generating net electricity. At least until the markets for those gasses crash.

There's a new paper entitled "Polywell revisited" at https://arxiv.org/abs/2508.06761 by Jaeyoung Park, Nicholas A. Krall, Giovanni Lapenta, and Masayuki Ono Here's the abstract: The Polywell fusion concept, originally proposed by Robert W. Bussard in 1985, has been investigated for over four decade...

Hmm. So I guess the strategy is to use D-D to tune the device for the right plasma conditions (e.g. triple product), then D-He3 and further tuning to maximize the fusion, then yet more tuning to maximize the direct energy out. Hopefully that will demonstrate net electricity production. It seems to m...

Do you expect they'll work on DT for now, and work up to using He3 later? Or will they have to be using He3 to get net electricity without using a thermal cycle?

It's not entirely clear what exists and what's simulated. I assume everything through the first paragraph in section 3 exists, and everything after the phrase "simulation results" within section 3 is simulated. I'm not sure about the parts in between. In particular, have they tried puffing in hydrog...

On further examination, maybe this doesn't look so good. First, I should correct my nomenclature. I referred to this as "beam-target fusion", but it's actually closer to a colliding beam reactor. There was a comparable proposal by Rostoker, Binderbauer and Monkhorst [1]. Lampe and Manheimer [2] poin...

On further examination, maybe this doesn't look so good. First, I should correct my nomenclature. I referred to this as "beam-target fusion", but it's actually closer to a colliding beam reactor. There was a comparable proposal by Rostoker, Binderbauer and Monkhorst [1]. Lampe and Manheimer [2] poin...

So, bang two spinning (counter-rotating? not clear from the paper) rings of plasma together at (presumably) high frequency to get fusion? Is that the gist of it? I believe it's a single FRC. Magnetic fields constrain it axially, so all the particles in the plasma are in a potential energy well. The...

Yes, the article about the soldered joints was very interesting. Apparently they plan to use compressed air to blow solder wherever they want it. I wondered how they'd avoid the solder short-circuiting the various joints - but then realized that would be no worse than the stainless steel that alread...

I decided quite some time ago that Commonwealth Fusion Systems would be successful with ARC. That was mainly because the they would use high temperature superconductors that would give them a stronger magnetic field (suppressing instabilities and allowing the device to be much smaller, saving cost a...

I recently ran across a paper by Parisi, Diallo, and Schwartz (DOI 10.1088/1741-4326/ad7da3) discussing the use of spin-polarized fuels to improve the performance of tokamaks. The cross section for D + T → α + n, would be increased by 1.5 if the fuels were injected with parallel polarization. I star...

Given my bad mental health, please forgive me. But this reads awful: they are quietly saying their system doesn’t work. Can anyone help understand and/or cheer me up? RERT Well, Polaris is certainly not generating electricity YET. But we shouldn't expect that. As I read the paper, they expect their...

Article with David Kirtley among the authors published monday this week: https://arxiv.org/abs/2501.03425 An improved understanding of Field Reversed Configuration (FRC) merging and stability in high acceleration and compression magnetic fields is needed to speed up the development of the pulsed fu...