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Boeing Patents an Engine Run By Laser-Generated Fusion Explosions
MarkWhittington writes: Boeing has had a patent approved for an aircraft engine that uses laser-generated nuclear fusion as a power source, according to a story in Business Insider. The idea is already generating a great deal of controversy, according to the website Counter Punch. The patent has generated fears of what might happen if an aircraft containing radioactive material as fuel were to crash, spreading such fuel across the crash site.
Fusion doesn't use any.
Now we won't have laser ignited fusion powered aircraft for another 20 years.
Once again we have a patent issued for something that wasn't built, can't be built and likely will never be built. Boeing has no idea how to build a fusion engine, and if they could then they could and should build a ground based fusion power plant based on their magic technology. About the only thing that can ever happen with this patent is to be used by a troll in case anyone does really manage to build a fusion power plant that uses some of the same terms used in this science fiction document, such as lasers.
I'm an American. I love this country and the freedoms that we used to have.
But the plutonium produced by firing neutrons into it is.
If it's fusion as opposed to fissions wouldn't the fuel be some hydrogen isotope?
Tea and kung-fu. Life is good. Rising Phoenix
People worrying about some very short half-life Helium really, really have no clue what they are talking about. Just have a look at what gets _shipped_ in radioactive materials all the time, and there you may find something to worry. Or not, if packed properly.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
The moment the word "nuclear" is mentioned people go crazy. This is fusion where tritium pellets are bombarded with lasers to fuse into helium. The concept works in the lab, but the the amount of energy generated is pretty low when compared to the energy required to drive the lasers. It is NOT fission, the process used in current nuclear power plants where uranium or plutonium is split into radioactive particles with long half lives. Chances are pretty good that this patent will expire well before the process becomes viable (if this ever occurs). Yawn!
The fusion is used to generate electricity. It still uses a turbine.
.: Semper Absurda
I can't imagine the actual technology is real, but apparently the interest is real enough.
You're mistaking deuterium (H^2) for tritium (H^3), which is still the wrong thing to be looking for. Lunar regolith is frequently cited as a source of He^3 (Helium-3), which in some schemes would be a suitable fusion fuel, but Helium-3 fusion is so difficult to initiate and keep stable that it's just stuff of pure science fiction (I mean the fusion bit is science fiction, the Helium-3 part is real enough).
If you want to absorb neutrons you use parafin, not u238. U238 is quite picky about the neutron energies it will absorb, and the rest pass right through. Hydrogen (as in parafin) is a lot more willing to accept different energies. So if you wanted to use neutrons from a fusion reaction to energize U238 you'd probably need to run it through a moderator...probably either graphite (think Chernobyl) or heavy water.
That doesn't sound like a good airplane engine to me.
I think we've pushed this "anyone can grow up to be president" thing too far.
U238 will happily absorb neutrons (which are produced by the fusion) and become U239. U239 will happily absorb beta radiation (also production by the fusion) and become Np239. Np239 will also happily absorb beta radiation and become Pu239. Pu239 is nasty stuff that you don't want to get anywhere near you.
This is in fact exactly the reaction used in the production of Pu239 for nuclear weapons.
It's not an "aircraft engine". You can look at the patent yourself.
It's an open-cycle nuclear rocket engine that sprays fusion neutrons and tritium all over the place and has no significant containment for neutron-activated materials or fission fragments. OF COURSE it's not for use in Earth's atmosphere.
This is a made-up story. The jet-engine-shaped diagrams in the press are not in the patent.
Not THAT kind of turbine (although you could rig it that way - very Rube Goldberg). It uses hot exhaust gas (non radioactive so it isn't at all like Orion like TFA intimates) to directly push the aircraft (or rocket or what have you) in an equal and opposite direction.
Faster! Faster! Faster would be better!
This is in fact exactly the reaction used in the production of Pu239 for nuclear weapons.
Cool. Portable nuclear proliferation. Now that's progress.
Faster! Faster! Faster would be better!
How can you patent something you can't even get working? That's grade A #1 BULLSHIT!
First lithium-ion battery fires, now this. What could go wrong?
It must have been something you assimilated. . . .
So, if we can get this to the right scale; we can have a 'sustainable bomber' capable of all steps from enrichment to warhead delivery! It's like a seat on the security council in one convenient package.
From a fictional engine that doesn't exist and won't exist until we actually have practical fusion.
Really this is what is wrong with the patent system. Now anyone developing engines using any kind of fusion is going to have a visit from Boeings lawyers over something they have done nothing to make work.
CounterPunch is a monthly magazine published in the United States that covers politics in a manner its editors describe as "muckraking with a radical attitude".[1] It has been described as left-wing by both supporters and detractors.[2][3][4]
This magazine is about as merely "left-wing" as the Death Valley in Mojave is merely "warm" in the summer.
"Politicians and diapers must be changed often, and for the same reason."
The basic concept is similar to Freeman Dyson's Project Orion https://en.wikipedia.org/wiki/... which makes any patent subject to prior art claims. If they're patenting a specific technique, then good for them!
Fuzz, I'm surprised you never heard of this...
It is pure fiction. As in: has been talked about for years but nobody can actually get it to work.
Patents like this are a travesty and a long lineup of attorneys and examiners should be ashamed of themselves.
Bent, folded, spindled, and mutilated.
Not to mention that there's tons of ways to make 3He here on Earth. Including the natural decay of tritium.
The human body can be drained of blood in 8.6 seconds given adequate vacuuming systems.
So many terrible mistakes...
Deuterium and tritium are not in fact "fissile material", but are inert, non-radioactive materials. The "pellets" are cryogenic hydrogen gas isotopes fond in natural hydrogen.
Fusion is the opposite of fission, and while it's a nuclear process.
The U-238 that they would line the engines with is *also* not "fissile", and is not radioactive (the radioactive isotope is U-235), and is used for neutron absorption from the fusion process to turn the neutrons into heat so that no one is exposed to fast neutrons.
Note that these are *FAST* neutrons; to turn U-238 into Pu-239 requires *SLOW* neutrons. Even if some idiot put the one foot of paraffin required into the combustion chamber between the U-238 and the fusion reaction, it'd be burn out immediately by the temperatures involved (which is why we use reactor reactors to make Pu-239, and not straight Beryllium/Polonium or other less conventional neutron sources).
Basically, if one of these crashed, it would result in a bunch of inert wreckage, just like any other plane crash, although instead of starting a fire or anything, the pellet storage, if breached, would boil off (meaning the hydrogen isotopes would "heat" up to the point they became gas, not that anything would be hot).
In other words, no radiation anywhere.
P.S.: To the idiots who claim "this is how we make Pu-239 today" -- no, we do not use neutrons from fusion reactions to make Pu-239; also, if it were that easy to make Pu-239 *on purpose*, as opposed to *as a by-product of a design intended to avoid its production entirely*, Iraq would have had nuclear weapons already.
Well, if you want to absorb neutrons, you want a neutron poison like boron. If you want to moderate them, you want something rich in some combination of hydrogen (most effective, but too capture prone for some needs), deuterium (pretty good at moderating, extremely low capture, very expensive), helium (zero capture, fairly expensive, not a very efficient moderator, esp from a volume perspective), carbon (pretty low capture, fair at moderation, cheap, but need to avoid buildup of wigner energy), or oxygen (quite low capture, cheap, but subpar at moderation).
The human body can be drained of blood in 8.6 seconds given adequate vacuuming systems.
"Not radioactive"
Not true.
It's an alpha emitter with a half life of 4.5 billion years.
ICF has already been demonstrated to work, however the laser density and strength has limited the efficiency. Perhaps the "Rocket City Rednecks" can bust out their weaponised blu-Ray player arrays and put them to a peaceful purpose.
So many more mistakes:
Tritium is indeed radioactive with a half life of about 12.5 years (That's why it's great for making glow in the dark dials that require no light recharging or electricity. Only a tiny amount is needed, but a 12.5 year half life is pretty darn "hot" in the vernacular, and if you have a lot of it, you get a lot of energy release. It emits beta rays (high energy electrons) which aren't as much of a problem as gamma, but do cause surface burning, etc.).
U238 is indeed radioactive. It's an alpha particle emitter with a half life of 4.5 billion years. (Agreed, it's not highly radioactive, but it certainly is radioactive. U235 is more highly radioactive.)
I'm hardly an alarmist about nuclear technology and am a strong supporter of nuclear power, but blatant mistakes in your post don't help the argument in favor of it.
But what about Alienware computers?
I'm not saying it's aliens, but...
Probably a naive question, but isn't u238 the non-fissionable isotope of uranium? It sounds like it's chosen because it's one of the few superdense materials we have access to, to limit the thickness of the shielding needed to absorb the energy from the neutrons.
It depends on the energy of the neutron. Slow neutrons are reflected by U-238, which is why it is used as a tamper in nuclear weapons. Higher energy neutrons are absorbed by U-238 to lead to a transmutation to the toxic and explosive Pu-239, ala breeder reactors. With really really high energy neutrons, like you might get from a fusion reaction, U-238 will undergo fission just like its less stable 235 cousin.
If I understand correctly, any element heavier than Fe can be made to undergo fission with a powerful enough neutron bombardment.
Take it easy, Charlie, I've got an Angle...
Here is the actual patent:
http://pdfpiw.uspto.gov/.piw?P...
It's almost gibberish. It's full of sentences like (and I'm quoting)
"Alternatively, when propellant 18c of FIG 4 is utilized in the embodiment of FIG 1, the laser system 22 of Fig. 1 may comprise one or more free-electron lasers for providing pulsed laser beams to vaporize, using pulsed laser beams, pellets each comprising the propellant 18c of Fig 4."
Fig 1 is basically the drawing from the Business Insider article with the parts numbered. Fig 4 is a circle.
Or, it suggests we can use "light-emitting diode (LED) driven Alexandrite lasers" instead of free-electron lasers.
Or maybe a flash lamp driven ruby laser. No kidding.
And then the patent says that the fast neutrons from the Deuterium-Tritium fusion will cause the U-238 to fission and explode.
Again, quoting from the patent:
"The secondary explosion recompresses more of the Deuterium and Tritium, causing more fusion energy to be released beyond the 'breakeven' level vaporizing the remaining pellet materials of the propellant 18c of FIG 4 and increasing the overall thrust and exhaust velocity. Use of this embodiment reduces exhaust molecular weight, and increases exhaust velocity and specific impulse."
I did not mistype that.
I'm wondering how large it will be.
AFAIK, this is what a laser fusion device looks like, except that this one isn't ready for prime-time.
https://lasers.llnl.gov/media/...
Nor this one:
http://www.washington.edu/news...
http://www.washington.edu/news...
I would go with the free-electron laser because this is clearly an attempt to make the largest possible engine for the least thrust.
Also, looking at the diagrams in the article, I don't see anything that suggests they've addressed the problem that hitting the pellet with a laser on one side simply causes the pellet be vaporized and driven away without fusion (somewhat like squeezing a watermelon seed). How can they grant patents from devices that cannot work as designed?
Probably a naive question, but isn't u238 the non-fissionable isotope of uranium? It sounds like it's chosen because it's one of the few superdense materials we have access to, to limit the thickness of the shielding needed to absorb the energy from the neutrons.
U-238 is fissionable with fast neutrons. Fusion reaction produce fast neutrons.
In this patent, they say they hope that the laser-induced fusion of the pellet would create fast neutrons that would in turn cause fission in the U-238, thus boosting the energy output.
This is how modern so-called hydrogen bombs work. A fission bomb surrounds a core of fusionable material (deuterium and tritium etc). The fission bomb compresses and causes fusion of the light-element core. The bomb is encased in a jacket of U-238. The fast neutrons released by the fusion make U-238 fission. Because U-238 has no critical mass (and won't support chain reactions), you can layer on all you want. Most of the power does NOT come from energy released by the fusion component - it's job is to make fast neutrons to fission the U-238 jacket
U238 is only used as the outer 'shielding' of Nuclear weapons as it when does absorb neutrons that are generated by the bomb detonating it creates a cascade of more neutrons generated than the just one that hit it, some of which go back toward the Lithium 6 Deuteride inner 'shielding'. This essentially 'reflects' neutrons back into the core, which can significantly increase the yield of a nuke. The Lithium 6 Deuteride is responsible for the 'Fusion boosted' part. The U238 just 'prevents' some of the neutrons from 'escaping'.
The technical term is neutron cross section: https://en.wikipedia.org/wiki/...
I art more snarky, and terse than thou. I art Slashdot!
Boronated parafin. Parafin by itself doesn't do much. It's the Boron that has the high 'neutron cross section'
I art more snarky, and terse than thou. I art Slashdot!
Pu239 isn't really all that nasty in smallish quantities. The half life is large at over 24,000 years. It is Alpha decay (a helium nucleus, which is effectively stopped by the dead layer of skin on our bodies.) It only becomes an issue when it is near a source of neutrons, since it will 'respond' by generating a cascade of many more neutrons than each one that is absorbed.
It's natural decay can provide this source of neutrons hence you don't want to be near a large of enough quantity of it, as it will be generating a lot of neutrons from the 'chain reaction'.
So if all of it is in a sphere in the middle of the room, stay the hell away from it. If the same quantity is scattered as shot across the floor, it's not such an issue.
I art more snarky, and terse than thou. I art Slashdot!
Iron is the most stable nuclide (with Nickel being a close second), so creating elements above them requires energy. Not all heavier elements are radioactive though. The higher the ratio of neutrons to protons, the more likely the element is to be radioactive. There are so called 'islands of stability', just like with electron shells. Then there are also the double magic nuclei. I think that effect is the most interesting thing I have seen in all of Physics:
https://en.wikipedia.org/wiki/...
One of those higher magic numbered nuclei (elements we have not detected yet) are probably the fuel that the Annunaki used in their spaceships to enslave humanity 241,000 years ago...Just sayin.
I art more snarky, and terse than thou. I art Slashdot!
By far the majority of the power comes from the Lithium 6 Deuteride fusion booster, that sits between the U238 outer shell, and the actual core. The U238 helps, but it is not the most significant boost. The U238 is actually meant to create more neutrons in order to seed more Fusion; so that not as much of the fusion 'fuel' is lost to the explosion. I suspect it was also because after enrichment they have all of this 'depleted uranium' lying around, so why not put it to good use? It may only be a 40% boost (I don't know the actual number), but it is free!
I art more snarky, and terse than thou. I art Slashdot!
"Practically Not radioactive"
FTFY
I art more snarky, and terse than thou. I art Slashdot!
LLNL scientists have a lot of patents on various parts of the NIF. This Boeing patent references some of them. The patent describes the lasers, hohlraum, DT pellets, etc.
In a way, they've cut the NIF chamber in half, and converted one half into a nozzle. Fig 1, 5 of the patent illustrate the classic spike and bell nozzles, respectively.
The design really seems like a novel adaptation of the NIF effort.
"If you can dream it, you can do it"
-- Walt Disney
Then again, all three scientists are from Southern California, the land of $ 60 recommendations and a sea of dispensaries.
Actually this is more like Project Daedalus in that it uses ICF to a degree.
No way this is going to work with current materials. ICF is low density and there are no lightweight low-volume radiation shields available.
The original fission powered proposals from the 1950s-1960s have more of a chance to actually work. This proposal is a Rube-Goldberg contraption.
I don't see anyone outside of the US military using it... and even them using it is a stretch.
Short of that... Nope.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
Yes it is, it has a half life of 4.468 billion years and undergoes alpha decay.
I've heard of lasers used in high gap distance spark plugs. They're supposed to ignite more fuel faster than high voltage electrical sparks but I have my doubt. But seriously, fusion?! You lose magnetic containment for one second and that engine blows apart. Worst idea ever.
How are they going to suspend the sharks on the wings?
But do you need to pay royalties if you're only doing R&D?
Oh, you're right. The first link makes that clear.
.: Semper Absurda
Unless there's some sort of game they play with "continuations" of patents to keep them going forever (like at least one of the remaining patents around .mp3 encoding) it seems like most of these sorts of patents should expire before there's even a working prototype. Is this just parasitism by company IP lawyers and associated corporate baggage trying to justify their pay?
(From the link above:)"This application is a continuation of application Ser. No. 08/650,896, filed on May 17, 1996, (now abandoned) which was a continuation of application Ser. No. 08/519,620, filed on Sep. 25, 1995, (now abandoned) which was a continuation of application Ser. No. 07/977,748, filed on Nov. 16, 1992, (now abandoned), which was a continuation of application Ser. No. 07/816,528, filed on Dec. 30, 1991, (now abandoned), which was a continuation of application Ser. No. 07/640,550, filed on Jan. 14, 1991, (now abandoned), which was a continuation of application Ser. No. 07/177,550, filed on Apr. 4, 1991, (now abandoned) as international application serial No. PCT/DE87/00384, filed Aug. 29, 1987, claiming priority to foreign appl. No. P3629434.9, filed Aug. 29, 1986."
Hacker Public Radio is our Friend
I think you misread something. Pu239 synthesis doesn't include beta capture. U239 is unstable and EMITTS a beta similarly for Np239. Beta (electron) capture would lead to a lower atomic number:
P+e^- = N+\nu_e
There used to be a cool webpage where you could traverse all the isotopes and see how they were produced but I can't seem to find it now.
The article says the patent specifies deuterium or tritium. Only if the engine uses tritium will there be any radioactive fuel to be spread.
Alpha emitters are harmless outside the body, but inside the body they're far worse per unit decay energy than beta or gamma emitters. Read about how ridiculously dangerous polonium 209 is, for example - there's a reason it was chosen by the Russians as an assassination tool. Even with orders of magnitude higher half life than 209Po, 239Pu is still very dangerous if ingested or inhaled. If you had some "scattered as shot across the floor", you're making an inhalation hazard.
The human body can be drained of blood in 8.6 seconds given adequate vacuuming systems.
Not exactly. 62Ni has a higher binding energy per nucleon than 56Fe. The misconception exists because not much 62Ni is produced in supernovae while large amounts of 56Fe is; for the most part, 56Fe represents the highest binding energy reached in a supernova..
The human body can be drained of blood in 8.6 seconds given adequate vacuuming systems.
This kind of patent on a general concept acts as a string disincentive to others to invest the resources needed to turn such concepts into practical implementations. Usually, that is undesirable. In this case, some seem to believe strongly that the concept should not be pursued. These people should be celebrating.
This thing is going to be kicking out probably hundreds of kW to maybe MW of neutrons with passengers a few meters away.
http://talk-polywell.org/bb/vi...
Could you be thinking of this one? http://nucleardata.nuclear.lu....
https://en.wikipedia.org/wiki/...
Project Pluto was supposed to be used on Earth. You know, if the Americans can't have it, then at least the commies wouldn't have it, either.
https://en.wikipedia.org/wiki/...
Reason why he posted as AC. He's full of it. It has a half life and is radioactive. I'd offer to put a half Lbs under his pillow and dare him to keep it there for half a year. He won't be around anymore. It's not like you're going to die within an hour radioactive. It's still "hot". I think I still have some dishes around that are "hot".
1) Fusion powered airplanes; right /. makes a comment about how some other group of people are stupidly wasting time on some idiotic idea....
anytime anyone on
2) Garbage patent
to secure a patent,the invention has to be "enabled"
3)counterpunch is the absolute bottom of the barrel in webcrap
if you can't write, and you have a particularly stupid piece of inane word salad you want on the web, counterpunch is where you would go after your essay was rejected by everyone else (ok National Review on line and Mark Levin are worse, but they are both pathological)
Sorry, but for a moderator you don't want to absorb the neutrons, you want to slow them down. So scratch the boron.
I think we've pushed this "anyone can grow up to be president" thing too far.
There are quite a few worthy fusion/fission-related comments to this article, but it seems that certain idea is not completely clear to everyone: we haven’t ever built a working fusion reactor. Currently there is a (theoretically) serious attempt which is supported by various countries (and by lots of money) call ITER; although it is still a mere theoretical prototype. In fact this project has been systematically delayed during the last years.
A quick overview of how this reactor is expected to work:
1. Reaching an extremely temperature (i.e., the one in the sun), which will instantaneously melt any known material.
2. Containing the aforementioned hot plasma (i.e., self-sustained fusion chain reactions) with magnetic fields and with a very efficient refrigeration system.
3. Getting just a tiny fraction (i.e., what is required to boil water) of all this heat to generate electricity.
Thus, the main problem is that the required heat (the energy used to provoke the first fusion reaction) is so high that provokes quite a few other problems, like confining the hot plasma and extracting only what is required or even having a device able to generate so high temperatures
All these problems are logically much less relevant at much smaller scales (at the microscopic level), where the only successful fusion reactions have precisely occurred; and even at that tiny level, it is very difficult to create a self-sustained reactions generating more power than what is being put in (to not mention all the aforementioned issues associated with so high temperatures).
I have proposed an example in one my comments above which I will repeat here: looking forward to getting any reliable reference to a single successful experiment creating a macroscopic-relevant fusion reaction, like heating a cup of coffee during 5 minutes. I think that such a thing hasn’t ever occurred, but I would love to be proven wrong. Please, provide relevant references to support all your claims on the can-be-done front.
Custom Solvers 2.0 = Alvaro Carballo Garcia = varocarbas.
> if an aircraft containing radioactive material as fuel were to crash, spreading such fuel across the crash site
Everyone knows how dangerous deuterium can be. Why it's one common component in dihydrogen oxide, which kills more people every year than any other chemical substance ever invented. http://www.dhmo.org/facts.html
By far the majority of the power comes from the Lithium 6 Deuteride fusion booster, that sits between the U238 outer shell, and the actual core. The U238 helps, but it is not the most significant boost. The U238 is actually meant to create more neutrons in order to seed more Fusion; so that not as much of the fusion 'fuel' is lost to the explosion. I suspect it was also because after enrichment they have all of this 'depleted uranium' lying around, so why not put it to good use? It may only be a 40% boost (I don't know the actual number), but it is free!
You are right and I was wrong when I said: "Most of the power does NOT come from energy released by the fusion component ". I was talking off the top of my head from what I remembered from Richard Rhodes books. That only describes certain older weapons.
So, I do more reading. Proportion of yield depends upon design (duh), and in modern weapons (such as W-80 and W-88) it's closer to 50/50 fusion/fission contribution to energy.
Anyway, the li6 deuteride and U-238 work together. Both are critical to making the secondary stage work. The Li6-D provides fast neutrons to fission the U-238, and the U-238's fission's neutrons converts the Li6 to tritium for fusion and both boost the yield. The primary fission device has a yield of only 5-10 kT, so most of the yield comes from the fusion-fission secondary stage.
Although the hydrogen isotopes fusion provides more energy per weight, the U238- fission provides 8 times more energy per volume than the fusion component. In most modern weapon delivery systems, the size is more important than the weight.
Also, it appears that now-a-days the US is using highly enriched uranium, HEU, instead of natural U-238 for additional yield-boosting.
the dumb greenpeace moron in the article is comparing the Solar Impulse 2 to a real engine that could power an airliner... Solar Impulse 2 can barely lift itself and a pilot, how is that supposed to support a big jumbo jet with 300 passengers and/or cargo... Solar energy is far from viable (at the moment/decade) for use in commercial flight..
Also nowhere is mentioned that the engine is actually going to be used in commercial flight...