I've heard of tokomaks and ITER but I never heard of a stellarator or the fact that a large prototype was constructed till now.
Can someone briefly explain how this differs from the tokomak in ITER and what the Wendelstein-7X will accomplish for fusion research?
You have to twist plasma so that it won't collide with the walls. Tokamaks do this by inducing currents into a plasma. This is difficult, and if the plasma get's fucked(which fucks up the currents that stabilize everything), you reactor can get rekt. It's also not a continuous process to set up these currents, which makes it possible for there to be instabilities that can wreck everything.
Stellarators put this twist in with geometry avoiding these problems at the expense of making the reactor hell to build. They also can operate continuously which is cool.
It will demonstrate if the plasma physics works or not. They might just discover a brand new plasma instability though...
The main advantage of stellarators over tokamaks is that stellarators don't have to balance some unstable internal-current self-containment craziness that can blow up on you and wreck your reactor. The big disadvantage is that they're structurally more complex and therefore more difficult and expensive to build correctly, which slows down development.
Basically, we know stellarators can work if we scale them up enough and build them precisely enough, but they'd be more expensive than tokamaks. Tokamaks would be cheaper but we don't know if there's actually a way to make them work without making them into stellarators.
Ah so those are some pretty good advantages then, hell of a bitch to build, not surprised it was GERMAN ENGINEERING that got the job done
Will be cool to see what results they get, thanks for explaining the twist thing.
>>but its nowhere near as bad as a fission reactor meltdown right?
Yup, it's just gonna be really expensive to fix. ITER plans to prevent getting totally rekt by shooting snowballs into the plasma to shut everything down.
>I was thinking tokamaks were totally safe, had no idea they have a chance to get fucked, but its nowhere near as bad as a fission reactor meltdown right?
With a tokamak, there's no danger of a runaway reaction, and there shouldn't be a lot of decay heat to melt stuff and start fires.
The main dangers would be for a loss of plama containment to damage the inner wall badly enough that extensive repairs would be needed, or for the superconducting coils to dump their energy into the cryocoolant causing an explosion when it boils. An explosion could also be caused by steam pipe breakage, as in any steam turbine power plant.
There would be a significant inventory of radioisotopes, between the tritium fuel and neutron-activated structural material, which you wouldn't want to leak outside, but it seems relatively easy to build a containment structure which could take even the worst case explosion.
Mostly, you'd just be worried about damaging the reactor, and harming workers, not any sort of widespread destruction. Still, a large tritium leak wouldn't be good.
>the computer needed to render that CAD drawing
quallities of stellarators that tokamaks dont have:
no ExB drift or subsequent plasma centerline shift
steady state operation
operation without plasma current
FRCs are still superior, with closed toroidal magnetic geometry on the inside and open linear magnetic geometry on the plasma exterior, allowing for direct conversion without an additional physical divertor mechanis. also FRCs have high beta values, force-free equilibrium, and fewer MHD instabilities. also applications to propulsion systems
FRC > stellarator >> tokamak
It's also lots of measuring equipment as it's a science reactor that's still too small to generate more power than it consumes but sufficiently large to study all the phenomena that occur in a big one.
It's not that simple. FRCs, like tokamaks, depend on internal currents which can be disrupted by minute perturbations and the energy releases of fusion.
>Basically, we know stellarators can work
...and we don't know if FRCs can. FRCs assume a deeper understanding and more clever exploitation of plasma physics than tokamaks. They're not a new idea, they've been around since the 50s.
It's not far away from where I live. I've been there with some other physics students. They lectured some basic stuff about this machine and showed us the whole complex building. >>7634458
Maybe I should point out a misconception. No fusion reaction will happen inside it hence no energy is produced. It's much to small to reach the necessary temperature. It's just all about observing the plasma.
>No fusion reaction will happen inside it hence no energy is produced.
I expect some fusion will happen inside it. They've made a deliberate choice to use light hydrogen and deuterium rather than deuterium and tritium, to minimize fusion.
This means they don't have to acquire and deal with radioactive tritium, and they don't have to build the thing to stand up to an intense neutron flux.
>It's much to small to reach the necessary temperature.
Come on, now. You can reach the necessary temperature in something the size of a lightbulb.
What it's inadequate for is ignition: the conditions under which fusion will continue without any external heating input.
you cant lie this is getting so much manstream interest mainly because of how it looks. Same reason why tokamaks always get way more media airtime than whatever the laser version is called.
How are we harnessing the energy being produced, steam?
Yes, although any charged particle products can be used for direct electrical conversion. Since 80% of the fusion energy for deuterium-tritium fusion reaction is in the form of neutrons, though, thermal power is the only option until we git gud enough at fusion that we can start thinking of superior but more difficult reactions.
I hope you meant "I expect_ed_". I got my information from a real expert who works there. I even asked him, wether they could improve it in the future and he denied. I suppose they are not able to contain that hot plasma, although it would be not that hard to produce it. That's just a guess.
He probably meant that the plasma wouldn't ignite (which no device has been able to do so far). But W7x will definitely produce fusion for short periods of time (like a few seconds), just like smaller devices are able to (having periods of unsustainable fusion is no big deal, by the way).
But yeah, W7X is more of a wide-ranging, exploratory experiment and doesn't necessarily seek to do fusion for the sake of fusion.
there will def be fusion. no ignition but def fusion. even at lower temps, there will be some amount of the plasma at suitably high temperatures for fusion to occur just look at the boltzmann distribution.
> and doesn't necessarily seek to do fusion for the sake of fusion.
So is this article in the wrong then?
on the subject of fusion, what's /sci/ think of my artistic interpretation of an FRC plasma
Well it's largely expected to bring vital insights in magnetic confinement methods. Hell, DEMO (ITER's successor, a real powerplant prototype) might as well be stellarator- than tokamak-based. I was just refuting the fact that the W7X's goal is to produce actual fusion power (as in ignition). Like JET, it is an experiment, not a powerplant prototype (a misconception many people seem to hold).
Doesn't mean I'm not exited as fuck.
Yes, your point being ?
I mean, W7X will be a bit like JET in terms of "groundbreakingness", but keep in mind that W7X is still a much smaller device than JET (30 cubic metres vs 100 cubic metres of plasma).
meaning just because theyre doing plasma experiments to identify plasma instabilities, test diagnostics systems, etc, doesnt mean theyre working with cold, low density plasmas, or collisionless plasmas that wont be undergoing fusion
Cool, it's nice to see the MPG getting the recognition it deserves
>"This institution, with its many component facilities, is a heavy hitter in the physical sciences, with the fields of Physics, Chemistry, and Space Science among its top-cited fields. In fact, the Max Planck Society is the top-ranking institution overall in Physics and Space Science, and ranks at #2 overall in Chemistry."
>top-ranking institution overall in Physics and Space Science
>above mit, stanford and all the ivies
*9th symphony intensifies*
Because they worked on this project for 20 years and when they completed their testing the MPS released a media statement for a test run in a few weeks. If it works then this will be the DEMO reactor for the ITER project.
You know what, it's actually good. Like it or not pop-sci this is the best way to gather public interest and funding to advance science. For too long scientists have been too autistic to carry out decent PR campaigns hence we have retards saying "why build particle accelerators when there are starving kids in Africa?"
I know, I'm not complaining, the value of popularizing science is well known.