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Skunk Works Reveals Compact Fusion Reactor Details

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Re: Skunk Works Reveals Compact Fusion Reactor Details

#251

Post by [deleted] »

dkirtley wrote: post #176
chton wrote: post #18

Earlier quoted context omitted.

It sounds very similar to the way Helion Energy does it ( http://en.wikipedia.org/wiki/Helion_Energy ). Do you know what the major differences are?

Helion here. There are pretty big differences. They did get the high Beta and compact/modular parts right. The primary differences are that Helion operates entirely pulsed with simple non-superconducting magnets. That allows us to go to higher temperatures, cleaner fuels, directly recovery energy, and if everything works as planned should eliminate the wall concerns and need for particle beams. I do think what they a…

[deleted]

Re: Skunk Works Reveals Compact Fusion Reactor Details

#252

Post by graycat »

adventured wrote: post #187
tonyplee wrote: post #185

Earlier quoted context omitted.

How much dangerous are the neutrons from such device? Similar to radiation, worst? Time sell any oil company stocks, mutual fund holding?

Time to buy airline stocks. If you can put a miniature fusion power plant on an 747 equivalent, airline profit margins will skyrocket. Actually even if you believed there's a chance this Lockheed concept can work, the time to buy airline stocks would be on the back end of this dead bull market that's about to fall off a cliff. And then there's the 20 year wait before it's finally deployed to a commercial airplane.

A fusion powered 747 might be the result, but maybe not! Instead, let's see: With the CFR, we've got dirt cheap electric power. Okay, then we can also use that power to make dirt cheap, very clean water. Then, yup, we can take that water, more of that power, and coal and make jet fuel. And maybe that is what the 747s would continue to use! Maybe!

Re: Skunk Works Reveals Compact Fusion Reactor Details

#253

Post by FiatLuxDave »

wcoenen wrote: post #57

> 100-megawatt reactor measuring seven feet by 10 feet, which could fit on the back of a large truck A typical thermal power station has an efficiency below 50% for electricity generation, so the plant dissipates at least as much heat as it generates electrical power. I wonder how you could get rid of 100MW of waste heat from a volume small enough to fit on a truck. That's a heat flux of more than a megawatt per squa…

I strongly suspect that they are aiming for the same form factor as the GE LM2500 http://en.wikipedia.org/wiki/General_Electric_LM2500. The US Navy likes this form factor, for good reasons.

Note that it converts ~100kW thermal into ~37-47 kW electric. It also has high air flow. I suspect that means that they are aiming to make their fusion reactor small enough that it can replace the burner section of the turbine.

Thermal transfer is still going to be a challenge, unless (Idea!) they are planning on spraying water into the airflow and using heat from neutron moderation in the water to provide primary heat transfer. Hmm, I wonder how much water you would need for 14 MeV neutrons? Let's see, half-value layer is around 10 cm, so if you threw a 40 cm thickness of water across a neutron flux, you'd absorb most of the heat (you could probably catch the rest in the duct casing). That's a lot of water in a pretty small space, but physically possible.

Note that the above is a seat-of-pants calculation and should not be taken as accurate by any means.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#254

Post by revelation »

jfoutz wrote: post #222
rayiner wrote: post #213

Earlier quoted context omitted.

That's hardly ever true. In my experience, Hacker News is full of people from the software field; folks whose professions are often unconstrained by physics,[1] and who have a generally optimistic "this can happen" mentality. That's why everyone here believes we'll have fully self-driving cars in 5-6 years. In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (p…

> Did you know that coal plants, which still make up the majority of U.S. energy production, are only about twice as efficient today than they were a century ago? Wasn't most of the effort put into making them MUCH MUCH cleaner? I mean, the https://en.wikipedia.org/wiki/Cuyahoga_River doesn't catch on fire anymore, and the amount of https://en.wikipedia.org/wiki/Acid_rain seems pretty tolerable compared to the early…

If you can make a coal plant twice as efficient, you can generate X amount of electricity for half the cost. Adding filters meanwhile just adds cost.

I think both of these things happened, but only one of them is in the interest of a market actor.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#255

Post by trhway »

titanomachy wrote: post #215
nabla9 wrote: post #164

I'm not seeing any top physicists working in this program (McGuire is not one). I would be willing to bet 1000 EUR that their math and modeling does not add up, or they have skipped some details. Problem with fusion research like this is that the closer you get self sustainment or energy generation, the harder it gets and problems pile up. This project looks like many other similar projects that have gone bust. They…

"There aren't any top physicists working on this project" isn't really enough to dismiss it outright. The number of brilliant physicists is much greater than the number of top physicists, so it's not unheard of for major developments to come from someone who's not yet highly recognized. McGuire's an MIT Ph.D, so it's likely he's not a complete idiot. I hope they have some novel ideas about neutron containment, though…

>McGuire's an MIT Ph.D, so it's likely he's not a complete idiot.

obviously. The proposed reactor looks exactly like a great PhD thesis with honors - a novel field configuration proposed which allows to reach beta of one. The rest of the whole system is given only cursory treatment. In particular how about a "neutron absorbing blanket" in a business-jet size envelope?

Re: Skunk Works Reveals Compact Fusion Reactor Details

#256

Post by trhway »

regularfry wrote: post #109
27182818284 wrote: post #42

> could be ready for use in a decade. That's the standard issue joke. "Nuclear fusion has been just ten years away for the last fifty years" It is so common as a joke I'm surprised the article didn't mention it.

What's different this time (yeah, I know, I know) is that, if what they and EMC2 are separately claiming is true, it's gone from being a fundamental physics problem to relatively tractable engineering, with well-understood risks and timelines. Compare this with ITER, where they still don't know what material some fairly critical components can even be theoretically made of. It's just night and day.

>Compare this with ITER, where they still don't know what material some fairly critical components can even be theoretically made of. It's just night and day.

the Skunk Works and EMC2 haven't even reached the stage where they would face the same issue of material - all of them would ultimately have to contain the same type of fast neutrons and there is no good known material to do it.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#257

Post by robotresearcher »

logfromblammo wrote: post #241
rayiner wrote: post #213

Earlier quoted context omitted.

That's hardly ever true. In my experience, Hacker News is full of people from the software field; folks whose professions are often unconstrained by physics,[1] and who have a generally optimistic "this can happen" mentality. That's why everyone here believes we'll have fully self-driving cars in 5-6 years. In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (p…

Physicists recognize the constraints on development imposed by the laws of physics. Software professionals recognize the constraints on development imposed by entropy, information theory, and other esoteric branches of mathematics. Rather than scoff at this article because Lockheed is making extraordinary claims without the backing of extraordinary evidence, I prefer to scoff because nuclear physics modeling and simu…

And yet engineers, including nuclear engineers, very often build stuff that works despite imperfect software.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#258

Post by thrownaway2424 »

Zikes wrote: post #221
guelo wrote: post #210

Earlier quoted context omitted.

If you have to periodically throw away your reactor and buy a new one because of neutron damage that would be a positive thing for a company like Lockheed.

Maintenance costs alone would be astronomically lucrative.

But solving fusion will cut into Lockheed's mainline oil wars revenue stream.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#259

Post by trhway »

revelation wrote: post #254
jfoutz wrote: post #222

Earlier quoted context omitted.

> Did you know that coal plants, which still make up the majority of U.S. energy production, are only about twice as efficient today than they were a century ago? Wasn't most of the effort put into making them MUCH MUCH cleaner? I mean, the https://en.wikipedia.org/wiki/Cuyahoga_River doesn't catch on fire anymore, and the amount of https://en.wikipedia.org/wiki/Acid_rain seems pretty tolerable compared to the early…

If you can make a coal plant twice as efficient, you can generate X amount of electricity for half the cost. Adding filters meanwhile just adds cost. I think both of these things happened, but only one of them is in the interest of a market actor.

>but only one of them is in the interest of a market actor.

it is only until that market actor is allowed to externalize the costs of his pollution

Re: Skunk Works Reveals Compact Fusion Reactor Details

#260

Post by Zikes »

thrownaway2424 wrote: post #258
Zikes wrote: post #221

Earlier quoted context omitted.

Maintenance costs alone would be astronomically lucrative.

But solving fusion will cut into Lockheed's mainline oil wars revenue stream.

That'll do for now, but CFRs are a sustainable strategy that will keep the pensions rolling.
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