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Skunk Works Reveals Compact Fusion Reactor Details

aviationweek.com

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Re: Skunk Works Reveals Compact Fusion Reactor Details

#161

Post by ufmace »

danbruc wrote: post #153
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…

The Bugatti Veyron 16.4 has 1200 hp and therefore probably produces around 2.5 MW waste heat at full power. A factor of 40 is still quite a difference but it does not sound like an unsolvable problem.

That's peak power, though. Basically no street car is designed to be able to produce peak power for more than a minute or two at a time, and probably very few can do it for more than a few seconds. I'm pretty sure that car doesn't have the cooling capacity to cool itself at full power like this plant would have to.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#162

Post by nether »

sounds wrote: post #132
nerdy wrote: post #70

I know there are some very smart people at skunk works who've done incredible things in the past but humans have cried wolf so many times on fusion it's sort of hard to just accept until they've actually built a working reactor, shown it and had it independently verified.

This is a very good point. Extraordinary claims... If you haven't hung around talk-polywell.org before, you might want to. It's focused on the polywell but they seem to at least try to fairly evaluate all contenders. New confinement techniques (NIF, this article, Helion, Polywell) are actually making real progress. So it's becoming less likely that an announcement like this is 100% vapor. Put another way, we're getti…

The AviationWeek article even mentions that the LMSW team drew from Polywell:

> "We also have a recirculation that is very similar to a Polywell concept," he adds, referring to another promising avenue of fusion power research. A Polywell fusion reactor uses electromagnets to generate a magnetic field that traps electrons, creating a negative voltage, which then attract positive ions. The resulting acceleration of the ions toward the negative center results in a collision and fusion.

It's great that they've scoured even the non-mainstream ideas and incorporated them.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#163

Post by nether »

charlysisto wrote: post #133
nerdy wrote: post #70

I know there are some very smart people at skunk works who've done incredible things in the past but humans have cried wolf so many times on fusion it's sort of hard to just accept until they've actually built a working reactor, shown it and had it independently verified.

I followed the ecat ( http://ecatnews.com/ ) story for a year or so until my BS alarm started getting really loud - but just the prospect of it was so exhilarating, it was hard to resist the enthusiasm overflow... Now this sounds way more serious than Andrea Rossi's saga. But I did get a lot tougher on my wait and see stand.

I'm still waiting on a Steorn Orbo replication...

Re: Skunk Works Reveals Compact Fusion Reactor Details

#164

Post by nabla9 »

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 start by solving the easiest problems first, get some funding and hit the wall.

The main problem with any reactor design is how to handle the 14 MeV neutrons produced by the fusion reaction (no mention in the article). They tend to damage the reactor and make it economically unfeasible. At this point being able to create fusion reaction is not the main challenge. It's the sustainment and economics of limiting the damage. If they really have solved all the problems and demonstrate economically sound fusion in 5-10 years, they will be handed Nobel price in physics for sure.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#165

Post by ufmace »

DubiousPusher wrote: post #147
jeffreyrogers wrote: post #141

Earlier quoted context omitted.

I think you could make the argument that fusion is more or less feasible if someone would just get around to building it too...

I don't believe this is the case. I'm pretty sure there have been "hard" limits so far on what can be achieved. I'm not a physicist, not even close but as I understand it two issues remain. One is that sustaining the fusion reaction has been problematic. I believe the longest sustained reactions have been less than one second. Two is that currently we have to put more energy into creating and sustaining the reaction…

One of the problems with creating longer-running fusion reactions is that if they do it, in order for the reactor to not wildly overheat almost instantly, they need a massive cooling system to carry the generated heat away. At that point, you almost might as well hook up a steam turbine loop and generator and put the power on the grid.

There's lots of other problems too - I don't think they have a well-tested solution for adding fresh fuel and disposing of the fused products on an ongoing basis.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#166

Post by ordinary »

TeMPOraL wrote: post #140
thrownaway2424 wrote: post #134

Earlier quoted context omitted.

This is HN. If the hyperloop was a technological breakthrough, so is this press release.

Hyperloop case doesn't have 50 years of track record of being "just few years from now", and as far as I remember, the design was more-less feasible if only someone would get around to building it. It didn't have such hard problems to be solved as fusion still has.

This is an enlightening explanation: http://www.chforum.org/scenario2012/paper1-4-1.jpg

Re: Skunk Works Reveals Compact Fusion Reactor Details

#167

Post by cjslep »

3pt14159 wrote: post #158
zamalek wrote: post #152

Earlier quoted context omitted.

> Hyperloop case doesn't have 50 years of track record of being "just few years from now" There have been steady incremental advancements in the field. I think your knee jerk reaction is coming from "cold fusion" which does have the problems you are talking about. Two very different fields. The main issue with fusion is that it can't be weaponized and therefore doesn't have a nice military grant behind it. It lacks a…

It already has been weaponized, in the form of a fusion bomb.

zamalek probably meant to refer to the waste products from fusion not being a proliferation concern.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#169

Post by Igglyboo »

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.

The fusion guys should have a meetup with the desktop linux guys.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#170

Post by [deleted] »

danbruc wrote: post #153
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…

The Bugatti Veyron 16.4 has 1200 hp and therefore probably produces around 2.5 MW waste heat at full power. A factor of 40 is still quite a difference but it does not sound like an unsolvable problem.

[deleted]
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