• High-gain nuclear fusion shown achievable through simulation
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[release] [TABLE="width: 800"] [TR] [TD][IMG]http://cdn.physorg.com/newman/gfx/news/hires/2012/nuclearfusio.jpg[/IMG][/TD] [TD]Prototype assembly of MagLIF system - the top and bottom coils enclose the lit target. (Photo by Derek Lamppa)[/TD] [/TR] [/TABLE] [/release] [release] [B](PhysOrg.com) -- High-gain nuclear fusion could be achieved in a preheated cylindrical container immersed in strong magnetic fields, according to a series of computer simulations performed at Sandia National Laboratories.[/B] The simulations show the release of output energy that was, remarkably, many times greater than the energy fed into the container’s liner. The method appears to be 50 times more efficient than using X-rays — a previous favorite at Sandia — to drive implosions of targeted materials to create fusion conditions. “People didn’t think there was a high-gain option for magnetized inertial fusion (MIF) but these numerical simulations show there is,” said Sandia researcher Steve Slutz, the paper’s lead author. “Now we have to see if nature will let us do it. In principle, we don’t know why we can’t.” High-gain fusion means getting substantially more energy out of a material than is put into it. Inertial refers to the compression in situ over nanoseconds of a small amount of targeted fuel. Such fusion eventually could produce reliable electricity from seawater, the most plentiful material on earth, rather than from the raw materials used by other methods: uranium, coal, oil, gas, sun or wind. In the simulations, the output demonstrated was 100 times that of a 60 million amperes (MA) input current. [highlight]The output rose steeply as the current increased: 1,000 times input was achieved from an incoming pulse of 70 MA.[/highlight] Since Sandia’s Z machine can bring a maximum of only 26 MA to bear upon a target, the researchers would be happy with a proof-of-principle result called scientific break-even, in which the amount of energy leaving the target equals the amount of energy put into the deuterium-tritium fuel. [highlight]This has never been achieved in the laboratory and would be a valuable addition to fusion science[/highlight], said Slutz. Inertial fusion would provide better data for increasingly accurate simulations of nuclear explosions, which is valuable because the U.S. last tested a weapon in its aging nuclear stockpile in 1992. The MIF technique heats the fusion fuel (deuterium-tritium) by compression as in normal inertial fusion, but uses a magnetic field to suppress heat loss during implosion. The magnetic field acts like a kind of shower curtain to prevent charged particles like electrons and alpha particles from leaving the party early and draining energy from the reaction. The simulated process relies upon a single, relatively low-powered laser to preheat a deuterium-tritium gas mixture that sits within a small liner. At the top and bottom of the liner are two slightly larger coils that, when electrically powered, create a joined vertical magnetic field that penetrates into the liner, reducing energy loss from charged particles attempting to escape through the liner’s walls. An extremely strong magnetic field is created on the surface of the liner by a separate, very powerful electrical current, generated by a pulsed power accelerator such as Z. The force of this huge magnetic field pushes the liner inward to a fraction of its original diameter. It also compresses the magnetic field emanating from the coils. The combination is powerful enough to force atoms of gaseous fuel into intimate contact with each other, fusing them. Heat released from that reaction raised the gaseous fuel’s temperature high enough to ignite a layer of frozen and therefore denser deuterium-tritium fuel coating the inside of the liner. The heat transfer is similar to the way kindling heats a log: when the log ignites, the real heat — here high-yield fusion from ignited frozen fuel — commences. Tests of physical equipment necessary to validate the computer simulations are already under way at Z, and a laboratory result is expected by late 2013, said Sandia engineer Dean Rovang. Portions of the design are slated to receive their first tests in March and continue into early winter. Sandia has performed preliminary tests of the coils. Potential problems involve controlling instabilities in the liner and in the magnetic field that might prevent the fuel from constricting evenly, an essential condition for a useful implosion. Even isolating the factors contributing to this hundred-nanosecond-long compression event, in order to adjust them, will be challenging. “Whatever the difficulties,” said Sandia manager Daniel Sinars, “we still want to find the answer to what Slutz (and co-author Roger Vesey) propose: Can magnetically driven inertial fusion work? We owe it to the country to understand how realistic this possibility is.” The work, reported in the Jan. 13 issue of Physical Review Letters, was supported by Sandia’s Laboratory Directed Research and Development office and by the National Nuclear Security Administration. [/release] [URL="http://www.physorg.com/news/2012-03-nuclear-fusion-simulation-high-gain-energy.html"]Source[/URL] [URL="http://www.sandia.gov/index.html"]Laboratory[/URL]
Awesome, but too bad the world is already too afraid of nuclear power to use this.
[QUOTE=MajorMattem;35278581]Awesome, but too bad the world is already too afraid of nuclear power to use this.[/QUOTE] Nuclear fusion is much safer than fission. It's very delicate, so if you somehow cut the reaction the reactor would quickly decelerate and just stop working, and the worst thing you can get is a small, localized explosion in the reactor chamber (which can be prevented with enough shielding). Compare that with fission, which can accelerate very quickly if left uncooled or unwatched. There isn't even going to be any nuclear fallout or radiation because the materials used aren't radioactive.
simulation
[QUOTE=fekedout;35278774]simulation[/QUOTE] Shows that its possible though.
Finally some good fucking news.
[QUOTE=carcarcargo;35278782]Shows that its possible though.[/QUOTE] i wouldn't get too excited over this though
I've never understood how fusion works, and all the articles I can find are nigh incomprehensible. How does it produce more energy than it takes in?
They pretty much simulate a sun environment right? I have no clue of how this generates energy.
Oh god I'm excited
[QUOTE=QwertySecond;35278838]I've never understood how fusion works, and all the articles I can find are nigh incomprehensible. How does it produce more energy than it takes in?[/QUOTE] Elements lighter than Iron are the only ones capable of generating energy (AFAIK). They do so because when they fuse, a very small amount of mass is lost. For instance: four hydrogen atoms are used to produce a single helium atom in the sun. Hydrogen has an atomic weight of 1.0079 while helium has an atomic weight of 4.0026 Four hydrogens together have a mass of 4*1.0079==4.0316 Note how that mass is different from the atomic weight of helium. Four hydrogens together weigh more than a single helium. 4.0316-4.0026==0.029 That .029 is turned into your energy. That is how it was explained to me anyways.
That's great news! [QUOTE=sami-pso;35278908]They pretty much simulate a sun environment right? I have no clue of how this generates energy.[/QUOTE] Splitting atoms releases excessive energy (Fission) and so does slamming 2 atoms together into one (Fusion). EDIT: Ninja'd.
While this is an amazing discovery, I can't help noticing how slutz is such an unfortunate name.
[QUOTE=QwertySecond;35278838]I've never understood how fusion works, and all the articles I can find are nigh incomprehensible. How does it produce more energy than it takes in?[/QUOTE] The nuclei of atoms are held together by something called the strong nuclear force, fission reactions break these bonds and split up atoms, fusion reactions join them together. The energy needed to make or break those bonds depends on the atom, so splitting uranium 235 produces more energy than it takes to split it, while something like carbon would take more energy to spilt than you'd get out of it. Fusing hydrogen can produce more energy than it takes to make the reaction happen, but we can't build anything capable of it yet.
[QUOTE=QwertySecond;35278838]I've never understood how fusion works, and all the articles I can find are nigh incomprehensible. How does it produce more energy than it takes in?[/QUOTE] [QUOTE=sami-pso;35278908]They pretty much simulate a sun environment right? I have no clue of how this generates energy.[/QUOTE] It's not quite like the sun. We're big on saying "oh yeah stars are nature's fusion reactors" but the methods are way different (for example, stars can take advantage of quantum shenanigans, we can't). The basic principle is somewhat counter-intuitive. People like to think of it like fission in reverse, but in reality, most people don't understand fission either. I'll start with fusion since the basic concept is really easy. [QUOTE=daviddarling.info]A fusion reaction occurs when two light nuclei approach each other so closely that their Coulomb (charge) repulsion is overcome, allowing the nuclei to fuse. [B]The total mass of the fusion products is lower than that of the two original nuclei; the difference is converted to kinetic energy[/B] which is distributed between the products.[/QUOTE] This is true for everything, any fused element is lighter than the sum of its parts. What we're currently trying to do, put as simply as possible, is smash things together via lasers, magnets, or, in this case, lasers and magnets at the same time. If we can reach a break-even point where we spend the same amount of energy smooshing as we can harness from the reaction it causes, we can then start making the process more efficient, and draw energy from the reaction. This should be doable, because these individual small elements are at a higher energy state than more stable, heavier elements, but they're also extremely difficult to work with. [QUOTE=GunFox;35278995]Elements lighter than Iron are the only ones capable of generating energy (AFAIK). They do so because when they fuse, a very small amount of mass is lost.[/QUOTE] Everything is at a lower mass than it would be if it were broken up into individual components. Iron is the boundary line where things are both too stable to split or smoosh. [IMG]http://www.daviddarling.info/images/binding_energy.jpg[/IMG] [QUOTE]The general decrease in binding energy beyond iron is due to the fact that, as nuclei gets bigger, the ability of the strong force to counteract the electrostatic repulsion between protons becomes weaker. The most tightly bound isotopes are 62Ni, 58Fe, and 56Fe, which have binding energies of 8.8 MeV per nucleon. Elements heavier than these isotopes can yield energy by nuclear fission; lighter isotopes can yield energy by fusion.[/QUOTE] Because the forces responsible for binding energy are ranged, larger stuff is subject to a sort of, how to put it, 'bloat' from other forces, that makes it easy to split up.
Thanks guys that actually makes sense to me now.
Simulation, not real. Doesn't matter without the engineering to back it up.
[QUOTE=Used Car Salesman;35280481]Simulation, not real. Doesn't matter without the engineering to back it up.[/QUOTE] The simulation is based on the same equations and laws that are used when dealing with real fusion reactions, don't just discount it because of it being a simulation.
[QUOTE=Used Car Salesman;35280481]Simulation, not real. Doesn't matter without the engineering to back it up.[/QUOTE] Uh, a simulation shows it is possible in real life wit lh the right technology
[QUOTE=Glorbo;35278761]Nuclear fusion is much safer than fission. It's very delicate, so if you somehow cut the reaction the reactor would quickly decelerate and just stop working, and the worst thing you can get is a small, localized explosion in the reactor chamber (which can be prevented with enough shielding). Compare that with fission, which can accelerate very quickly if left uncooled or unwatched. There isn't even going to be any nuclear fallout or radiation because the materials used aren't radioactive.[/QUOTE] Remember who we're dealing with though: [media]http://www.youtube.com/watch?v=XOI-Va5aU3U[/media]
[QUOTE=Azur;35280838]The simulation is based on the same equations and laws that are used when dealing with real fusion reactions, don't just discount it because of it being a simulation.[/QUOTE] That doesn't mean anything. Simulations prove nothing. In this case, they're being used to formulate a hypothesis for some actual experimental work. [QUOTE=the source you didn't read]Tests of physical equipment necessary to validate the computer simulations are already under way at Z, and a laboratory result is expected by late 2013[/QUOTE] [QUOTE=DesolateGrun;35280872]Uh, a simulation shows it is possible in real life wit lh the right technology[/QUOTE] We already [I]know[/I] fusion is possible "with the right technology." This simulation shows something is possible in conditions that [I]might not exist.[/I] He is actually right. Sandia has jumped the gun before, is very eager to play catchup since they're working with a method reactor method. Don't overblow somebody saying "maybe X" as "probably X", they've got a lot to actually show yet.
[QUOTE=Azur;35280838]The simulation is based on the same equations and laws that are used when dealing with real fusion reactions, don't just discount it because of it being a simulation.[/QUOTE] It may be physically possible, but it still doesn't mean we can do it. I really hope we do, but scientists have spent half a century trying to make contained, sustained fusion work.
[QUOTE=OvB;35280891]Remember who we're dealing with though: [media]http://www.youtube.com/watch?v=XOI-Va5aU3U[/media][/QUOTE] [media]http://www.youtube.com/watch?v=xM8E-CogkYE[/media]
[QUOTE=GunFox;35278995]Elements lighter than Iron are the only ones capable of generating energy (AFAIK). They do so because when they fuse, a very small amount of mass is lost. For instance: four hydrogen atoms are used to produce a single helium atom in the sun. Hydrogen has an atomic weight of 1.0079 while helium has an atomic weight of 4.0026 Four hydrogens together have a mass of 4*1.0079==4.0316 Note how that mass is different from the atomic weight of helium. Four hydrogens together weigh more than a single helium. 4.0316-4.0026==0.029 That .029 is turned into your energy. That is how it was explained to me anyways.[/QUOTE] By what you are saying there, if i were to fuse 1 gram of hydrogen to form Helium and energy, i'd get 2.61*10^13 Joules of energy? and if humans were capable of 100% energy capture, that's a McFuckTon of energy there.
[QUOTE=fekedout;35278790]i wouldn't get too excited over this though[/QUOTE] You do understand that scientific simulations use our current scientific laws in the programming so this is entirely possible to achieve, all we have to do is put it into practice really.
[QUOTE=zombini;35284752]By what you are saying there, if i were to fuse 1 gram of hydrogen to form Helium and energy, i'd get 2.61*10^13 Joules of energy? and if humans were capable of 100% energy capture, that's a McFuckTon of energy there.[/QUOTE] He was explaining the principle of how it was done, it wasn't meant to be a detailed essay on the mechanics of nuclear fusion/fission.
[QUOTE=trent_roolz;35284886]He was explaining the principle of how it was done, it wasn't meant to be a detailed essay on the mechanics of nuclear fusion/fission.[/QUOTE] I just wanted to do some math. I was never good at math, but i figured that out pretty well. [editline]25th March 2012[/editline] [QUOTE=trent_roolz;35284886]He was explaining the principle of how it was done, it wasn't meant to be a detailed essay on the mechanics of nuclear fusion/fission.[/QUOTE] Also, it kinda shows just how much energy there really is in matter. I read somewhere that matter is just solid energy that gathered together.
[QUOTE=zombini;35284894]I just wanted to do some math. I was never good at math, but i figured that out pretty well. [editline]25th March 2012[/editline] Also, it kinda shows just how much energy there really is in matter. I read somewhere that matter is just solid energy that gathered together.[/QUOTE] Yeah matter is essentially just "condensed" energy in a sense, that's why you can directly convert matter into energy through fusion and fission. Also we'd never be able to get that much usable energy cause a sizeable portion of the energy released in fusion and fission is released as heat and we have major issues trying to harness heat.
[QUOTE=GunFox;35278995]Elements lighter than Iron are the only ones capable of generating energy (AFAIK). They do so because when they fuse, a very small amount of mass is lost. For instance: four hydrogen atoms are used to produce a single helium atom in the sun. Hydrogen has an atomic weight of 1.0079 while helium has an atomic weight of 4.0026 Four hydrogens together have a mass of 4*1.0079==4.0316 Note how that mass is different from the atomic weight of helium. Four hydrogens together weigh more than a single helium. 4.0316-4.0026==0.029 That .029 is turned into your energy. That is how it was explained to me anyways.[/QUOTE] That seems sketchy because the standard mass on the periodic table is made by an average of the proportion of the isotopes, which is why apparently tellurium weighs more* than iodine even though iodine is just to the right of tellurium, but it's just because the average proportionality of the tellurium isotopes give you a bigger number than iodine's. So that explanation just seems wrong. *reffering to the standard atomic mass on the periodic table
[QUOTE=Kendra;35285716]That seems sketchy because the standard mass on the periodic table is made by an average of the proportion of the isotopes, which is why apparently tellurium weighs more* than iodine even though iodine is just to the right of tellurium, but it's just because the average proportionality of the tellurium isotopes give you a bigger number than iodine's. So that explanation just seems wrong. *reffering to the standard atomic mass on the periodic table[/QUOTE] But here he's not referring to the average atomic mass you get on the periodic table, it's the actual mass of a certain isotope. The atomic mass unit u is defined to be 1/12th of mass of carbon 12. Only carbon 12 has the mass of exactly 12u, for other elements it's not exactly the same as number of nucleons * u due to binding energies involved.
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