Combining New/Old Approaches for Nuclear Fusion

L2 writes "Sandia National Labs are looking at some old military tech for a shortcut to nuclear fusion. Still the odd little detail to be worked out, such as how to keep the fuel from melting everything during the reaction. " Interesting approach. While much of the recent fusion work seems to have centered around tokamak reacters, from what I've seen, this one harkens back to a different school of thought. The bottomline, IMHO, is that the sooner we have fusion - or another cheap, environmentally clean energy source, the less likely we are to destroy the rest of this planet and hence ourselves.

Comments

"Cheap, clean power will save the environment" NOT

[Great_Jehovah]

The bottomline, IMHO, is that the sooner we have fusion - or another cheap, environmentally clean energy source, the less likely we are to destroy the rest of this planet and hence ourselves.

Yeah, right. And computers will lead to a paperless office hence saving the rainforest.

Cheap power will only lead to increased production capacity and will intensify the demand for raw materials.

People will be able to live in places where it is currently uneconimical to live. The use of said power will also generate a lot of waste heat.

The government will build huge roving automatons with fusion reactors in their bellies to control the population.

All life will be consumed by nanobots which will turn the entire surface of the planet into grey goo which resembles an as yet uninvented flavor of McDonald's shake.

Or something.

A demostration from home - why this isn't easy.

[Silicon_Knight]

Here's a quick plasma physics demostration that you can do at home:

Take a wooden splint, like one of those things used to stir coffee.

Stick it into something that will stand it up, say a pencil eraser, or a piece of bread.

Light the tip and stick it into the microwave. Nuke for 1 minute.

Voila. what you will witness is a plasma being formed at the flame. A redox reaction is occuring, with atmospheric oxygen oxidizing the wood. The microwave energy is somehow disrupting the flow of the ionized particles (electrons and all) and forming your plasma.

Now, generating this plasma is one thing (Try it! It doesn't damage the microwave) but controlling this plamsa is a totally different story. Think you can accelerate this plasma down a tube and aim it at some target, a la plasma rifle from Quake? If you can do that, gimme a call 8-)

This demo illustrates the precise nature of fusion research. While generating a fusion reaction isn't difficult, it's controlling the reaction that's being a pain in the arse...

-=- SiKnight

Re:Military Technology != Public Technology

[Upsilon]

Actually, modern weapons are all fission-fusion hybrids. Your basic "H-bomb", more technically a fission-fusion bomb, has a fission trigger (that normally uses plutonium) that results in a fusion reaction from the stored hydrogen. It's a relatively "clean" weapon, in that there is a big explosion but not a whole lot of fallout.

But things don't stop there. There are fission-fusion-fission bombs that start out like a fission-fusion bomb, but the fusion reaction is used to create another fission reaction in a sheath of material on the outside of the bomb. Typically, this sheath is made of common U-238, as opposed to the U-235 that is used in uranium based fission bombs and nuclear reactors. U-238 actually has more destructive potential than U-235, but it wasn't used in earlier bombs because it's simply impossible to start a fission reaction in it under normal circumstances. That's why you need that fusion trigger. Fission-fusion-fission bombs are basically the most destructive weapons in existence, and unlike fission-fusion bombs they result in a lot of fallout as well. They are nasty things.

Here's an interesting fact: a lot of modern warheads can be converted between fission-fusion and fission-fusion-fission quite easily. Since the U-238 is typically a sheath surrounding the bomb it can be replaced with a simple lead sheath quite easily. It's nice to have versitile nuclear weapons, isn't it. If you want to blow something up, use the lead sheath. If you want to REALLY blow something up and have no intention of taking over the land you blew up anytime in the near future, use the U-238 sheath.

Want to hear about some even nastier weapons? Sometimes called "hemisphere bombs", cobalt-salted nuclear weapons have the ability to, well, kill everything on a hemisphere. They don't do this with a really big explosion, but rather with intentional and very lethal fallout. If I remember correctly, they use a sheath of cobalt-59. The cobalt-59 is changed to cobalt-60 when the bomb blows up. Cobalt-60 is special because it is very radioactive with a half-life perfect for totally annihalating your enemy. It's half-life is 5 years, which is short enough to be fatal if you are simply exposed to it, rather than just causing cancer which might shorten your life-span in the long-run, yet long enough to make waiting it out in some underground bunker rather impractical. Your cobalt-salted bomb is detonated in the upper atmosphere to spead the cobalt-60 all over your enemy, at which point they are as good as dead.

In case any of you find my fascination with nuclear weapons a little sick, I'll tell you in advance: I don't care. Nukes are fun!