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Piston-Powered Nuclear Fusion
katarn writes "General Fusion is a startup proposing they can create commercially viable fusion using acoustic shock waves, triggered by 220 precisely controlled pneumatic pistons. Their approach is based on a US Naval research concept called 'Linus' and old research done by General Atomics. They feel we now have the high-speed, digital processing capable of pulling off this feat, where decades ago the technology was not available. I think we can hold off on the 'vaporware' claims for a bit; everyone is aware of the horrible track record for turning fusion concepts into reality, but they don't claim to be the first with the idea or that there are not substantial challenges in the way. If nothing else, it is a fascinating concept."
Los Alamos National Laboratory has further details on this type of fusion, and longtime LANL researcher Ronald Kirkpatrick did an external assessment (PDF) of General Fusion's plans. Popular Science had a lengthy story about the company a while back. The reason they're back in the headlines now is that they've secured enough funding to begin work on a prototype reactor.
I mean, come on, this is just begging for some steam punk artwork!
Skimmed the article, they're planing to do with pistons what would be done explosives in a normal nuclear bomb.
Wouldn't it be funny if it worked?
Colonel Fission is pissed and has vowed to crush General Fusion's puny attempts at creating nuclear energy!
Mod me down, my New Earth Global Warmingist friends!
There's been some modest interest in actively stabilized fusion for a while, but this is the first mechanical scheme.
The basic problem with fusion reactors is that the plasmas aren't stable. Most work to date involves trying to come up with some geometry that produces an inherently stable plasma. So far, nothing works, although some geometries almost work. But it's not that hard to build a small machine that has an unstable plasma. The original Stellerator, in 1951, did that.
The instabilities occur on the order of milliseconds, not microseconds or nanoseconds. That's slow enough that some kind of active stabilization scheme to nudge the instabilities back in line might work. Something with a large number of sensors and actuators. But I'd been expecting electrostatic deflection plates or magnets, not physical pistons.
The research team's other concept, which created fusion by enticing atoms with footballs only to pull them all away at the last second, was named 'Lucy'.
I am become
You could attach four smart mechanical arms to someone's brain stem (with an inhibitor chip of course). Those extra arms could make the millisecond adjustments to keep the instabilities in check. I have to admit this sounds familiar ...
Perhaps if the D-T reactor does really well they can redesign it to handle a fuel composed of hydrogen ions (protons, in other words) and Boron-11 ions. The products of this reaction are helium-4 ions, which are not radioactive and do not induce radioactivity in their containment vessel if they are captured electrically. Electrical capture also avoids the losses associated with converting heat to electricity.
I really hope General Fusion gets this to work, but if I had any money, my money would be on EMC2 Corp, which is working on inertial electrostatic fusion. This or this should get you started on a search for more information.
I wonder if this is related to the suspected fusion that occurs during ultrasound induced cavitation.
-- "It's not stalking if you're married!" My Wife.
Startups, by their very nature, do not succeed on a bet that the technology will be invented. Venture capitalists do not support fairytale wishes.
Startups use existing, proven technology and package it in new ways to serve a need of the consumer. Startups are about commercializing a technology, not inventing it.
What startup does breakthrough research? None.
Research is the luxury of universities (with infinite time horizons) and monopolists like Microsoft .
They're not going to stabilize the plasma at all, if I understand this right (IANANP). It's a pulse fusion model: put your hydrogen in the middle, surround with a working fluid that they refer to as "liquid metal" (made of lead + lithium), fire off pistons to make a pressure wave in the liquid metal and make a burst of fusion in the middle, generating heat. This makes the molten lead even hotter, and it's circulated through a heat exchanger. The cool part, I thought, was that the lead also absorbs radiation so the casing and equipment doesn't fall apart after a few months because the neutron flux made it brittle. That's a neat trick.
The World Wide Web is dying. Soon, we shall have only the Internet.
Perhaps this is a better link for Polywell Fusion.
"General Atomics" Sounds like a company from a 1950's Robert Heinlein novel.
The vast majority of fusion research funds from US government flow through the Department of Energy. The senior guys at the DoE have a few pet approaches to fusion, and 99.9% of the funding goes into those. Innovative, small scale, low cost approaches like this, or IEC polywell fusion are left begging to the Navy for funds, but the Navy has far less money to spend on nuclear research than the DoE.
Only in the vaguest sense. The secondary stage in a thermonuclear bomb is triggered by a fission primary, however the secondary stage in a thermonuclear bomb is not a purely fusion weapon. It's a multilayer sandwich. The secondary starts off with another fission reaction (the plutonium spark-plug), which helps trigger the fusion reaction (lithium deuteride), which in turn boosts the ongoing fission reaction in the spark plug, which in turn boosts the ongoing fusion reaction. Finally it produces a neutron flux which detonates and consumes the secondary casing (depleted uranium, U-238). Most of the energy in a thermonuclear bomb comes from the fission of the depleted uranium protective casing. Thermonuclear bombs do fission 'better' than purely fission bombs. For the record, this was discovered accidentally when Castle Bravo was a much bigger bang than the designers expected.
Relocating to the Vancouver area is a bad point? What world are you living in? On Earth Vancouver is frequently ranked among the planets most livable cities.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
Maybe we should just move all companies and their fusion experiments to one, single 'fusion science park', with each building next to each other in a ring. We then use large bulldozers to smash all the buildings towards the centre at the same time and see what happens?
It's an idea? No?
AT&ROFLMAO
The huge yield of Castle Bravo was more due to the unexpected reactions with lithium-7. It wasn't expected to react, but it does capture neutrons, then decays into tritium + a neutron. The tritium quickly fuses with deuterium and releases yet more neutrons. Much of the yield was from the uranium casing, but the reason was the extra high energy neutron flux from the lithium-7. And the secondary in a TU design has the fusion squeezed from both the spark plug detonation (plus a lot of neutrons) and the ablative pressure, on the tamper, from the primary. I'm going to guess that they used a larger amount of the lithium-deuteride because it was only partially enriched. Which meant a lots of unexpected extra energy and neutrons from the lithium-7.
Mr. Burns: [over the hotline] Oh, meltdown. It's one of these annoying buzzwords. We prefer to call it an unrequested fission surplus.